Datasheet

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+V
IN
15
Q3
Q4
Q2Q1
1
2
Inv Input
NI Input
200 mA 100 mA
5.8 V
100 W
Comp
9
to PWM
Comparator
UC1525A, UC1527A
UC2525A, UC2527A
UC3525A, UC3527A
SLUS191C – FEBRUARY 1997 – REVISED JANUARY 2008
ELECTRICAL CHARACTERISTICS (continued)
+V
IN
= 20 V, and over operating temperature, unless otherwise specified, T
A
= T
J
PARAMETER TEST CONDITIONS MIN TYP MAX UNIT
PWM COMPARATOR
Minimum duty-cycle 0%
Maximum duty-cycle 45% 49%
Zero duty-cycle 0.7 0.9
Input threshold
(4)
V
Maximum duty-cycle 3.3 3.6
Input bias current
(4)
0.05 1.0 µ A
SHUTDOWN
Soft-start current V
SD
= 0 V, V
SS
= 0 V 25 50 80 µ A
Soft-start low level V
SD
= 2.5 V 0.4 0.7
V
Shutdown threshold To outputs, V
SS
= 5.1 V, T
J
= 25 ° C 0.6 0.8 1.0
Shutdown input current V
SD
= 2.5 V 0.4 1.0 mA
Shutdown Delay
(5)
V
SD
= 2.5 V, T
J
= 25 ° C 0.2 0.5 µ s
OUTPUT DRIVERS (each output) (V
C
= 20 V)
I
SINK
= 20 mA 0.2 0.4
Low-level output voltage
I
SINK
= 100 mA 1.0 2.0
I
SOURCE
= 20 mA 18 19 V
High-level output voltage
I
SOURCE
= 100 mA 17 18
Undervoltage lockout V
COMP
and V
SS
= High 6 7 8
V
C
OFF Current
(6)
V
C
= 35 V 200 µ A
Rise Time
(5)
C
L
= 1 nF, T
J
= 25 ° C 100 600
ns
Fall Time
(5)
C
L
= 1 nF, T
J
= 25 ° C 50 300
TOTAL STANDBY CURRENT
Supply Current V
IN
= 35 V 14 20 mA
(4) Tested at f
OSC
= 40 kHz (R
T
= 3.6 k Ω , C
T
= 0.01 µ F, R
D
= 0 Ω .
(5) These parameters, although ensured over the recommended operating conditions, are not 100% tested in production.
(6) Collector off-state quiescent current measured at pin 13 with outputs low for UC1525A and high for UC1527A.
UC1525A Error Amplifier
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Product Folder Link(s): UC1525A, UC1527A UC2525A, UC2527A UC3525A, UC3527A