SEMICONDUCTOR
FA494AP/AF
BIPOLAR LINEAR INTEGRATED CIRCUIT
TECHNICAL DATA
Voltage-Mode PWM Controller IC
The FA494AP/AF 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, this device
offers the systems engineer the flexibility to tailor the power supply control
circuitry to a specific application.
W
Θ
d
P
T
D
The FA494AP/AF contains two error amplifiers, an on-chip adjustable
oscillator, a dead-tme control(DTC) comparator, a pulse-steering control
flip-flop, a 5-V, 5%-precision requlator, and output-control circuits.
The error amplifiers exhibit a common-mode voltage range from -0.3V
to VCC -2V. The dead-time control comparator has a fixed offset that
provides approximately 5% dead time.
DIM MILLIMETERS
A
_
+
A
B
D
d
19 3 0 2
_
9
16
6 45+0 2
_
+
1 52 0 1
_
0 46+0 1
G
0 50 MIN
_
+
3 8 0 3
H
L
The on-chip oscillator may be bypassed by terminating RT to the
reference output and providing a sawtooth input to CT, or it may drive
the common circuits in synchronous multiple-rail power supplies.
The uncommitted output transistors provide either common- emitter or
emitter-follower output capability. The FA494AP/AF provides for push-
pull or single-ended output operation, which may be selected through
the output-control function.
_
+
3 3 0 3
8
1
P
2 54
0 25+0 1/-0 05
7 62
T
W
Θ
0 - 15
DIP-16
The architecture of this device prohibits the possibility of either output
being pulsed twice during push-pull operation.
FEATURES
Completed PWM Power Control Circuitry.
P
L
D
Uncommitted Outputs for 200mA 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 5V Reference Supply With 5% Tolerance.
Circuit Architecture Allows Easy Synchronization.
A
DIM MILLIMETERS
_
16
9
A
B1
B2
D
9 88+0 2
_
+
3 94 0 2
_
6 00 0 3
+
_
+
0 4 0 1
G
0 15+0 1/-0 05
_
+
1 63 0 2
H
_
+
L
0 65 0 2
P
1 27
T
0 20+0 1/-0 05
8
1
MAXIMUM RATINGS (Ta=25
)
ITEM
SYMBOL
VCC
RATING
41
UNIT
V
Supply Voltage
SOP-16
VIN
VCC+0.3
41
Error Amplifier Input Voltage
Collector Output Voltage
Collector Output Current
V
VO
V
IO
250
mA
FUNCTION TABLE
FAC494AP
FAC494AF
750
Power
INPUT TO
PD
mW
OUTPUT FUNCTION
Consumption
400
OUTPUT CTRL
Topr
Tstg
VI=GND
VI=Vref
Operating Temperature
Storage Temperature
Single-ended or paralled output
Normal push-pull operation
-20 85
-25 125
2008. 8. 11
Revision No : 0
1/6