Datasheet

AD534 Data Sheet
Rev. D | Page 16 of 20
09675-018
AD534
+V
S
X
1
X
2
SF
Y
1
Y
2
OUT
Z
1
Z
2
–V
S
+15V
500Ω
39kΩ
2kΩ
82kΩ
2.2kΩ
–15V
C
ONTROL INPUT,
E
C
100mV TO 10V
+
–
(= R)
ADJ
1kHz
0.01
(= C)
ADJ 8kHz
3pF to 30pF
2
3
7
AD211
+15V
OUTPUT
±15V APPROX.
PINS 5, 6, 8 TO +15V
PINS 1, 4 TO –15V
f = ×
E
C
40
1
CR
= 1kHz PER VOLT
WITH VALUES SHOWN
CALIBRATION PROCEDURE:
WITH E
C
= 1.0V, ADJUST POTENTIOMETER TO SET f = 1.000kHz WITH
E
C
= 8.0V, ADJUST TRIMMER CAPACITOR TO SET f = 8.000kHz. LINEARITY
WILL TYPICALLY BE WITHIN ±0.1% OF FS FOR ANY OTHER INPUT.
DUE TO DELAYS IN THE COMPARATOR, THIS TECHNIQUE IS NOT SUITABLE
FOR MAXIMUM FREQUENCIES ABOVE 10kHz. FOR FREQUENCIES ABOVE
10kHz THE AD537 VOLTAGE-TO-FREQUENCY CONVERTER IS RECOMMENDED.
A TRIANGLE-WAVE OF ±5V PK APPEARS ACROSS THE 0.01µF CAPACITOR: IF
USED AS AN OUTPUT, A VOLTAGE-FOLLOWER SHOULD BE INTERPOSED.
Figure 26. Differential Input Voltage-to-Frequency Converter
09675-019
AD534
AD741J
+V
S
X
1
X
2
SF
Y
1
Y
2
OUT
Z
1
Z
2
–V
S
+15V
+15V
10kΩ
10kΩ
10kΩ
20kΩ 10kΩ 10kΩ
ZERO
ADJ
10MΩ
–15V
10µF
NONPOLAR
10µF SOLID Ta
20kΩ
AD741K
5kΩ
+
RMS + DC
MODE
AC RMS
INPUT
5V RMS FS
±
10V PEA
K
OUTPUT
0V TO 5V
M
A
TCHED TO 0.025
%
CALIBRATION PROCEDURE:
WITH MODE SWITCH IN ‘RMS + DC’ POSITION, APPLY AN INPUT OF +1.00V DC.
ADJUST ZERO UNTIL OUTPUT READS SAME AS INPUT. CHECK FOR INPUTS
OF ±10V; OUTPUT SHOULD BE WITHIN ±0.05% (5mV).
ACCURACY IS MAINTAINED FROM 60Hz TO 100kHz, AND IS TYPICALLY HIGH
BY 0.5% AT 1MHz FOR V
IN
= 4V RMS (SINE, SQUARE, OR TRIANGLULAR-WAVE).
PROVIDED THAT THE PEAK INPUT IS NOT EXCEEDED, CREST FACTORS UP
TO AT LEAST 10 HAVE NO APPRECIABLE EFFECT ON ACCURACY.
INPUT IMPEDANCE IS ABOUT 10kΩ; FOR HIGH (10MΩ) IMPEDANCE, REMOVE
MODE SWITCH AND INPUT COUPLING COMPONENTS.
FOR GUARANTEED SPECIFICATIONS THE AD536A AND AD636 ARE OFFERED
AS A SINGLE PACKAGE RMS-TO-DC CONVERTER.
Figure 27. Wideband, High-Crest Factor, RMS-to-DC Converter