ICL7135: 4 1/2 Digit, BCD Output, A/D Converter

The Intersil ICL7135 precision A/D converter, with its multiplexed 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. The 2.0000V full scale capability, auto-zero, and auto-polarity are combined with true ratiometric operation, almost ideal differential linearity and true differential input. All necessary active devices are contained on a single CMOS lC, with the exception of display drivers, reference, and a clock.

The ICL7135 brings together an unprecedented combination of high accuracy, versatility, and true economy. It features auto-zero to less than 10µV, zero drift of less than 1µV/oC, input bias current of 10pA (Max), and rollover error of less than one count. The versatility of multiplexed BCD outputs is increased by the addition of several pins which allow it to operate in more sophisticated systems. These include STROBE, OVERRANGE, UNDERRANGE, RUN/HOLD and BUSY lines, making it possible to interface the circuit to a microprocessor or UART.

Key Features
  • Accuracy Guaranteed to ±1 Count Over Entire ±20000 Counts (2.0000V Full Scale)
  • Guaranteed Zero Reading for 0V Input
  • 1pA Typical Input Leakage Current
  • True Differential Input
  • True Polarity at Zero Count for Precise Null Detection
  • Single Reference Voltage Required
  • Overrange and Underrange Signals Available for Auto-Range Capability
  • All Outputs TTL Compatible
  • Blinking Outputs Gives Visual Indication of Overrange
  • Six Auxiliary Inputs/Outputs are Available for Interfacing to UARTs, Microprocessors, or Other Circuitry
  • Multiplexed BCD Outputs
  • Pb-Free Available (RoHS Compliant)
Typical Diagram
Application Notes
TitleTypeUpdatedSizeOther Languages
AN9705: A Theoretical View of Coherent SamplingPDF13 Nov 201425 KB
AN9675: Coherent and Windowed Sampling with A/D ConvertersPDF13 Nov 2014160 KB
AN9609: Overcoming Common Mode Range Issues When Using Intersil Integrating ConvertersPDF13 Nov 2014103 KB
AN9510: Basic Analog for Digital DesignersPDF13 Nov 2014285 KB
AN054: Display Driver Family Combines Convenience of Use with Microprocessor InterfaceabilityPDF13 Nov 2014306 KB
AN018: Do's and Don'ts of Applying A/D ConvertersPDF13 Nov 201431 KB
AN017: The Integrating A/D ConverterPDF13 Nov 201499 KB
AN028: Building an Auto-Ranging DMM with the ICL7103A/ICL8052A A/D Converter PairPDF13 Nov 2014149 KB
AN023: Low Cost Digital Panel Meter DesignsPDF13 Nov 2014289 KB
AN016: Selecting A/D ConvertersPDF13 Nov 2014113 KB
AN002: Principles of Data Acquisition and ConversionPDF13 Nov 2014257 KB
Datasheets
TitleTypeUpdatedSizeOther Languages
ICL7135 DatasheetPDF14 Nov 2014511 KB
Order Information
Part NumberPackage TypeWeight(g)PinsMSL RatingPeak Temp (°C)RoHS Status
ICL7135CPI28 Ld PDIP4.3928N/ANA
ICL7135CPIZ28 Ld PDIP4.3928N/ANARoHS
ICL7135 Datasheet 14 Nov 2014
28 Ld PDIP HI-507
ICL7135
AN9705: A Theoretical View of Coherent Sampling 13 Nov 2014
AN9675: Coherent and Windowed Sampling with A/D Converters 13 Nov 2014
AN9609: Overcoming Common Mode Range Issues When Using Intersil Integrating Converters 13 Nov 2014
AN9510: Basic Analog for Digital Designers 13 Nov 2014
AN054: Display Driver Family Combines Convenience of Use with Microprocessor Interfaceability 13 Nov 2014
AN018: Do's and Don'ts of Applying A/D Converters 13 Nov 2014
AN017: The Integrating A/D Converter 13 Nov 2014
AN028: Building an Auto-Ranging DMM with the ICL7103A/ICL8052A A/D Converter Pair 13 Nov 2014
AN023: Low Cost Digital Panel Meter Designs 13 Nov 2014
AN016: Selecting A/D Converters 13 Nov 2014
AN002: Principles of Data Acquisition and Conversion 13 Nov 2014