AD652SQ Analog Devices Inc, AD652SQ Datasheet
AD652SQ
Specifications of AD652SQ
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AD652SQ Summary of contents
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... The 16-lead CERDIP-packaged AQ and BQ grades are specified for operation over the −40°C to +85°C industrial temperature range. The AD652SQ is available for operation over the full −55°C to +125°C extended temperature range. PRODUCT HIGHLIGHTS 1 ...
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AD652 TABLE OF CONTENTS Specifications..................................................................................... 3 Absolute Maximum Ratings............................................................ 5 ESD Caution.................................................................................. 5 Definitions of Specifications ....................................................... 5 Theory of Operation ........................................................................ 6 Overrange ...................................................................................... 8 SVFC Connection for Dual Supply, Positive Input Voltages .. 9 SVFC Connections for Negative ...
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SPECIFICATIONS Typical @ T = 25° ±15 V, unless otherwise noted. Specifications in boldface are 100% tested at final test and are used to measure A S outgoing quality levels. Table 1. Parameter VOLTAGE-TO-FREQUENCY MODE Gain Error f ...
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AD652 Parameter COMPARATOR Input Bias Current Common-Mode Voltage CLOCK INPUT Maximum Frequency Threshold Voltage (Referred to Pin 12 MIN MAX Input Current (−V < V < CLK S Voltage Range Rise Time OUTPUT STAGE ...
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ABSOLUTE MAXIMUM RATINGS Table 2. Parameter Total Supply Voltage +V to − Maximum Input Voltage (Figure 6) Maximum Output Current (Open Collector Output) Amplifier Short-Circuit to Ground Storage Temperature Range: CERDIP Storage Temperature Range: PLCC ESD CAUTION ESD ...
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AD652 THEORY OF OPERATION A synchronous VFC is similar to other voltage-to-frequency converters in that an integrator is used to perform a charge- balance of the input signal with an internal reference current. However, rather than using a one-shot as ...
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Figure 4 shows that the period between output pulses is constrained exact multiple of the clock period. Consider an input current of exactly one quarter the value of the reference current. In order ...
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AD652 Another way to view this is that the output is a frequency of approximately one-quarter of the clock that has been phase modulated. A constant frequency can be thought of as accumulating phase linearly with time at a rate ...
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SVFC CONNECTION FOR DUAL SUPPLY, POSITIVE INPUT VOLTAGES Figure 8 shows the AD652 connection scheme for the traditional dual supply, positive input mode of operation. The ±V range is from ± ±18 V. When + shown ...
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AD652 20kΩ C INT V IN ±5V SVFC CONNECTION FOR BIPOLAR INPUT VOLTAGES A bipolar input voltage of ±5 V can be accommodated by injecting a 250 µA current into Pin 5 (see Figure 10). A −5 V signal provides ...
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– – NC PLCC CONNECTIONS The PLCC packaged AD652 offers additional input resistors not found on the CERDIP-packaged device. These resistors provide the user with additional input voltage ranges. Besides the 10 V range ...
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AD652 This gain trim should be done with an input voltage and the output frequency should be adjusted to exactly 45% of the clock frequency. Since the device settles into a divide-by-2 mode for an input overrange ...
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The one-shot capacitor controls the pulse width of the frequency output. The pulse is initiated by the rising edge of the clock signal. The delay time between the rising edge of the clock and the falling edge of the frequency ...
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AD652 SINGLE-SUPPLY OPERATION In addition to the Digital Ground being connected to –V also possible to connect Analog Ground to –V Thus, the device is truly operating from a single-supply voltage that can range from ...
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FREQUENCY-TO-VOLTAGE CONVERTER The AD652 SVFC also works as a frequency-to-voltage converter. Figure 22 shows the connection diagram for F/V conversion. In this case, the negative input of the comparator is fed the input pulses. Either comparator input may be used ...
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AD652 DECOUPLING AND GROUNDING It is good engineering practice to use bypass capacitors on the supply-voltage pins, and to insert small valued resistors (10 Ω to 100 Ω) in the supply lines to provide a measure of decoupling between the ...
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V1 0V–10V – V2 0V–10V + V OUT FREQUENCY OUTPUT MULTIPLIER The AD652 can serve as a frequency output multiplier when used in conjunction with a standard voltage-to-frequency converter. Figure 23 shows the low cost AD654 VFC being used ...
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AD652 This can be shown in equation form, where f output frequency and f is the AD652 output frequency: OUT 1 MHz ⎛ ⎞ f ⎜ ⎟ C ⎜ ⎟ ...
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AD652 4 SYNCHRONOUS 0.02µF VOLTAGE-TO- 5 FREQUENCY CONVERTER IN2 8 15pF –V S TIM 9904A TANK 1 2 TANK 2 XTAL 2 3 GND 1 XTAL 4 7.4µH 4 ...
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AD652 SVFC Demultiplexer The demultiplexer needed to separate the combined signals is shown in Figure 30. A phase-locked loop drives another 4-phase clock chip to lock onto the reconstructed clock signal. The sync pulses are distinguished from the data pulses ...
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S 1 VOLTS 2 OUT AD652 4 SYNCHRONOUS 0.02µF VOLTAGE-TO- 5 FREQUENCY CONVERTER –V S +5V 1.5kΩ DRIVER 1 2 10kΩ 1.2kΩ 3 6.8kΩ AD589 1.2V –15V 7915 REG –15V LO ...
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AD652 ISOLATED FRONT END In some applications, it may be necessary to have complete galvanic isolation between the analog signals being measured and the digital portions of the circuit. The circuit shown in Figure 32 runs off a single 5 ...
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DELTA MODULATOR The circuit of Figure 34 shows the AD652 configured as a delta modulator. A reference voltage is applied to the input of the integrator (Pin 7), which sets the steady state output frequency at one-half of the AD652 ...
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AD652 BRIDGE TRANSDUCER INTERFACE The circuit of Figure 38 illustrates a simple interface between the AD652 and a bridge-type transducer. The AD652 is an ideal choice because its buffered 5 V reference can be used as the bridge excitation, thereby ...
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OUTLINE DIMENSIONS 0.200 (5.08) 0.200 (5.08) 0.125 (3.18) 0.048 (1.21) 0.042 (1.07) 0.048 (1.21) 0.042 (1.07) 0.020 (0.50) R 0.358 (9.09) 0.342 (8.69) 0.005 0.098 (2.49) 0.310 (7.87) (0.13) MAX MIN 0.220 (5.59 PIN 0.060 ...
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... AD652SE/883B 50 ppm/°C max 2 AD652SQ 50 ppm/°C max 2 AD652SQ/883B 50 ppm/°C max Plastic Leaded Chip Carrier CERDIP Leadless Chip Carrier. 2 For details on grade and package offerings screened in accordance with MILSTD-883, refer to the Analog Devices Military Products Databook or current AD652/883 data sheet. ...
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NOTES Rev Page AD652 ...
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AD652 NOTES © 2004 Analog Devices, Inc. All rights reserved. Trademarks and registered trademarks are the property of their respective owners. C00798–0–5/04(C) Rev Page ...