Datasheet
Primary
Powerand
Switches
Power
Transformer
ToSupply
Monitor
ToPWM
Controller
RFCoupling
Transformer
STATUS
DRIVERB
DRIVERA
U2901
EXTCLK
CT
Oscillator
X4
10%
-/+
+/-
E/A
1.5V
Reference
RT
V
IN
-
+
V
IN
COMP
INV
NI
VREF
GND
Supply
Output
SUPPLY
CURRENT
PRIMARY POWER
ANDSWITCHES
POWER
TRANSFORMER
TO
SUPPLY
MONITOR
TOPWM
CONTROLLER
OPTICAL
COUPLER
STATUS
DRIVERB
DRIVERA
EXTCLK
CT RT
OSCILLATOR
1.5V
REFERENCE
10%
X4
E/A
-
+
-/+
+/-
UC2901
V
IN
COMP
INV
NI
VREF
GND
V
IN
UC2901-EP
SLUS709A –DECEMBER 2006–REVISED MARCH 2010
www.ti.com
Figure 5. Feedback-Coupled at Switching Frequency
Figure 6. Optically-Coupled DC Feedback
6 Submit Documentation Feedback Copyright © 2006–2010, Texas Instruments Incorporated
Product Folder Link(s): UC2901-EP