Datasheet

AD532
Rev. D | Page 13 of 16
Table 6. Adjustment Procedure (Divider or Square Rooter)
Divider Square Rooter
With: Adjust for: With: Adjust: for:
Adjust X Z V
OUT
Z V
OUT
Scale Factor −10 V +10 V −10 V +10 V −10 V
X
0
(Offset) −1 V +0.1 V −1 V +0.1 V −1 V
Repeat if required.
SQUARE ROOT
AD532
20kΩ
(X
0
)
47kΩ
2.2kΩ
10kΩ
1kΩ
(SF)
+V
S
–V
S
+V
S
–V
S
V
OUT
= 10VZ
Z
OUT
Z
V
OUT
X
1
X
2
Y
1
Y
2
00502-016
Figure 18. Square Rooter Connection
The connections for square root mode are shown in Figure 18.
Similar to the divide mode, the multiplier cell is connected in
the feedback of the op amp by connecting the output back to
both the X and Y inputs. The diode D
1
is connected as shown to
prevent latch-up as Z
IN
approaches 0 volts. In this case, the V
OS
adjustment is made with Z
IN
= +0.1 V dc, adjusting V
OS
to
obtain −1.0 V dc in the output, V
OUT
= −√
10 V Z
. For optimum
performance, gain (S.F.) and offset (X
0
) adjustments are recom-
mended as shown and explained in Table 6.
DIFFERENCE OF SQUARES
AD532
20kΩ
+V
S
–V
S
+V
S
–V
S
V
OS
V
OUT
X
1
X
2
Y
1
Y
2
Z
OUT
20kΩ20kΩ
10kΩ
–Y
X
Y
(OPTIONAL)
V
OUT
=
X
2
– Y
2
10V
AD741KH
00502-017
Figure 19. Differential of Squares Connection
The differential input capability of the AD532 allows for the
algebraic solution of several interesting functions, such as the
difference of squares, X
2
− Y
2
/10 V. As shown in Figure 19, the
AD532 is configured in the square mode, with a simple unity
gain inverter connected between one of the signal inputs (Y)
and one of the inverting input terminals (−Y
IN
) of the multiplier.
The inverter should use precision (0.1%) resistors or be otherwise
trimmed for unity gain for best accuracy.