ICL7135 Intersil Corporation, ICL7135 Datasheet
ICL7135
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ICL7135 Summary of contents
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... CAUTION: These devices are sensitive to electrostatic discharge; follow proper IC Handling Procedures. 1-888-INTERSIL or 321-724-7143 | Copyright © Intersil Corporation 1999 Description The Intersil ICL7135 precision A/D converter, with its multi- plexed BCD output and digit drivers, combines dual-slope conversion reliability with 1 in 20,000 count accuracy and is ideally suited for the visual display DVM/DPM market ...
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... Typical Application Schematic SET V = 1.000V REF - REF 2 100k ANALOG 3 GND 4 0. 100k 100k 100K SIGNAL 9 INPUT 0 + ICL7135 CLOCK IN 28 120kHz ANODE 24 DRIVER 23 TRANSISTORS 22 6 ICL7135 SEVEN 15 SEG. DECODE 5-6 DISPLAY ...
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... Discussion. 5. The temperature range can be extended to 70 the higher leakage of the ICL7135. 6. This specification relates to the clock frequency range over which the lCL7135 will correctly perform its various functions See “Max Clock Frequency” section for limitations on the clock frequency range in a system. ...
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... STROBE 26 RUN/HOLD 25 DIGITAL GND 24 0V POLARITY 23 CLOCK CLOCK 120kHz BUSY 21 LSD MSB FIGURE 2. ICL7135 DIGITAL LOGIC INPUT R C INT BUFFER REF INPUT HIGH ZI A FIGURE 3. ANALOG SECTION OF ICL7135 5 PAD DIG GND C INT ...
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... The reference input must be generated as a positive voltage with respect to COMMON, as shown in Figure 4. Digital Section Figure 5 shows the Digital Section of the ICL7135. The ICL7135 includes several pins which allow it to operate con- veniently in more sophisticated systems. These include: Run/HOLD (Pin 25) When high (or open) the A/D will free-run with equally spaced measurement cycles every 40,002 clock pulses ...
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... MSB MULTIPLEXER FF LATCH LATCH LATCH COUNTERS CONTROL LOGIC CLOCK RUN/ OVER UNDER IN RANGE RANGE HOLD FIGURE 5. DIGITAL SECTION OF THE ICL7135 5-10 V+ 6.8V REF HI ZENER ICL7135 I Z COMMON V- FIGURE 4A. V+ 6.8k V+ 20k ICL8069 REF HI 1.2V REFERENCE ICL7135 COMMON FIGURE 4B ...
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... Rollover Resistor and Diode A small rollover error occurs in the ICL7135, but this can be easily corrected by adding a diode and resistor in series between the INTegrator OUTput and analog COMMON or ground. The value shown in the schematics is optimum for the recommended conditions, but if integrator swing or clock frequency is modifi ...
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... Analog And Digital Grounds Extreme care must be taken to avoid ground loops in the layout of ICL7135 circuits, especially in high-sensitivity cir- cuits most important that return currents from digital loads are not fed into the analog ground line. ...
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... A clock source using an LM311 voltage comparator with positive feedback (Figure 11) could minimize any clock frequency shift problem. The ICL7135 is designed to work from 5V supplies. How- ever negative supply is not available, it can be generated with an ICL7660 and two capacitors (Figure 12). ...
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... DIGIT A/D CONVERTER WITH A MULTIPLEXED COMMON ANODE LED DISPLAY 2 A POL G HI VOLTAGE BUFFER D1 505 +5V 47K 5K 0.02 F 2.5K GATES ARE 7409 0.02 F POL ICL7135 V+ DGND FIGURE 8. ICL7135 PLASMA DISPLAY CIRCUIT ICL7135 150 27 OR 150 26 STROBE 25 R/H 4.7K DIG. GND 24 POL 23 22 CLOCK 21 ...
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... INPUT HI INPUT 0 16k 56k LM311 0. 16k FIGURE 11. LM311 CLOCK SOURCE ICL7135 + 161514 CD4054A STROBE 1311 R/H 25 DIG. GND 24 POL 23 120kC = 3 READINGS/SEC CLOCK 22 CLOCK IN BUSY ...
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... ICL7135 +5V FIGURE 14. COMPLEX ICL7135 TO UART INTERFACE EN 74C157 MC680X MCS650X ICL7135 RUN/ HOLD STROBE FIGURE 16. ICL7135 TO MCS-48, -80, -85 INTERFACE 5-16 RRI DRR DR TBRL ENABLE 74C157 STROBE RUN/HOLD BUSY ...
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... REF • POWER SUPPLY: DUAL +5V to GND V- = -5V to GND • OUTPUT TYPE 4 BCD Nibbles with Polarity and Overrange Bits There is no internal reference available on the ICL7135. An external reference is required due to the ICL7135’s 4 digit resolution. INTEGRATE DE-INTEGRATE PHASE PHASE FIXED ...
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... No license is granted by implication or otherwise under any patent or patent rights of Intersil or its subsidiaries. For information regarding Intersil Corporation and its products, see web site http://www.intersil.com ICL7135 PASSIVATION: Type: Nitride/Silox Sandwich Thickness: 8k Nitride over 7k Silox ICL7135 REF REF BUFF ...