RC4200
Divider Circuit with Offset Adjustment
+VREF
PRODUCT SPECIFICATION
R1
VX
(Input)
+VS
+VS
YOS
R18
-VS
R5
X OS
-VS
R21 = Rb
R19
R20
Ra
Rb
Rc
R AX
8
5
VX (Offset)
I1
I4
R6
R8
7
RC4200
R7
Multiplier
1
0.1 µF I2
4
2
R9
0.1 µ F
3
6 I3
-VS
R10
R11
Rd
R4
VZ
(Input)
+VS
R12
R13 Z OS
VZ (Offset)
-VS
RO
VO
(Output)
Rao
R18-R21 can be used in place of R9 to help
cancel gain error due to resistor product
mis-match (See Appendix 1).
0.1µ F
R14
R16
R15
+VS
R17 V OS
VO (Offset)
-VS
General
10K ≤ R5 = R13 = R17 ≤ 50K
R7 + R8 ≈ R1 | | Ra | | Raz | | Rao
R6 ≈ R7 (VS/0.05)
R9 = Rb
R10 ≈ 100 x R4
R11 = 20K
R12 = 100K
R14 + R15 ≈ R0 | | Rc
R16 ≈ R15 (VS/0.10)
Example: Two-Quad Divider
V0 = K(VX/VZ), K = k, VREF = +VS = +15V
-10 ≤ VX ≤ +10, therefore ∆VX = 20
0 ≤ VZ ≤ +10, therefore ∆VZ = 20
-10 ≤ V0 ≤ +10, therefore ∆V0 = 20
R0 = 26.7K
R1 = 333K
Rb = 60K
R5, R13, R17 = 10K
R4 = 50K
R7, R15 = 1K
Rc = 37.5K
R8, R11 = 20K
Rd = 300K
R6, R9, R16 = 300K
Ra = 187.5K
R10 = 4.7M
Raz = 31.25
R12 = 100K
Rao = 133K
65-1878
Figure 7. Divider Circuit with Offset Adjustment
8
REV. 1.2.1 6/14/01