CAT525 CATALYST [Catalyst Semiconductor], CAT525 Datasheet - Page 8

• Manufacturer Part Number: CAT525
• Manufacturer: CATALYST [Catalyst Semiconductor]

CONTROL
& DATA
CAT525
APPLICATION CIRCUITS (Cont.)
Doc. No. 25078-00 4/01 - A M-1
Coarse-Fine Offset Control by Averaging DPP Outputs
COARSE ADJUST
+5V
FINE ADJUST
V DD
GND
DPP
DPP
Digitally Trimmed Voltage Reference
V REF
for Single Power Supply Systems
V
V
REF
REF
V DD
GND
OPT 505
CAT525
H
L
127R C
V
V
R C
REF
REF
Fine adjust gives
H
L
when V
V OFFSET
I > 2 mA
R = —————
C 256 1 A
OFFSET
V REF
1 LSB change in V
*
+
–
V+
= ———
+V
LT 1029
V REF
2
V
REF
OFFSET
= 5.000V
8
CONTROL
& DATA
Coarse-Fine Offset Control by Averaging DPP Outputs
COARSE ADJUST
+5V
FINE ADJUST
V DD
GND
DPP
DPP
Digitally Controlled Voltage Reference
+V REF
V
V
REF
REF
CAT525
for Dual Power Supply Systems
V DD
OPT 505
GND
-V REF
H
L
V
V
15K
REF
REF
H
L
127R C
1N5231B
R C
R o
10 µF
5.1V
1.00K
V OFFSET
+
–
LM 324
4.02 K
R = ———————————
R = ———————————
+
–
C
o
+V
-V
(+V
(-V
REF
REF
10K
28 - 32V
) + (V
) - (V
1 A
1 A
MPT3055EL
OFFSET
OFFSET
10 µF
35V
+
+
OUTPUT
)
)
0 - 25V
@ 1A