IL494A-01 1

TECHNICAL DATA
PWM Control Circuit
IL494A
The IL494 incorporates 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, the IL494 contains an on-chip 5volt regulator, two error amplifiers, adjustable oscillator, dead-time control
comparator, pulse-steering flip-flop, and output-control circuitry. The
uncommitted output transistors provide either common-emitter or emitterfollower output capability. Push-pull or single-ended output operation may be
selected through the output-control function. The architecture of the IL494
prohibits the possibility of either output being pulsed twice during push-pull
operation.
FEATURE






PIN ASSIGNMENT
Complete PWM Power Control Circuitry
Uncommitted Outputs for 200 mA Sink or Source
Output Control Selects Single-Ended or Push-Pull Operation
Internal Circuitry Prohibits Double Pulse at Either Output
Internal Regulator Provides a Stable 5 V Reference Supply
Variable Dead-Time Provides Control Over Total Range
ORDERING INFORMATION
Device
IL494AN
IL494AD
IL494ADT
Operating
Temperature Range
TA = -20 to 85 C
for all packages
Package
Plastic
DIP-16
SOP-16
SOP-16
Shipping
Tube
Tube
Tape& Reel
FUNCTION TABLE
Output Control
Grounded
At Vref
Output Function
Single-ended or Parallel Output
Normal Push-Pull Operation
LOGIC DIAGRAM
July 2009, Ver.01
IL494A
MAXIMUM RATINGS
Symbol
VCC
Parameter
Supply Voltage
Value
Unit
41
V
VI
Amplifier Input Voltage
VCC +0.3
V
VO
Collector Output Voltage
41
V
Collector Output Current
250
mA
-65 to +150
C
Tstg
Storage Temperature
RECOMMENDED OPERATING CONDITIONS
Symbol
VCC
Parameter
Supply Voltage
Min
Max
Unit
7
40
V
-0.3
VCC - 2
V
VI
Amplifier Input Voltage
VO
Collector Output Voltage
40
V
Collector Output Current (Each Transistor)
200
mA
Current Into Feed back Terminal
0.3
mA
CT
Timing Capacitor
0.47
10.000
nF
RT
Timing Resistor
1.8
500
K
1
300
KHz
-20
+85
C
Oscillator Frequency
TA
Operating Free-Air Temperature
July 2009, Ver.01
IL494A
ELECTRICAL CHARACTERISTICS (Temperature -20  85C, VCC = 15 V, f=10 kHz))
Symbol
Parameter
Test Conditions
Min
Max
Unit
4.95
5.05
V
Reference Section
Vref
Output Voltage
IO=1 mA
Vregin
Output regulation
VCC=7 V to 40 V, TA=25C
25
mV
Vregout
Input regulation
IO=1 to 10 mA, TA=25C
15
mV
Vref
Output Voltage change with
temperature
TA= -20C to 85C
1
%
ISC
Short-circuit output current
(Note 1)
Vref=0
50
mA
14
KHz
Oscillator Section
fOSC
Frequency
CT=0.01 F, RT=12 k
fOSC
Standard deviation of
frequency (Note 2)
All values of VCC, CT, RT, TA
Constant
15
%
fOSC(V)
Frequency change with
voltage
VCC= 7 V to 40 V,
TA=25C
10
%
fOSC(T)
Frequency change with
temperature
CT=0.01 F, RT=12 k
TA= -20C to 85C
2
%
-10
A
6
Dead Time Control Section
IIB(2T)
Input bias current (pin 4)
VI= 0 to 5.25 V
DCmax
Maximum duty cycle, each
output
VI(pin 4)=0 V
VTHD
Input threshold voltage
Zero duty cycle
(pin 4)
Maximum duty cycle
45
%
3.3
V
0
Error Amp Section
VIO
Input offset voltage
VO(pin 3)=2.5 V
10
mV
IIO
Input offset current
VO(pin 3)=2.5 V
250
nA
IIB
Input bias current
VO(pin 3)=2.5 V
1
A
Common-mode input
VCC= 7 V to 40 V
voltage range
Avol
fb
CMRR
Open-loop voltage
amplification
LOW
-0.3
HIGH
VCC - 2
VO=3 V, VO=0.5 to 3.5 V
Unity-gain bandwidth
V
70
dB
100
kHz
Common-mode rejection
ratio
VCC=40 V, TA=25C
65
dB
IO
Output sink current (pin 3)
VID=-15 mV to -5 V,
VO(pin 3)=0.7 V
0.3
mA
IO+
Output source current (pin 3)
VID=15 mV to 5 V,
VO(pin 3)=3.5 V
-2
mA
July 2009, Ver.01
IL494A
ELECTRICAL CHARACTERISTICS (Temperature -20  85C, VCC = 15 V, f=10 kHz))
Symbol
Parameter
Test Conditions
Min
Max
Unit
4.5
V
PWM Comparator Section
VTHP
II
Input threshold voltage
(pin 3)
Zero duty cycle
Input sink current (pin 3)
VO(pin 3)=0.7 V
0.3
mA
Switching Characteristics
trc
Output voltage rise time
Common-emitter configuration
200
ns
tfc
Output voltage fall time
Common-emitter configuration
100
ns
trf
Output voltage rise time
Emitter-follower configuration
200
ns
tff
Output voltage fall time
Emitter-follower configuration
100
ns
Output Section
IC(off)
Collector off-state current
VCE=40 V, VCC=40 V
100
A
IE(off)
Emitter off-state current
VCC=VC=40 V, VE=0
-100
A
VSAT
Collectoremitter
Commonemitter
VE=0, IC=200 mA
1.3
V
saturation
voltage
Emitterfollower
VC=15 V, IE=-200 mA
2.5
VI=Vref
3.5
mA
mA
IOCH
Output control input current
Total Device
ICC
ICCA
Standby supply current
Average supply current
All other inputs &
VCC=15 V
10
outputs open
VCC=40 V
15
V(pin 4)=2 V
17
mA
Notes: 1. Duration of the short circuit should not exceed one second.
2. Standard deviation is a measure of the statistical disribution about the mean as derived from the formula
N
 (xn - x)2
n=1
=
N–1
July 2009, Ver.01
IL494A
Typical Application
Pulse Width Modulated Step-down Converter
July 2009, Ver.01
IL494A
Parameter Measurement Information
1.
Dead time and Feedback Control
2.
Error Amplifier Characteristics
3.
Common-Emitter Configuration
4.
Emitter-Follower Configuration
July 2009, Ver.01
IL494A
Typical Performance Curves
FIGURE 1 – OSCILLATOR FREQUENCY vs.
TIMING RESISTANCE
FIGURE 2 – OPEN LOOP VOLTAGE GAIN AND
PHASE vs. FREQUENCY
FIGURE 3 – PERCENT DEAD TIME
vs.OSCILLATOR FREQUENCY
FIGURE 4 – PERCENT DUTY CYCLE vs.
DEAD-TIME CONTROL VOLTAGE
July 2009, Ver.01
IL494A
FIGURE 5 – EMITTER-FOLLOWER
CONFIGURATION OUTPUT-SATURATION
VOLTAGE vs. EMITTER CURRENT
FIGURE 6 – COMMON-EMITTER
CONFIGURATION OUTPUT-SATURATION
VOLTAGE vs. COLLECTOR CURRENT
FUGURE 7 – STANDBY-SUPPLY CURRENT
vs. SUPPLY VOLTAGE
July 2009, Ver.01
IL494A
July 2009, Ver.01