AD688 Analog Devices, AD688 Datasheet
AD688
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AD688 Summary of contents
Page 1
... Zener or the buffer amplifiers and thus does not increase the temperature drift. 3. Output noise of the AD688 is low – typically 6 V p-p. A pin is provided for broadband noise filtering using an external capacitor. 4. The AD688 is available in versions compliant with MIL- STD-883 ...
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... Exposure to absolute maximum rating conditions for extended periods may affect reliability. –2– unless otherwise noted ) S AD688BQ Min Typ Max Units – –1.5 +1 ...
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... AD688AQ AD688BQ AD688SQ NOTES 1 For details on grade and package offerings screened in accordance with MIL-STD-883, refer to the Analog Devices Military Products Databook or current AD688/883B data sheet Cerdip. *Temperature coefficient specified from 0 to +70 C. THEORY OF OPERATION The AD688 consists of a buried Zener diode reference, amplifi- ers and associated thin-film resistors as shown in the block diagram of Figure 1 ...
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... AD688 APPLYING THE AD688 The AD688 can be configured to provide 10 V reference out- puts as shown in Figure 2a. The architecture of the AD688 pro- vides ground sense and uncommitted output buffer amplifiers which offer the user a great deal of functional flexibility. The AD688 is specified and tested in the configuration shown in Figure 2a. The user may choose to take advantage of other configuration options available with the AD688 ...
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... V and –10 V outputs determine the perform- ance grade of the device. Figure 7. Typical AD688SQ Temperature Drift Each AD688A and B grade unit is tested at –40 C, – +25 C, +50 C, +70 C and +85 C. Each AD688S grade unit is tested at –55 C, –25 C, +25 C, +70 C and +125 C. This ...
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... In the circuit shown, the output of the amplifier would actually volts + V and the voltage at the load would be the desired 10 volts. The AD688 has three amplifiers which can be used to imple- ment Kelvin connections. Amplifier A2 is dedicated to the ground force-sense function while uncommitted amplifiers A3 and A4 are free for other force-sense chores ...
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... Figure 11b. Transient Response 5–10 mA Load REV some applications, a varying load may be both resistive and capacitive in nature connected to the AD688 by a long capacitive cable. Figure 12 displays the output amplifier charac- teristics driving a 1,000 pF, 0-to-10 mA load. Figure 12a. Capacitive Load Transient Response Test Circuit Figure 12b ...
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... As shown in Figure 15, the AD688 is an excellent choice for the control element in a bipolar bridge driver scheme. Transistors Q1 and Q2 serve as series pass elements to boost the current drive capability to the 57 mA required by the typical 350 bridge ...