MLX902xx Name of Sensor

Rev Y.X

22/Aug/98

Page 1

MLX90719

General purpose timer

3901090719

Page 1

Aug/02

Rev. 002

Features and Benefits

m CMOS technology

MLX8 core with 8 accumulators, 80 bytes RAM and 6K ROM
1 high voltage input (detection of mains-active)
Zero-crossing detection input to detect the 50/60Hz
7 standard inputs of which 2 can be used as comparator inputs and 2 can be configured

as open-collector outputs.

15 configurable LCD outputs (segment/backplane)
3 relay drivers which can also be used to drive a triac or LED's without the need for ex-

ternal resistors.

Buzzer driver with programmable frequency
On-chip 4MHz oscillator, crystal oscillator and low power RC oscillator
Low power mode (battery or decoupling capacitor)
High supply voltage eliminates the need for high power resistors
Battery backup
On-chip watchdog

Applications

24 hour timer for cooker applications, coffee maker, ...

Ordering Information

Part No.

Temperature Suffix

Package Code

Option Code

MLX90719

C ( 0°C to 70°C )

DF (SOIC 16, 300mil) -x

The customer specific version code (defining the ROM content) is indicated with 1 character at the end of the
ordering number.

Description

The ASIC consists of a dedicated microcontroller
combined with on-chip analog and digital blocks,
which can be configured to a great extend. This
makes it ideal to adapt it to different applications by
means of an update in the software. The number of
external components for the electronic module is
minimized. A typical application mainly consists of
the MLX90719 ASIC, a number of command buttons,
a LCD, a relay, some LED's and a buzzer.
The number of buttons and their function can be
freely chosen. The configuration of the LCD, the
number of backplanes and its pinout is also under
software control. Three outputs are available for a
relay and LED's.

Functional Diagram

MLX90719

LX11

Interrupt

controller

RAM

1 x comp

Counter

W atchdog

XT1

XT2

IN 1-8

ZCD

VDD4

BAT
VSS

LCD 1-15

OUT A,B,C

BUZ

17bit timer

Controller

125kHz

oscillator

4MHz

PLL

oscillator

POR

8 x input

Vreg

Xtal

LCD

Output

A, B, C

Buzzer

Zero

cross

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General purpose timer

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Rev. 002

General description

The MLX90719 is an ASIC which is ideally suited
for timing control application, low cost as well as
high end, such as clocks in coffee machines, cook-
ers, baking equipment,...

The ASIC consists of a dedicated microcontroller
combined with on-chip analog and digital blocks,
which can be configured to a great extend. This
makes it ideal to adapt it to different applications by
means of an update in the software. The number of
external components for the electronic module is
minimized. A typical application mainly consists of
the MLX90719 ASIC, a number of command but-
tons, a LCD, a relay, some LED's and a buzzer.
The number of buttons and their function can be
freely chosen. The configuration of the LCD, the
number of backplanes and its pinout is also under
software control. Three outputs are available for a
relay and LED's.

Main functions:

General-purpose timer chip based on the 8-bit
LX11 core, including 80 bytes RAM and 6 Kbytes
ROM.
Programming of the ROM and selection of all other
options is done with one mask.
An interrupt controller guarantees exact timings
and a clean refresh rate of the LCD.
High supply voltage eliminates the need for high
power resistors.
6 digital inputs and 2 I/O pins (function is under
software control).
1 comparator (uses 2 of the digital inputs) which
can be used for analog measurements.
3 high current output drivers. They are suitable for
driving low cost 12V relays, but other types can
also be used. They can also be used to drive triac
or LED's without the need for external resistors.
1 buzzer output for piezo electric buzzers, with
programmable frequency.
The LCD interface consists of 15 outputs, each of
them can be configured as backplane or segment
driver.
The time base for the clock function is derived ei-
ther from the mains frequency or from a crystal
oscillator.
The clock frequency for the microcontroller, relay
drivers and buzzer output is derived from an on
chip oscillator, which is calibrated under software
control.
For applications that are disconnected from the
mains for longer times, a battery backup can be
foreseen, so that the module always keeps track of
the time.

For short mains interruptions (up to 5 minutes), the
energy in a decoupling capacitor can be used to
keep track of the time.
An on-chip watchdog ensures the functioning of the
chip under all environmental conditions.
The package size can be adapted to the number of
used pins (non-used I/O's do not need to be
bonded).

MLX902xx Name of Sensor

Rev Y.X

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MLX90719

General purpose timer

3901090719

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Rev. 002

MLX90719 Electrical Specifications

Parameter

Symbol Test Conditions

Min Typ Max Units

Ambient temperature

Tamb

°C

Maximum chip temperature Tic

150 °C

Maximum allowed source

supply current

Idd4m

Drivers off = all the current flows in the chip

Analog features

Power supply

The MLX90719 supply pin (VDD4) must be connected
by external series resistor and rectifier diode to the
mains. An internal Zener function limits the voltage at
VDD4 to 70-80V. For proper operation, a decoupling
capacitor needs to be connected between VDD4 and
VSS (see figure 1).

90719

Vdd4

Vss

line

6k*

22uF*

*for information only

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General purpose timer

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Rev. 002

The MLX90719 has several internal supply lines for both analog and digital blocks:

Parameter

Symbol Test Conditions

Min Typ Max Units

Voltage applied at the supply pin

Vdd4

Idd4 = 5mA

DRAINB = Vss

Internal buzzer driver supply

Vbuz

Option OBZ3 active

Internal 11V supply

Vdd2

Internal 5V for main oscillator

Vdd1

4.5

5.0

5.5

Internal 5V for digital

Vdd

Normal mode

4.0

5.0

6.0

Low power mode

2.7

LCD driver supply

Vlcd

Option OLCD1 active

3.0

Option OLCD2 active

3.25

Option OLCD3 active

3.5

Option OLCD4 active

3.75

Option OLCD5 active

Option OLCD6 active

4.25

Option OLCD7 active

4.5

Option OLCD8 active

4.75

Option OLCD9 active

Option OLCD10 active

5.25

Option OLCD11 active

5.5

Option OLCD12 active

5.75

Option OLCD13 active

Option OLCD14 active

6.25

1Vlcd/3

Vlcd1

Of Vlcd

2Vlcd/3

Vlcd2

Of Vlcd

Idd4

For Vdd4<Vaporl (LPM)

For Vdd4 = 73V

Voltage of backup battery

Vbat

2.7

3.3

Supply for external circuitry

Vext

At Iext = 2mA

3.9

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General purpose timer

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Rev. 002

Parameter

Symbol Test Conditions

Min Typ Max Units

High level threshold

Vdporh

3.4

Low level threshold

Vdporl

2.2

2.6

Hysteresis

Vdphyst

0.3

Notes:
The power on reset does not reset the system when entering low power mode with battery (Vdporl<Vbat).
The power on reset resets the system if the RAM data may be corrupt due to undervoltage (Vdporl>RAM data
retention voltage).

Analog Power-On Reset

The MLX90719 includes a high voltage power-on reset that watches on VDD3.
This block has two outputs APORL and APORH:
APORL = 1 when VDD3 > Vaporl
APORH = 1 when VDD3 > Vaporh (see table 4)
The states of APORH and APORL define the operation mode of the chip (see sections "Sleep manager" and
"Interrupt controller").

In low power mode the analog power on reset operates in strobe mode. It is only enabled a few microseconds at
each rising edge of the signal ASTR generated by the digital core.
When Vdd3 > Vaporl the circuit goes out of strobe mode.

Parameter

Symbol Test Conditions

Min Typ Max Units

High level threshold

Vaporh

Low level threshold

Vaporl

Hysteresis

Vaphyst

Strobe frequency

Fastr

Slow rate of Vdd3>200V/s

Low power mode (LPM)

In low power mode (when the mains have been disconnected from the application) all supply lines are disabled
except VDD, which is generated by a low consuming regulator. The current is taken from the external decoup-
ling capacitor of VDD4 or from a backup battery connected to pin BAT. This depends on the type of application
defined by the mask option OXBAT implemented within the chip:
OXBAT = 1 for application with battery and crystal.
OXBAT = 0 for applications without battery or crystal.

LCD operating voltage

The LCD operating voltage can have14 different values and can be chosen by mask options.

Supply for external components

If the mask option OVEXT is set the MLX90719 can supply some external circuitry from the internal Vdd1
through pin IN5B (which can not be used as input anymore).

Power On Reset

This module ensures a correct start of the MLX90719 logic.
The reset signal (DPORB) rises when VDD>Vdporh and falls when VDD<Vdporl

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General purpose timer

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Zero crossing detector

The MLX90719 includes a zero crossing detector on pin ZCD. This detector contains two comparators with hys-
teresis. The first comparator has negative thresholds and the second one has positive thresholds (see table 5).
Outputs ZOUT1 and ZOUT2 of those comparators are changing as follows:
ZOUT1 rises when Vmains>Vz1h
ZOUT1 falls when Vmains<Vz1l
ZOUT2 rises when Vmains>Vz2h
ZOUT2 falls when Vmains<Vz2l

A mask option defines the levels of those thresholds. Low levels (+/- 5V, option OZCD = 0) are suitable for zero
crossing detection and high levels (+/- 20V, option OZCD = 1) for frequency detection with a better noise immu-
nity.
A 1M

resistor must be connected between pin ZCD and the mains.

Parameter

Symbol Test Conditions

Min Typ Max Units

High level threshold 1

Vz1h

Rzcd = 1Mohm

-5

Rzcd = 1Mohm, OZCD = 1

-5

Low level threshold 1

Vz1l

Rzcd = 1Mohm

-9

Rzcd = 1Mohm, OZCD = 1

-29

High level threshold 2

Vz2h

Rzcd = 1Mohm

Rzcd = 1Mohm, OZCD = 1

Low level threshold 2

Vz2l

Rzcd = 1Mohm

Rzcd = 1Mohm, OZCD = 1

External resistor

Rzcd

Vline = 230VAC typical

0.8

1.2

Mohm

Low voltage inputs

The MLX90719 has 7 CMOS Schmitt trigger inputs with internal pull-up.
Note: the input signals are inverted in the digital core so these inputs are active low.
Signal ENINB (active at 0) enables the pull-up current flowing through external pad to VSS if the input is pushed
to VSS. When ENINB=1 (input disabled), DINxB = 1.
The programmer must enable inputs by setting bit ENIN of P7 at least 5us before reading the input port P3 (see
section "I/O ports"). The debouncing of inputs must be done by software.

Parameter

Symbol Test Conditions

Min Typ Max Units

Pull-up current

Ipu1

Input to Vss

100 uA

Low level threshold

Vthinl

%Vdd

High level threshold

Vthinh

%Vdd

Hysteresis

Vhystin

%Vdd

Multipurpose inputs:
Inputs 3 and 6 can be used also as pull-down outputs: the pull down transistors are turned on by setting bits
PD3 and PD6 of P6 (see section "I/O ports").
Inputs 1, 2 and 4 are used by the on-chip comparator (see section "comparator")
Input 5 can be turned into supply for external circuitry by mask option OVEXT (see "Power supply").

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General purpose timer

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Rev. 002

High voltage input

The MLX90719 has an eighth input that can be used either as a standard input (as described above) or as an
high voltage input to detect the mains via an external resistor. The high voltage mode is enabled if mask option
OIN7 is set.
Output DIN7B of this detector is high when Vmains>Vthinh2 and low when Vmains<Vthinl2.

Note: signal DIN7B is inverted whitin the digital core.

Parameter

Symbol Test Conditions

Min

Typ

Max Units

Pull-down current

Ipd2

Low level threshold

Vthinl2

Rin = 1Mohm

6.9

High level threshold

Vthinh2 Rin = 1Mohm

12.3

External resistor

Rin

0.8

1.2

Mohm

Main oscillator

The MLX90719 contains a 4Mhz on-chip oscillator.
In low power mode this oscillator is turned off.

Parameter

Symbol Test Conditions

Min

Typ

Max Units

Master frequency of the

main oscillator (signal

CKM)

Fckm

Over full temp. and supply range

2.4

4.0

5.6

MHz

Low power crystal oscillator

In case of applications with battery and crystal (OXBAT = 1) the MLX90719 uses a low power crystal oscillator
as time reference for both normal and low power mode.
This oscillator requires a standard 32kHz crystal connected between pin XTAL1 and pin XTAL2.
No external capacitor is required for proper operation.

Parameter

Symbol Test Conditions

Min

Typ

Max Units

Master frequency of the

crystal oscillator

Fckx

Over full temp. and supply range

32768

Note: This oscillator is disabled if OXBAT = 0.

VDD

INxB

ENINB

DINxB

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General purpose timer

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Low power RC oscillator

In case of applications without battery or crystal (OXBAT = 0) the MLX90719 uses an on-chip low power RC os-
cillator to count time during a few minutes after the mains has been disconnected (low power mode).

Parameter

Symbol Test Conditions

Min Typ Max Units

Master frequency of the

low power RC oscillator

Fckl

Over full temp. and supply range

1.0

2.5

kHz

Notes:
As the CPU must calibrate it in normal mode, the low power oscillator is running continuously.
The low power RC oscillator is disabled if OXBAT = 1.

LCD outputs

The MLX90719 has 15 configurable LCD outputs able to drive either a backplane or a segment by mask option:
OLCDx = 0 => segment
OLCDx = 1 => backplane
The LCD voltages are defined according to bits LCDx and CKLCD written in P3 and P4 (see section "I/O
ports"). With Vcdl1 and Vlcd2 being respectively 1/3Vlcd and 2/3Vlcd, the MLX90719 is suitable for LCD having
1, 2, 3 or 4 backplanes.

Parameter

Symbol Test Conditions

Min Typ Max Units

Output impedance

Rolcd

All cases

kohm

OLCDx

LCDx

CKLCD

OUT

Vlcd1

Vlcd2

Vlcd

Vss

Vlcd2

Vlcd1

Vss

Vlcd

Relay drivers

The MLX90719 includes 3 pull-down power outputs A, B, and C able to drive relays, triacs or LED's.
The gates of the drivers are controlled respectively by signals POUTA, POUTB and POUTC generated by the
digital core (see section "PWM generator").
Each driver has its source and its drain connected to a pad (DRAINx and SOURCEx) except driver C of which
the source is connected to the ground. This allows a series connection of the drivers. In such a configuration
the current flowing through the relay is used to feed the LED's.

Internal current generator
In applications based on the following schematic, where the LED(`s) may have to be driven when the relay is
off, an internal current peak generator can be activated to supply the LED's through pin SourceA. This function
is enabled by bit INTCUR of P5 (see section "I/O ports"). When INTCUR is set the current generator is acti-
vated like a relay by signal PINT at frequency Fpwm and at 14.3% duty cycle (see "PWM generator").
Note: If the application has no relay, this feature allows the MLX90719 to drive 2 LED's without any external
resistors.

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General purpose timer

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Rev. 002

Parameter

Symbol Test Conditions

Min Typ Max Units

Ron of driver A

RonA

Source A pushed to VSS

Ron of driver B

RonB

Source B pushed to VSS

Ron of driver C

RonC

Voltage on pin DrainA

Vda

Voltage on pin DrainB

Vdb

Voltage on pin DrainC

Vdc

Voltage on pin SourceA

Vsa

Voltage on pin SourceB

Vsb

Rising edge duration, all

drivers

Load = 5k from VDD4 = 70V

Falling edge duration, all

drivers

Load = 5k from VDD4 = 70V

VDD4

90719

DrainA

SourceA

DrainB

SourceB

DrainC

RELAY

LED1

LED2

Current

gen.

PINT

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General purpose timer

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Buzzer driver

The MLX90719 includes a piezo buzzer driver.
The push-pull output stage of this driver operates at 15V. An internal resistor between the output pin and the
push-pull stage protects the chip against reverse piezo effect.

Parameter

Symbol Test Conditions

Min Typ Max Units

Output impedance

Rob

100 300 600 ohm

Maximum output frequency Fbuzm

kHz

Comparator

The MLX90719 includes a multi-purpose comparator.
Setting bit ECOMP of P3 (see section "I/O ports") enables this comparator. Inputs IN1B and IN2B become re-
spectively the positive and negative inputs of the comparator and IN4B becomes its output via a tri-state buffer.

To reduce the number of external components in applications using the comparator, a resistive bridge and a
feed back resistor (both internal) can be connected on the positive input of the comparator by mask option
OCOMP.

Notes:
Some logic in the digital core ensures that ENIN12B and ENIN4B = 1 when ECOMP = 1.
When ECOMP = 0 the comparator output is fixed to "1".

A programmable prescaler has been implemented to allow frequency measurement at the output of the com-
parator (line IN4B). The status of bits CM0 and CM1 of P3 define the prescale ratio as described in table 15:

electrical characteristics of the comparator.

Parameter

Symbol Test Conditions

Min Typ Max Units

Common mode range

Vcm

%Vdd

Offset

Vcoff

-30

CM1

CM0

Divide ratio

Prescaler bypassed

/16

/32

/64

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General purpose timer

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Digital features

I/O ports

The MLX90719 has 9 port addresses. Read and write instructions to the same address do not access to the
same port:

Note: * = reserved for test.

Out Description

Msb

Lsb

P0 Timer compare low

TCP7

TCP6

TCP5

TCP4 TCP3

TCP2

TCP1

TCP0

P1 Timer compare high

TCP15

TCP14 TCP13 TCP12 TCP11

TCP10

TCP9

TCP8

P2 Timer ctrl, comparator

CM1

CM0

ECOMP TRST COUNT EN24H

MUX1

MUX0

P3 LCD port

LCD8

LCD9

LCD10 LCD11 LCD12

LCD13

LCD14

LCD15

P4 LCD port

CKLCDB LCD1

LCD2

LCD3 LCD4

LCD5

LCD6

LCD7

P5 Power outputs

Not used INTCUR PC1

PC0

PB1

PB0

PA1

PA0

P6 PWM frequency adjust

PD6

PD3

DIV5

DIV4 DIV3

DIV2

DIV1

DIV0

P7 IT control, sleep, wdog

PWD

RSTWD FLAG

ENIN RFHIT

ETIMI

ECLKI

ESUPI

P8 Sound, test

CTST*

DTST*

MTST* LTST* SOUND3 SOUND2 SOUND1

SOUND0

Description

Msb

Lsb

P0 Timer low

P1 Timer high

T15

T14

T13

T12

T11

T10

P2 Timer msb, test

BATB*

T16

P3 Chip inputs

IN7

IN6

IN5

IN4

IN3

IN2

IN1

IN0

P4 Not used

P5 Not used

P6 Not used

P7 IT handler, flag

ZCD

FLAG

PTIMI

PCLKI

PSUPI

P8 Not used

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General purpose timer

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Sleep manager and watch dog

At power-on-reset the MLX90719 is in low power mode (PWD = 1).
When VDD3 reaches 65V (APORH = 1) PWD is reset and the main oscillator starts. To ensure a correct start of
the analog blocks, the CPU is kept in reset status for 2

main clock pulses (typically 8.2ms).

Once the microcontroller is working a watchdog circuitry will generate a system reset if the user program fails to
reset the watchdog counter. The watchdog delay is given by:

Twd = 57344 x 1/Fckm (= 14ms if Fckm = 4MHz)

The watchdog counter is reset each time a 1 is written on bit RSTWD of P7.

To distinguish a wake-up after power-on reset and a wake-up after low power mode, one can read the status of
bit FLAG (read/write bit in P7). This will be 0 after power on reset and 1 after low power mode if FLAG has been
set during normal mode.

The low power mode is set by bit PWD of P7. Since the main oscillator stops as soon as PWD = 1, setting bit
PWD must be the last instruction of the supply interrupt subroutine (see interrupt controller).

Debouncing
A debounce circuit eliminates positive spikes on line APORH to avoid unexpected wake-up due to distur-
bances. The debounce time (tdaporh) depends on OXBAT.
If OXBAT = 1 it derives from the crystal oscillator frequency and:
7.8ms < tdaporh < 11.7ms
If OXBAT = 0 it derives from the low power RC oscillator frequency and:
3.2ms < tdaporl < 24ms

Timer

The MLX90719 includes a 17-bit timer preceded by a 15-bit prescaler. The clock of the timer can be taken from
four different sources defined by the bits MUX0 and MUX1 of P2:

The battery and crystal option (OXBAT) defines which clock is connected to the prescaler input:
If OXBAT =1: the crystal oscillator output (CKX) drives the prescaler input
If OXBAT = 0: the low power RC oscillator output (CKL) drives the prescaler input.

Control bits (P2):
EN24H = 1 enables the 24h mode (see below).
COUNT = 1 enables the counter
TRST = 1 resets the counter and the prescaler.

Normal operation
In normal mode the timer is used as a free-running counter on CK125K. It can be read at any time without stop.
An interrupt is generated when the value of the timer reaches the value of the timer compare written in P1-P0.

Low power mode if crystal oscillator (OXBAT = 1)
In this mode the clock of the timer must be connected to the /2

output of the prescaler (1Hz).

Setting the 24h mode turns the timer into a modulo 86400 counter if a correct value has been written in P1-P0.
The timer being automatically reset when T16=1 and T[15:0] = TCP[15:0], this value must be 517Fh to give T
[16:0] = 86399.

MUX1

MUX0

Timer clock source

Description

CK125K

Main clock divided by 32 (typically 125kHz)

D2P15

prescale output

D2P9

prescale output

D2P3

prescale output

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General purpose timer

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At wake-up the value of the timer is the number of seconds passed since the beginning of sleep. An arbitrary
time of 0.5s should be added to this number to compensate the error of 0/- 1s due to the timer resolution.

Low power mode without crystal oscillator (OXBAT = 0)
In this mode the timer clock must be connected to the /2

output of the prescaler (about 5Hz).

At wake up a calibration of the low power oscillator can be done by connecting the timer clock to the /2

output

of the prescaler and counting during 250ms (given by 25 half period of the mains at 50Hz and 30 half period at
60Hz).
Those prescale ratios allow a calibration of the low power oscillator with only one 16-bit division if its frequency
is in the range of 1-5kHz and if the maximum time to count is 5min.

Interrupt controller

The MLX8 core accepts only one interrupt source.
The MLX90719 has 3 interrupt sources:

Supply

Clock reference (crystal oscillator or zero crossing detector)

Timer

These three hardware parts will interrupt the MLX8 core to address 21h (interrupt address).
In order to recognize the interrupting device, an interrupt handler is readable at port P7 (bits PSUPI, PCLKI and
PTIMI). In case of interrupt:

PSUPI is set if the voltage on VDD3 has decreased under 50V (APORL=0)

PCLKI is set if a clock reference pulse has occurred.

PTIMI is set if the timer has reached the timer compare value (16-bit word in P0-P1).

Main program

Read P7

PSUPI=1

PCLKI=1

PTIMI=1

Interrupt subroutine
....
Clear IT:
set & reset ECLKI

Interrupt subroutine
....

SLEEP

Interrupt subroutine
....
Clear IT:
set & reset ETIMI

Refresh IT controller :
set & reset RFHIT

At address 21h :

interrupt processing

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Option OXBAT defines which source generates the clock reference interrupt:
If OXBAT = 1 the clock interrupts are generated at the rate of 128Hz (Crystal frequency divided by 256).
If OXBAT = 0 the clock interrupts are generated at the rate of twice the mains frequency by the zero crossing
detector (combination of signals ZOUT1 and ZOUT2) that is 100Hz or 120Hz.

The main purpose of the timer interrupt is to rate the multiplexing of the LCD but it can be used to control a
triac.

Each interrupt can be enabled/disabled and cleared by setting or resetting ESUPI, ECLKI and ETIMI in P7.
As several interrupts may occur at the same time a fourth control bit RFHIT (of P7) has been implemented to
refresh the interrupt controller after each interrupt subroutine. The flow chart shows the interrupt process:
Debouncing
A debounce circuit eliminates negative spikes on line APORL to avoid unexpected supply interrupts due to dis-
turbances. The debounce time (tdaporl) depends on OXBAT.
If OXBAT = 1 it derives from the crystal oscillator frequency and:
7.8ms < tdaporl < 11.7ms
If OXBAT = 0 it derives from the low power RC oscillator frequency and:
3.2ms < tdaporl < 24ms

Both outputs of the zero crossing detector are combined in a debounce circuit that generates a periodic signal
rising at each zero crossing of the mains without delay. This signal (ZCD) is connected to the interrupt handler
(if OXBAT = 0) at bit PCLKI. The debounce period is typically 2ms but can vary from 0.6ms to 6ms because is it
generated from the low power RC oscillator.

Zero crossing signal on P7
The zero crossing signal is readable at bit ZCD of P7. This feature may be used to detect zero crossing in crys-
tal-based applications.

PWM generator

The three relay drivers of the MLX90719 can be driven independently at 0%, 14.3%, 28.6% and 100% duty
cycle (except driver A which can not be driven at 100% duty).
Bits PA0 to PC1 of P5 set the duty cycle of each driver (signals POUTA, POUTB and POUTC) and bit INTCUR
activates the current peak generator (signal PINT):

Note: * = 0% for driver A

t30 is given by: tclki < t30 < 2tclki
where tclki is the delay between two clock interrupts:

tclki = 10ms if zero crossing detector is used and Fmains = 50Hz

tclki = 8.33ms if zero crossing detector is used and Fmains = 60Hz

tclki = 7.81ms if crystal oscillator is used

In all cases: 7.81ms < t30 < 15ms

INTCUR

Px1

Px0

Duty cycle of

0 %

14.3 %

100 % *

28.6 % for t30 then

14.3%

0 %

14.3%

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The PWM frequency is programmable. It depends on the main oscillator frequency and on the 6-bit divide ratio
written in P6:
Fpwm = Fckm /(7 x DIV[6:0]) (= 22kHz for Fckm = 4MHz and DIV[6:0] = 26)

As Fckm can vary, the divide ratio must be calculated periodically by software to reference Fpwm to the crystal
frequency or to the mains frequency.

Sound generator

The MLX90719 includes a sound generator able to produce more than 8 tonalities.
The output frequency Fbuz is defined by bits SOUND3 to SOUND0 of P3:
Fbuz = (7 x Fpwm) / (8 x S) (see table 21)

Mask options

The following table lists all options of the MLX90719 chip:

SOUND3

SOUND2

SOUND1

SOUND0

Fbuz if Fpwm = 22kHz

Off

(9.62kHz)

6.42kHz

4.81kHz

3.85kHz

3.21kHz

2.75kHz

2.41kHz

2.14kHz

1.93kHz

(1.75kHz)

(1.60kHz)

(1.48kHz)

(1.38kHz)

(1.28kHz)

(1.20kHz)

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Name

Value = 0

Value = 1

Bit*

OXBAT

No battery, no crystal

Battery + crystal

OVLCD1

Vlcd = 3V

OVLCD2

Vlcd = 3.25V

OVLCD3

Vlcd = 3.5V

OVLCD4

Vlcd = 3.75V

OVLCD5

Vlcd = 4V

OVLCD6

Vlcd = 4.25V

OVLCD7

Vlcd = 4.5V

OVLCD8

Vlcd = 4.75V

OVLCD9

Vlcd = 5V

OVLCD10

Vlcd = 5.25V

OVLCD11

Vlcd = 5.5V

OVLCD12

Vlcd = 5.75V

OVLCD13

Vlcd = 6V

OVLCD14

Vlcd = 6.25V

OVEXT

No external 5V supply

External 5V supply on IN5B

OZCD

Low thresholds

High thresholds

OIN7

Low voltage

High voltage

OCOMP

Bridge + feedback disabled

Bridge + feedback enabled

OLCD1

LCD1 = segment

LCD1 = backplane

OLCD2

LCD2 = segment

LCD2 = backplane

OLCD3

LCD3 = segment

LCD3 = backplane

OLCD4

LCD4 = segment

LCD4 = backplane

OLCD5

LCD5 = segment

LCD5 = backplane

OLCD6

LCD6 = segment

LCD6 = backplane

OLCD7

LCD7 = segment

LCD7 = backplane

OLCD8

LCD8 = segment

LCD8 = backplane

OLCD9

LCD9 = segment

LCD9 = backplane

OLCD10

LCD10 = segment

LCD10 = backplane

OLCD11

LCD11 = segment

LCD11 = backplane

OLCD12

LCD12 = segment

LCD12 = backplane

OLCD13

LCD13 = segment

LCD13 = backplane

OLCD14

LCD14 = segment

LCD14 = backplane

OLCD15

LCD15 = segment

LCD15 = backplane

* Only applicable for the development version of the MLX90719

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Name

Num. (CCW)

Description

Options

LCD15

LCD14

LCD13

LCD12

LCD11

LCD10

LCD9

LCD8

LCD7

LCD6

LCD5

LCD4

LCD3

LCD2

LCD1

XTAL1

XTAL2

BAT

Battery pin

IN0B

Input 0

IN1B

Input 1

Comparator "+"

IN2B

Input 2

Comparator "-"

IN3B

Input 3

BUZ

Buzzer output

VSS

Vss

DRAINC

Drain of driver C

SOURCEB

Source of driver B

DRAINB

Drain of driver B

Pinout

Package type: SSOP36

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Development board

Melexis has available a development kit which contains a evaluation circuit board, a ROM emulator, interface
cables, all necessary software and a sample of the MLX90917 (development version). The evaluation board is
a standard version that can be customized to an extended range of applications. The standard version includes
a buzzer, a LCD, a relay and some breadboard space to build up the customized application. (push buttons,
high-power outputs, temperature measurement, ...) The available software consists of assembler, linker, simu-
lator and the interface software for the ROM emulator. By using this emulator the user is able to see and modify
all internal registers and the RAM contents. On a break event, the user program is replaced by a shadow moni-
tor, which exchanges data with the host.

For software development a special version of the MLX90917 is available. This version differs from the stan-
dard MLX90917 in two ways. It has a second ring of pads around the normal chip. In this way the chip can be
used with external memory, which makes it also possible to use the ROM emulator. With the development ver-
sion it is also possible to program the different `mask' options. The state of the different options should be writ-
ten by the programmer in specific ROM bytes. During the initialization phase of the chip, a dedicated part in the
software reads this bytes and writes the contents in specific memory elements, defining in this way the chosen
options.

More information about the development board and software can be found in the specific documentation de-
scribing the MLX90719 Development Kit.

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Reliability Information

Melexis devices are classified and qualified regarding suitability for infrared, vapor phase and
wave soldering with usual (63/37 SnPb-) solder (melting point at 183degC).
The following test methods are applied:

IPC/JEDEC J-STD-020A (issue April 1999)
Moisture/Reflow Sensitivity Classification For Nonhermetic Solid State Surface Mount Devices
CECC00802 (issue 1994)
Standard Method For The Specification of Surface Mounting Components (SMDs) of Assessed
Quality
MIL 883 Method 2003 / JEDEC-STD-22 Test Method B102
Solderability

For all soldering technologies deviating from above mentioned standard conditions (regarding
peak temperature, temperature gradient, temperature profile etc) additional classification and
qualification tests have to be agreed upon with Melexis.

The application of Wave Soldering for SMD's is allowed only after consulting Melexis regarding
assurance of adhesive strength between device and board.

For more information on manufacturability/solderability see quality page at our website:

http://www.melexis.com/

ESD Precautions

Electronic semiconductor products are sensitive to Electro Static Discharge (ESD).
Always observe Electro Static Discharge control procedures whenever handling semiconductor
products.

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Disclaimer

Devices sold by Melexis are covered by the warranty and patent indemnification provisions appear-
ing in its Term of Sale. Melexis makes no warranty, express, statutory, implied, or by description re-
garding the information set forth herein or regarding the freedom of the described devices from pat-
ent infringement. Melexis reserves the right to change specifications and prices at any time and with-
out notice. Therefore, prior to designing this product into a system, it is necessary to check with
Melexis for current information. This product is intended for use in normal commercial applications.
Applications requiring extended temperature range, unusual environmental requirements, or high
reliability applications, such as military, medical life-support or life-sustaining equipment are specifi-
cally not recommended without additional processing by Melexis for each application.
The information furnished by Melexis is believed to be correct and accurate. However, Melexis shall
not be liable to recipient or any third party for any damages, including but not limited to personal in-
jury, property damage, loss of profits, loss of use, interrupt of business or indirect, special incidental
or consequential damages, of any kind, in connection with or arising out of the furnishing, perform-
ance or use of the technical data herein. No obligation or liability to recipient or any third party shall
arise or flow out of Melexis' rendering of technical or other services.
© 2002 Melexis NV. All rights reserved.

For the latest version of this document, go to our website at:

www.melexis.com

Or for additional information contact Melexis Direct:

Europe and Japan:

All other locations:

Phone: +32 13 67 04 95

Phone: +1 603 223 2362

E-mail: sales_europe@melexis.com

E-mail: sales_usa@melexis.com

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