CAT524 Datasheet, PDF (8/12 Pages) Catalyst Semiconductor – Configured Digitally Programmable Potentiometer (DPP™): Programmable Voltage Applications

CAT524
APPLICATION CIRCUITS (Cont.)
+5V
VREF
VDD
VREFH
FINE ADJUST
DPP
RC
=
——^VR—^E—^F —
256 _* 1 µA
Fine adjust gives ± 1 LSB change in V _OFFSET
when VOFFSET =
—^VR—^E—^F
2
127RC
COARSE ADJUST
DPP
+V
RC
V _{OFFSET +}
–
GND
VREFL
+5V
+VREF
VDD
VREFH
FINE ADJUST
DPP
COARSE ADJUST
DPP
GND
VREFL
-RVEF
127RC
RC
RC = ⁽—^+V—^R—^EF—⁾¹â€”^- _µ⁽—^VAO—^FF—^S—^ET—⁺—⁾
Ro = ⁽—^-V—^RE—^F—⁾ ₁₊—_µ⁽—^VAO—^FF—^S—^ET—⁺—⁾
+V
Ro
VOFFSET ₊
–
-V
Coarse-Fine Offset Control by Averaging DPP Outputs
for Single Power Supply Systems
V+
Coarse-Fine Offset Control by Averaging DPP Outputs
for Dual Power Supply Systems
28 - 32V
CONTROL
& DATA
I > 2 mA
VDD
VREFH
O^CAP^TT⁵5²0⁴5
GND
VREFL
VREF= 5.000V
LT 1029
CONTROL
& DATA
15K
10 µF
1N5231B
VDD
VREFH ^5.1V
CCAATT51244
+
GND
VREFL
–
1.00K
10K
LM 324
4.02 K
MPT3055EL
10 µF
35V
OUTPUT
0 - 25V
@ 1A
Digitally Trimmed Voltage Reference
Digitally Controlled Voltage Reference
Doc. No. 25076-00 Rev. 4/01 M-1
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