Datasheet

UC1842A-EP, UC1843A-EP, UC1844A-EP, UC1845A-EP
CURRENT-MODE PWM CONTROLLER
SGLS134D − SEPTEMBER 2002 − REVISED JANUARY 2013
5
POST OFFICE BOX 655303 • DALLAS, TEXAS 75265
electrical characteristics, T
A
= −55_C to 125_C for the UC184xAM-EP, V
CC
= 15 V (see Note 1),
R
T
= 10 kΩ, C
T
= 3.3 nF, and T
A
= T
J
(unless otherwise stated)
PARAMETER TEST CONDITIONS MIN TYP MAX UNITS
PWM Section
Maximum duty cycle
UC1842A, UC1843A 94% 96% 100%
Maximum duty cycle
UC1844A, UC1845A 47% 48% 50%
Minimum duty cycle 0%
Total Standby Current
Start-up current 0.3 0.5 mA
Operating supply current FB = 0 V, SENSE = 0 V 11 17 mA
V
CC
internal zener voltage I
CC
= 25 mA 30 34 V
NOTES: 1. Adjust V
CC
above the start threshold before setting at 15 V.
PARAMETER MEASUREMENT INFORMATION
Error Amp can source and sink up to 0.5 mA and sink up to 2 mA.
Figure 1. Error Amp Configuration