Open-emitter output with slew rate control
Quiescent current < 50mA
Bus voltage range -16 V .. +30 V
ISO 9141 and OBDII compliant
Wide temperature range -40 .. 125 C
SOIC14 and SOIC8 package
Baudrate 9600
Automotive applications
Part No.
Temperature Suffix
Package code
TH3044.2A
K ( -40C to +125C )
DC-14 ( SOIC14, 150mil )
TH3044
K ( -40C to +125C )
DC-8 ( SOIC8 , 150mil)
The TH3044 is a bidirectional bus interface
device for data transfer from 5V to 12V
supply.For proper functionality control units
are implemented.
This interface device was especially designed
for automotive applications.
Pin Diagram
SOIC14NB
TH3044
1
VCC
GND
RXD
NRXD
BUS
VBAT
SEN/STA
TxD
14
13
12
11
10
9
8
7
6
5
4
2
3
TH3044
1
VCC
GND
RXD
N.C.
BUS
VBAT
SEN/STA
TxD
8
7
6
5
4
2
3
SOIC 8
Nov/02
Page 1
3901003044
Rev. 003
TH3044
K-Bus Interface
TH3044
K-Bus Interface
Nov/02
Page 2
3901003044
Rev. 003
All voltages are referenced to ground (GND). Positive
currents flow into the IC. The absolute maximum ratings
(in accordance with IEC 134) given in the table below are
limiting values that do not lead to a permanent damage
of the device but exceeding any of these limits may do
Absolute maximum ratings
so. Long term exposure to limiting values may affect the
reliability of the device. Reliable operation of the TH3044
is only specified within the limits shown in "Operating
conditions"
Operating Conditions
Parameter
Symbol
Min
Typ
Max
Unit
Battery Voltage
V
BAT
6
16
V
Supply Voltage
V
CC
4.5
5.5
V
Operating Temperature
T
A
-40
125
C
Parameter
Symbol
Condition
Min
Max
Unit
Battery Voltage
V
BAT
-0.3
30
V
T
500 ms
40
Battery Current
I
BAT
20
mA
Supply Voltage
V
CC
7
V
Supply Current
I
CC
10
mA
Input Voltage SEN/STA,TxD
V
IN
-0.3
VCC+0.3
V
Input Current SEN/STA, TxD
I
IN
-10
10
mA
Input Voltage BUS
V
INBUS
-16
30
V
T
500 ms
40
Output Current RxD, NRxD
I
OUT
-10
10
mA
Operating Temperature
T
A
-40
125
C
TH3044
K-Bus Interface
Nov/02
Page 3
3901003044
Rev. 003
Static Characteristics
V
DD
= 4.5 to 5.5V, V
Bat
= 6 to 16V, T
amb
= -40C to +125C,
unless otherwise specified
Parameter
Symbol Condition
Min
Typ
Max
Unit
Supply
Power-on-reset Threshold VCC
V
CCPOR
3.0
4.0
V
Power-on-reset Threshold VBAT
V
BATPOR
3.0
4.5
V
Quiescent Current, ICC + IBAT
I
CCBAT
VCC = 5V, VBAT = 12V,
BUS, TxD, SEN/STA, RxD
and NRxD open
50
A
TxD, SEN/STA, RxD, NRxD
Pull-up Current TxD
I
pu
-330
-250
-170
A
Pull-down Current SEN/STA
I
pdSEN
170
250
330
A
Pull-up Current SEN/STA
I
puSEN
-330
-250
-170
A
Input Voltage Low TxD, SEN/STA
V
IL
0.25
V
CC
Input Voltage High TxD, SEN/STA
V
IH
0.75
V
CC
Output Voltage Low RxD, NRxD
V
OL
I
OUT
= 1 mA
1
V
Output Voltage High RxD, NRxD
V
OH
I
OUT
= 1 mA
V
CC
-1.0
V
BUS
Input Voltage Low BUS
V
IL
0.45
V
BAT
Input Voltage High BUS
V
IH
0.55
V
BAT
Hysteresis Input Voltage
V
HYS
50
mV
Input Resistance BUS
R
IN
V
BAT
= 0..40V
400
600
1500
k
V
BAT
= 0..40V, T
A
= 85C
1300
k
V
BUS
= 12V
60
k
Output Voltage BUS
V
BUS
VBAT = 12V,
SEN/STA = Low,
I
BUS
= 40mA
1.2
V
I
BUS
= 25mA
1.0
V
Output Sinking Current BUS (current
limiting)
I
LIM
V
BUS
> 3.5V
40
110
mA
Output Sinking Current BUS (before fold
back)
I
BUS
180
mA
TH3044
K-Bus Interface
Nov/02
Page 4
3901003044
Rev. 003
Dynamic Characteristics
Parameter
Symbol Condition
Min
Typ
Max
Unit
Propagation Delay TxD -> RxD, NRxD
t
pd
20
s
Threshold Voltage Fold-Back
V
FB
3.0
V
Slew Rate BUS
dV/dTfall
-2.2
-1.6
-1.0
V/
s
dV/dTrise
1.0
1.6
2.2
V/
s
Symmetry of Slew Rate BUS
dV/dTsym
0.3
V/
s
Debouncing Time BUS
t
debH
t
debL
High or Low Pulse
1.5
2.8
4.0
s
Symmetry of Debouncing Time BUS
t
debsym
0.5
s
Bit-Compare Time BUS, SEN/STA, TxD
t
bc
35
52
70
s
Recover Time BUS, TxD
t
rec
30
50
75
s
Enable Time for transmit path BUS, TxD
t
ena
0.92
1.33
1.8
ms
Constant-Low Time BUS, TxD
t
low
3
6
12
ms
TH3044
K-Bus Interface
Nov/02
Page 5
3901003044
Rev. 003
Figure 1 - Block Diagram
POR
VBAT
POR
VCC
Control-
logic
Bit-Compare
Constant-Low
VCC
ESD
ESD
VCC
OSC
Vref
Biasing
t
DEB
pnp-
Control
- slew rate
- I
B
- foldback
V
thH
V
thL
RxD
NRxD
TxD
SEN/STA
BUS
The TH3044 is used as a K-Bus interface. It
builds the connection between the serial 5V
bus line and the 12 V bus line. To avoid losses
of data informations control functions are
implemented.
Transmit
During the transmission the data at the pin
TxD will be transferred to the pin RxD (NRxD)
as well as to the pin BUS.
SEN/STA
TxD
BUS
To minimise the electromagnetic emission of
the bus line, the slew rate of the rising and
falling edges of the data signals are limited.
Receive
The receiving path is always transparent.
Independent of the mode the pin RxD and
NRxD (inverted) are related to signal at the pin
BUS. Voltage spikes on the bus signal are
sup-pressed by the implemented debouncing
circuit.
BUS
RxD
t
debH
t
debL
< t
debH
< t
debL
TH3044
K-Bus Interface
Nov/02
Page 6
3901003044
Rev. 003
Bit Compare
Are the signals at the pin TxD and the pin BUS
within a specified time t
bc
not identical, the
transmission will be interrupted.
If both signals at TxD and BUS are "High"
within the time t
ena
the transmission will be
enabled. To switch the TH3044 into the
receive mode a low level "0" has to be applied
to the pin Bus. If the TH3044 is part of a
complex bus system the first device which
transmits a low level "0" to the bus line forces
all other TH3044 to switch into the receive
mode. This state is valid until t
ena
.
The bitcompare-function is frequently retrig-
gered by every new bit-comparison of two
different levels.
The bit-compare-function is activ when the pin
SEN/STA is open (not overwritten).
TxD
BUS
t
ena
t < t
bc
SEN/STA
t
ena
t
bc
Constant Low
A falling edge at pin TxD (from "1" to "0") starts
the internal constant low timer.
If the low level "0" is valid for the time t low the
transmission unit of the TH3044 will be
disabled.
The receive unit is still active. A high level "1"
at TxD with a minimum pulse width of t resets
the constant low timer.
TxD
SEN/STA
t
low
t
ena
t < t
rec
SEN/STA
The pin SEN/STA is bidirectional. Used as an
output the pin indicates whether the transmit-
path is enabled or disabled:
SEN/STA ="0"
transmission path is enabled
SEN/STA ="1"
transmission path is disabled
Using this pin as an input the transmission
path can be overwritten (independent of bit-
compare and constant-low function):
SEN/STA="0"
forcing the transmission path free
SEN/STA="1"
disable the transmission path
Undervoltage
Undervoltage at pin VBAT or pin VCC doesn't
occur an unwanted low level at pin Bus (see
chapter "Transmit")
TH3044
K-Bus Interface
Nov/02
Page 7
3901003044
Rev. 003
Connecting Supply Pin's
Connecting VBAT, VCC and GND in random
sequence does not cause damaging of the
device. The absence of VBAT-, VCC- or GND-
connection either alone or in any combination
does not influence or disturb the bus.
Reset
The pin BUS remains in tri-state, until internal
RESET state is released.
Reverse Protection
To protect the TH3044 from reverse voltages,
evers protection diode needs to be connected
to pin VBAT.
EMC Filter
In order to minimise EMC radiation a LC filter
(33 uH, 82 pF) is recommended. As an option
a RC filter (10
, 100 pF) can be also used.
SEN/STA
TxD
RxD
NRxD
VBAT
BUS
VCC
GND
TH3044
MCU
TH3044
TH3044
TH3044
TH3044
V
Bat
V
Bat
10
100p
optinal
RC-EMC Filter
EMC Filter
33uH
82p
BUS pullups
R
pu
> 350
100n
2.2u
100n
100p...220p
optinal
for improving ESD
Performance
TH3044
K-Bus Interface
Nov/02
Page 8
3901003044
Rev. 003
Pin SOIC14 Pin SOIC 8
Name
I/O
Function
3
1
GND
P
Ground
4
2
VCC
I
Supply Voltage 5V
6
3
BUS
I/O
K-Bus
7
4
VBAT
P
Battery Voltage
10
5
SEN/STA
I/O
Transmit Status
11
6
TXD
I
Transmit Input
13
7
RXD
O
Receive Output
14
NRXD
O
Inverted Receive Output
TH3044
1
VCC
GND
RXD
NRXD
BUS
VBAT
SEN/STA
TxD
14
13
12
11
10
9
8
7
6
5
4
2
3
TH3044
1
VCC
GND
RXD
N.C.
BUS
VBAT
SEN/STA
TxD
8
7
6
5
4
2
3
SOIC 14 NB
SOIC 8
TH3044
K-Bus Interface
Nov/02
Page 9
3901003044
Rev. 003
DC ( SOIC14NB) Package Dimensions
1 2 3
D
E
H
b
e
A1
A
L
Small Outline Integrated Circiut (SOIC),
All Dimension in mm, coplanarity < 0.1 mm
D
E
H
A
A1
e
b
L
SOIC 14
150 mil
min
max
8.55
8.75
3.80
4.00
5.80
6.20
1.35
1.75
0.10
0.25
1.27
0.33
0.51
0.40
1.27
0
8
All Dimension in inch, coplanarity < 0.004"
SOIC 14
150 mil
min
max
0.337
0.334
0.150
0.157
0.228
0.224
0.053
0.069
0.004
0.010
0.050
0.013
0.020
0.016
0.050
0
8
TH3044
K-Bus Interface
Nov/02
Page 10
3901003044
Rev. 003
SOIC8 Package Dimensions
Small Outline Integrated Circiut (SOIC),
DC
(
SOIC 8, 150 mil)
All Dimension in mm, coplanarity < 0.1 mm
D
E
H
A
A1
e
b
L
min
max
4.8
5.00
3.80
4.00
5.80
6.20
1.35
1.75
0.10
0.25
1.27
0.33
0.51
0.40
1.27
0
8
All Dimension in inch, coplanarity < 0.004"
min
max
0.189
0.197
0.150
0.157
0.228
0.244
0.053
0.069
0.004
0.010
0.050
0.013
0.020
0.016
0.050
0
8
TH3044
K-Bus Interface
Nov/02
Page 11
3901003044
Rev. 003
!
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/
Electronic semiconductor products are sensitive to Electro Static Discharge (ESD).
Always observe Electro Static Discharge control procedures whenever handling semiconductor
products.
TH3044
K-Bus Interface
Nov/02
Page 12
3901003044
Rev. 003
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
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