Datasheet AD633 (Analog Devices) - 10

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AD633 Data Sheet
Likewise, Figure 16 shows how to implement a divider using a This arrangement forms the basis of voltage-controlled integrators multiplier in a feedback loop. The transfer function for the and oscillators as is shown later in this section. The transfer divider is function of this circuit has the form 1 X1 X2Y1Y2   10  E W V (6) I  (7) E O R 10 V X
R 10kΩ LINEAR AMPLITUDE MODULATOR +15V +15V
The AD633 can be used as a linear amplitude modulator with no
0.1µF 0.1µF
external components. Figure 19 shows the circuit. The carrier
E 1 X1 +V X S 8 R
and modulation inputs to the AD633 are multiplied to produce
10kΩ 7 2 X2 W 7 E
a double sideband signal. The carrier signal is fed forward to the
2 AD633JN 6 3 Y1 Z 6 AD711
Z input of the AD633 where it is summed with the double
0.1µF 3
sideband signal to produce a double sideband with the carrier
4 4 Y2 –VS 5 0.1µF
output.
+15V –15V –15V E
-015
0.1µF W' = –10V
86
EX MODULATION + 1 X1 +VS 8
007
INPUT
Figure 16. Connections for Division
±E E M – 2 X2 W 7 W = M 1+ EC sin ωt AD633JN 10V VARIABLE SCALE FACTOR CARRIER 3 Y1 Z 6 INPUT
In some instances, it may be desirable to use a scaling voltage
EC sin ωt 4 Y2 –VS 5
other than 10 V. The connections shown in Figure 17 increase
0.1µF
18 0 6- the gain of the system by the ratio (R1 + R2)/R1. This ratio is
–15V
78 00 limited to 100 in practical applications. The summing input, S, Figure 19. Linear Amplitude Modulator can be used to add an additional signal to the output, or it can
VOLTAGE-CONTROLLED, LOW-PASS AND HIGH-
be grounded.
PASS FILTERS +15V
Figure 20 shows a single multiplier used to build a voltage-
0.1µF + 1 X1 +V
controlled, low-pass filter. The voltage at Output A is a result of
S 8 X INPUT (X1 – X2)(Y1 – Y2) R1 + R2
filtering ES. The break frequency is modulated by EC, the control
– 2 X2 W 7 W = + S AD633JN R1 10V R1
input. The break frequency, f2, equals
+ 3 Y1 Z 6 1kΩ ≤ R1, R2 ≤ 100kΩ Y INPUT
E
– 4 Y2 –V R2 S 5
f C  (8) 2
0.1µF
10 ( 2 RC )
S
6 -01 and the roll-off is 6 dB per octave. This output, which is at a 786
–15V
00 high impedance point, may need to be buffered. Figure 17. Connections for Variable Scale Factor
dB f2 f1 CURRENT OUTPUT 0 f +15V
The voltage output of the AD633 can be converted to a current
–6dB/OCTAVE OUTPUT B
output by the addition of a resistor, R, between the W and Z pins of
0.1µF OUTPUT A 1 X1 +VS 8
the AD633 as shown in Figure 18.
CONTROL INPUT E 1 + T C 1P 2 X2 W 7 OUTPUT B = +15V 1 + T AD633JN 2P R SIGNAL 1 3 Y1 Z 0.1µF 6 OUTPUT A = INPUT ES 0.1µF 1 + T2P + 1 X1 +VS 8 C X 4 Y2 –V 1 S 5 R T = = RC INPUT 1 (X1 – X2)(Y1 – Y2) 1 ω – 1 2 X2 W 7 IO =
9
AD633JN R 10V 1
01
10RC –15V
6-
T2 = = + 3 Y1 Z 6 1kΩ ≤ R ≤ 100kΩ ω2 EC
078
Y
0
INPUT
Figure 20. Voltage-Controlled, Low-Pass Filter
– 4 Y2 –VS 5 0.1µF
7 1 0 The voltage at Output B, the direct output of the AD633, has the 6-
–15V
78 same response up to frequency f 00 1, the natural breakpoint of RC Figure 18. Current Output Connections filter, and then levels off to a constant attenuation of f1/f2 = 10/EC 1 f  (9) 1 2  RC Rev. K | Page 10 of 20 Document Outline FEATURES APPLICATIONS FUNCTIONAL BLOCK DIAGRAM GENERAL DESCRIPTION PRODUCT HIGHLIGHTS TABLE OF CONTENTS REVISION HISTORY SPECIFICATIONS ABSOLUTE MAXIMUM RATINGS THERMAL RESISTANCE ESD CAUTION PIN CONFIGURATIONS AND FUNCTION DESCRIPTIONS TYPICAL PERFORMANCE CHARACTERISTICS FUNCTIONAL DESCRIPTION ERROR SOURCES APPLICATIONS INFORMATION MULTIPLIER CONNECTIONS SQUARING AND FREQUENCY DOUBLING GENERATING INVERSE FUNCTIONS VARIABLE SCALE FACTOR CURRENT OUTPUT LINEAR AMPLITUDE MODULATOR VOLTAGE-CONTROLLED, LOW-PASS AND HIGH-PASS FILTERS VOLTAGE-CONTROLLED QUADRATURE OSCILLATOR AUTOMATIC GAIN CONTROL (AGC) AMPLIFIERS MODEL RESULTS EXAMPLES OF DC, SIN, AND PULSE SOLUTIONS USING MULTISIM EXAMPLES OF DC, SIN, AND PULSE SOLUTIONS USING PSPICE EXAMPLES OF DC, SIN, AND PULSE SOLUTIONS USING SIMETRIX EVALUATION BOARD OUTLINE DIMENSIONS ORDERING GUIDE