UC1907
UC2907
UC3907
V
CC
0-20mA
ISOLATED
CONTROL
UC3907
DRIVE
AMPLIFIER
–
12
1.0V
9
I
0-4V
DIRECT
CONTROL
VOLTAGE ERROR
AMPLIFIER
SET
(+) SENSE
+
20k
50k
11
7
–
8
V
RANGE 2.0V-2.1V
REF
+
MASTER
INDICATE
REF
1.75V
V
CC
16
V
CC
1.750V
REF
10
0.250V
GND
ADJUST AMPLIFIER
+
–
BUFFER
AMPLIFIER
AMPLIFIER
50mV
+
CURRENT
SHARE
BUS
–
–
(–) SENSE
15
+
20X
–
4
6
+
+
10k
ARTIFICIAL GND
2
3
14
1
13
5
C/S OUT ADJ IN
PWR RET
CURRENT
SENSE
ADJ
COMP
+
–
TO PWR
RETURN
FROM LOAD
MODULE LOAD CURRENT
UDG-99053
Figure 2. Load share connection diagram.
UDG-94105
Figure 3. UC3907 In a load-sharing feedback loop for an off-line isolated supply.
UNITRODE CORPORATION
7 CONTINENTAL BLVD. • MERRIMACK, NH 03054
TEL. (603) 424-2410 • FAX (603) 424-3460
6
TI [ TEXAS INSTRUMENTS ]
