ICL7135 Intersil Device Information

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.

ICL7135 4 and Half A to D converter with BCD Output

ICL7135 Device Information

  • 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

See related delabs projects

ICL8038 Versatile Waveform Generator

The ICL8038 waveform generator is a monolithic integrated circuit capable of producing high accuracy sine, square, triangular, sawtooth and pulse waveforms with a minimum of external components. The frequency (or repetition rate) can be selected externally from 0.001Hz to more than 300kHz using either resistors or capacitors, and frequency modulation and sweeping can be accomplished with an external voltage…. The chip is available in some stores, not in production. (This is another chip of intersil i used for many things – delabs)

ICL8038 Device Information

  • Low Frequency Drift with Temperature 250ppm/oC
  • Low Distortion 1%(SineWave Output)
  • High Linearity 0.1%(Triangle Wave Output)
  • Wide Frequency Range 0.001Hz to 300kHz
  • Variable Duty Cycle 2%to 98%
  • High Level Outputs TTL to 28V
  • Simultaneous Sine, Square, and Triangle Wave Outputs
  • Easy to Use – Just a Handful of External Components Required

Everything You Always Wanted to Know About the ICL8038

ICL8038 Versatile Waveform Generator

Use in Phase Locked Loops – Its high frequency stability makes the ICL8038 an ideal building block for a phase locked loop as shown in Figure 9. In this application the remaining functional blocks, the phase detector and the amplifier, can be formed by a number of available ICs (e.g., MC4344, NE562).

The linearity of input sweep voltage versus output frequency can be significantly improved by using an op amp as shown in Figure 10.

LM311 – Voltage Comparator

The LM111, LM211 and LM311 are voltage comparators that have input currents nearly a thousand times lower than devices like the LM106 or LM710. They are also designed to operate over a wider range of supply voltages: from standard ±15V op amp supplies down to the single 5V supply used for IC logic.

LM311 – Voltage Comparator

LM311 - Voltage Comparator

Both the inputs and the outputs of the LM111, LM211 or the LM311 can be isolated from system ground, and the output can drive loads referred to ground, the positive supply or the negative supply. Offset balancing and strobe capability are provided and outputs can be wire ORed.

  • Operates from single 5V supply
  • Input current: 150 nA max. over temperature
  • Offset current: 20 nA max. over temperature
  • Differential input voltage range: ±30V
  • Power consumption: 135 mW at ±15V

Related Resources –

Voltage Comparator Information And Circuits

This page provides basic information about voltage comparator integrated circuits and is to act as reference material for other circuits. The circuits shown are based on the LM339 Quad Voltage Comparator chip or the LM393 Dual Voltage Comparator chip. These devices are functionally the same. The LM311 Voltage Comparator can be used for these applications as well but it also has a number of unique features.

Comparators and Schmitt Triggers

An LM311 in a comparator circuit is shown at the right, with the pin numbers for the connections. The open-collector output is at pin 7, and the ground for this transistor is at pin 1. It is shown pulled up to the logic voltage of +5 with a 1k resistor, which is typical. The output of the LM311 can sink 8 mA. A comparator’s output is essentially binary, YES or NO.


These devices consist of four independent voltage comparators that are designed to operate from a single power supply over a wide range of voltages. Operation from dual supplies also is possible, as long as the difference between the two supplies is 2 V to 36 V, and VCC is at least 1.5 V more positive than the input common-mode voltage.

Quad General Purpose Differential Comparator – LM339

An application from an old TI datasheet showing the versatility of this comparator. For me it was a workhorse and like LM324 was used in many products.

Quad General Purpose Differential Comparator - LM339
Current drain is independent of the supply voltage. The outputs can be connected to other open-collector outputs to achieve wired-AND relationships.

Differential to TTL convertor using LM339

  • Single Supply or Dual Supplies
  • Wide Range of Supply Voltage:
  • Low Supply-Current Drain Independent of Supply Voltage… 0.8 mA Typ
  • Low Input Bias Current …25 nA Typ
  • Low Input Offset Voltage . . . 2 mV Typ
  • Common-Mode Input Voltage Range Includes Ground
  • Differential Input Voltage Range Equal to Maximum-Rated Supply Voltage . . . ±36 V
  • Low Output Saturation Voltage
  • Output Compatible With TTL, MOS, and CMOS