Replacement of
TL494
MIK494
Pulse-Width-Modulation
Controller
September 1995 - revised September 2002
Description
The MIK494 incorporate on a single monolithic chip all the functions required in the construction of a pulse-width-modulation control
circuit. Designed primarily for power supply control, these devices offer the systems engineer the flexibility to tailor the power supply
control circuitry to his application.
The MIK494 contains an error amplifier, an on-chip adjustable oscillator, a dead-time control comparator, pulse-steering control flip-flop,
a 5-volt, 5% precision regulator, and output-control circuits. The error amplifier exhibits a common-mode voltage range from -0.3 volts to
V
CC
-2 volts. The dead-time control comparator has a fixed offset that provides approximately 5% dead time when externally altered. The
on-chip oscillator may be bypassed by terminating R
T
(pin 6) to the reference output and providing a sawtooth input to C
T
(pin 5), or it
may be used to drive the common circuits in synchronous multiple-rail power supplies. The uncommited output transistors provide either
common-emitter or emitter-follower output capability. Each device provides for push-pull or single-ended output operation, which may be
selected through the output-control function. The architecture of these devices prohibits the possibility of either output being pulsed
twice during push-pull operation.
Features
Complete PWM Power Control Circuitry
Uncommitted Outputs for 200 mA Sink or Source Current
Output Control Selects Single-Ended or Push-Pull
Operation
Internal Circuitry Prohibits Double Pulse at Either Output
Variable Dead-Time Provides Control over Total Range
Internal Regulator Provides a Stable 5-V Reference
Supply, 5%
Circuit Architecture Allows Easy Synchronization
MIK494
(top view)
Absolute Maximum Ratings
over operating free-air temperature range (unless otherwise noted)
Parameter Maximum
Units
Supply voltage, V
CC
41
Amplifier input voltage
V
CC
+0.3
Collector output voltage
41
V
Collector output current
250 mA
Operating free-air temperature range
0 to 70
Storage temperature range
-65 to 150
Lead temperature 1,6 mm from case for 10 seconds
260
C
Recommended Operating Conditions
MIK494
Parameter
Min Max
Units
Supply voltage, V
CC
7 40
Amplifier input voltage, Vi
-0.3 V
CC
-2
Collector output voltage, V
O
40
V
Collector output current (each transistor)
200
Current into feedback terminal
0.3
mA
Timing capacitor, C
T
0.47 10000 nF
Timing resistor, R
T
1.8 500 k
Oscillator frequency
1 300
kHz
Operating free-air temperature, T
A
0
70
C
Page 1 of 5
Replacement of
TL494
MIK494
Pulse-Width-Modulation
Controller
September 1995 - revised September 2002
Functional Block Diagram
Parameter Measurement Information
Page 2 of 5
Replacement of
TL494
MIK494
Pulse-Width-Modulation
Controller
September 1995 - revised September 2002
0%
MAX
0%
THRESHOLD VOLTAGE
THRESHOLD VOLTAGE
0 V
0.7 V
FEEDBACK
DUTY
CIRCLE
DEAD-TIME
CONTROL
INPUT
VOLTAGE
AT C
VOLTAGE
AT C1
VOLTAGE
AT C2
T
VOLTAGE WAVEFORMS
0
0
V
CC
V
CC
Figure 1. Operational test circuit and waveforms
+
+
-
-
AMPLIFIER
UNDER TEST
FEEDBACK
TERMINAL
OTHER
AMPLIFIER
V
ref
V
I
Figure 2. Amplifier characteristics
10%
10%
90%
90%
OUTPUT VOLTAGE WAVEFORM
tr
t f
(EACH OUTPUT
CIRCUIT)
TEST CIRCUIT
68
2W
15 V
OUTPUT
C = 15pF
(Includes probe and
jig capacitance)
L
Figure 3. Common-emitter configuration
10%
10%
90%
90%
tr
t f
(EACH OUTPUT
CIRCUIT)
TEST CIRUIT
OUTPUT VOLTAGE WAVEFORM
68
2W
15 V
OUTPUT
C = 15pF
(Includes probe and
jig capacitance)
L
Figure 4. Emitter-follower configuration
Page 3 of 5
Replacement of
TL494
MIK494
Pulse-Width-Modulation
Controller
September 1995 - revised September 2002
Electrical Characteristics
over recommended operating free-air temperature range, V
CC
=15V, f=10kHz (unless otherwise noted)
Reference Section
Value
Parameter Test
conditions*
Min Typ** Max
Units
Output voltage (V
ref
) l
O
= 1mA
4.75
5
5.25
V
Input regulation
V
CC
= 7V to 40V
2
25
Output regulation
I
O
= 1mA to 10mA
1
15
mV
Output voltage change with temperature
T
A
= MIN to MAX
0.2 1 %
Short-circuit output current***
V
ref
= 0
35
mA
Oscillator Section
(see Figure 1)
Value
Parameter Test
conditions*
Min Typ** Max
Units
Frequency
C
T
= 0.01
F, R
T
= 12k
10 kHz
Standard deviation of frequency ****
All values of V
CC
, C
T
, R
T
, and T
A
constant
10
Frequency change with voltage
V
CC
= 7V to 40V, T
A
= 25C
0.1
Frequency change with temperature *****
C
T
= 0.01
F, R
T
= 12k
,
T
A
= MIN to MAX
1
%
Amplifier Section
(see Figure 2)
Value
Parameter Test
conditions*
Min Typ** Max
Units
Input offset voltage
V
O
(pin 3) = 2.5V
2
10
mV
Input offset current
V
O
(pin 3) = 2.5V
25
250
nA
Input bias current
V
O
(pin 3) = 2.5V
0.2
1
A
Common-mode input voltage range
V
CC
= 7V to 40V
-0.3 to V
CC
-2
V
Open-loop voltage amplification
V
O
= 3V, R
L
= 2k
,
V
O
= 0.5 to 3.5V
70 95 dB
Unity-gain bandwidth
V
O
= 0.5 to 3.5V, R
L
= 2k
800
kHz
Common-mode rejection ratio
V
O
= 40V, T
A
= 25C
65 80 dB
Output sink current (pin 3)
V
ID
= -15mV to -5V,
V
(pin3)
= 0.7 V
0.3 0.7 mA
Output source current (pin 3)
V
ID
= 15mV to 5V,
V
(pin3)
= 3.5 V
-2
mA
* For conditions shown as MIN or MAX, use the appropriate value specified under recommended operating conditions.
** All typical values except for parameter changes with temperature are at T
A
=
25 C
*** Duration of the short-circuit should not exceed one second.
**** Standard deviation Is a measure of the statistical distribution about the mean as derived from the formula
2
/
1
1
2
1
)
(
-
-
=
=
N
n
n
N
x
x
***** Temperature coefficient of timing capacitor and timing resistor not taken into account
Output section
Value
Parameter Test
conditions
Min Typ* Max
Units
Collector off-state current
V
CE
=40V, V
CC
=40V
2 100
Emitter off-state current
V
CC
=V
C
=40V, V
E
=0
-100
A
Common-emitter V
E
=0, I
C
=200 mA
1.1
1.3
Collector-emitter saturation voltage
Emitter-follower V
C
=15V, I
E
=-200 mA
1.5
2.5
V
Output control input current
V
I
=V
ref
3.5
mA
Dead-time control-section
(see Figure 1)
Value
Parameter Test
conditions
Min Typ* Max
Units
Input bias current (pin 4)
V
I
=0 to 5.25V
-2
-10
A
Maximum duty cycle, each output
V
I
(pin 4)
=0, C
T
=0.1
F, R
T
=12k
45 %
Zero duty cycle
3
3.3
Input threshold voltage (pin 4)
Maximum duty cycle
0
V
Page 4 of 5
Replacement of
TL494
MIK494
Pulse-Width-Modulation
Controller
September 1995 - revised September 2002
PWM Comparator Section
(see Figure 1)
Value
Parameter Test
conditions
Min Typ* Max
Units
Input threshold voltage (pin 3)
Zero duty cycle
4
4.5
V
Input sink current (pin 3)
V
(pin 3)
= 0.7V
0.3
0.7
mA
Total Device
Value
Parameter Test
conditions
Min Typ* Max
Units
V
CC
=15V 6
10
Standby supply current
Pin 6 at V
ref
, all other inputs and
outputs open
V
CC
=40V 9
15
Average supply current
V
I (pin 4)
=2V, See Figure 1
7.5
mA
Switching Characteristics
, T
A
= 25C
Value
Parameter Test
conditions
Min Typ* Max
Units
Output voltage rise time
Common-emitter configuration,
100
200
Output voltage fall time
See figure 3
25
100
Output voltage rise time
Emitter-follower configuration.
100
200
Output voltage fall time
See Figure 4
40
100
ns
*AII typical values except for temperature coefficient are at T
A
=25
C
Pad Location MIK494
Chip size 2.05x2.3 mm
Pad location coordinates
Coordinates (
m)
Pad
N
Pad Name
X Y
1 NONINV
INPUT
1305
120
2 INV
INPUT
1600
130
3 FEEDBACK
1800
130
4 DEAD-TIME
CONTROL
1810
370
5 C
T
1795
975
6 R
T
1770
1240
7 GND
1520
2135
8 C1
1405
2020
9 E1
1055
2015
10 E2
805
2015
11 C2
460
2020
12 V
CC
140
1410
13 OUTPUT
CONTROL
140
1260
14 REF
OUT
160
375
15 INV
INPUT
250
195
16 NONINV
INPUT
405
195
Page 5 of 5
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