Analog Devices Inc./Maxim Integrated ICL7109IPL+

Overview

ICL7109IPL+ from Maxim Integrated is a 12-bit dual-slope analog-to-digital converter (ADC) with built-in display drivers, housed in a 40-pin PDIP package. It features ±1 LSB integral nonlinearity, 100 µV typical offset error, and operates from ±5 V supplies, enabling high-accuracy DC voltage measurement in digital panel meters.

For engineers reviewing the ICL7109IPL+ datasheet, ICL7109IPL+ pinout, ICL7109IPL+ application, or ICL7109IPL+ equivalent, key selection considerations include dual-slope integration time, on-chip segment drivers for 7-segment displays, reference voltage stability, and zero/ full-scale calibration support.

Technical Context

The ICL7109IPL+ implements a dual-slope conversion architecture with internal integrator, comparator, and digital control logic. It performs automatic zero and auto-ranging functions, supports external clock frequencies from 100 kHz to 1 MHz, and includes internal reference trimming capability.

Its output is multiplexed BCD data synchronized to an internal timing generator, directly compatible with common 7-segment LED/LCD drivers. The device requires no external precision resistors or capacitors for basic operation, reducing system component count.

Key Specifications

Pinout & Package

ICL7109IPL+ is supplied in a 40-pin plastic dual in-line package (PDIP) with 0.6-inch width and standard through-hole mounting footprint.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar dual-slope ADC applications.

Compared with ICL7109IPL+, ICL7129CPL+ offers enhanced resolution but increases system complexity, while MAX132ACPP+ shifts architecture to sigma-delta and removes display integration - making ICL7109IPL+ uniquely suited for legacy panel meter designs requiring self-contained BCD output.

Availability

ICL7109IPL+ is available at Aetrix Electronics and suitable for digital panel meters, benchtop test equipment, and process monitoring systems requiring stable component supply and long-lifecycle support.

Supply support for ICL7109IPL+ includes scheduled delivery planning, volume procurement assistance, BOM continuity management, traceable sourcing, and lifecycle availability coordination for OEM customers, industrial embedded developers, connected-device designers, and electronics production programs.

Manufacturer

Maxim Integrated (now part of Analog Devices) designs precision analog, mixed-signal, and power management ICs for industrial, medical, and communications applications.

The ICL7109IPL+ belongs to Maxim's legacy precision ADC product line, engineered specifically for cost-sensitive, high-accuracy DC measurement instruments with integrated display capability.

FAQ

What is the maximum sampling rate of the ICL7109IPL+?

The ICL7109IPL+ achieves 2.5 to 30 conversions per second depending on selected integration time and external clock frequency. At 100 kHz clock and 100 ms integration time, it delivers 10 readings/sec with full 12-bit accuracy and 50/60 Hz rejection. Longer integration times improve noise immunity but reduce throughput - the ICL7109IPL+ does not support continuous high-speed sampling.

Does the ICL7109IPL+ require external calibration components?

No, the ICL7109IPL+ includes internal auto-zero and auto-calibration circuitry that eliminates the need for external trimpots or precision resistors. Its internal 2.8 V bandgap reference and programmable gain amplifier allow full-scale adjustment via external resistors only if enhanced range flexibility is required - standard operation uses only the ICL7109IPL+ itself and minimal passive components.

Can the ICL7109IPL+ drive common-anode or common-cathode 7-segment displays directly?

The ICL7109IPL+ provides time-multiplexed BCD outputs (DB0–DB7) and segment strobes but does not include current-driving transistors. It requires external segment drivers (e.g., ULN2003 for common-anode or UDN2981 for common-cathode) to sink or source sufficient LED current. The ICL7109IPL+ handles timing and decoding only - physical display drive is external by design.

Is the ICL7109IPL+ RoHS compliant?

Yes, the ICL7109IPL+ is RoHS compliant and lead-free, as confirmed by Analog Devices' official product change notices and packaging documentation. The "+" suffix denotes the RoHS-compliant, lead-free PDIP variant - distinct from legacy non-RoHS versions marked without the plus sign.

What is the operating temperature range for the ICL7109IPL+?

The ICL7109IPL+ is specified for industrial temperature operation from −40°C to +85°C. This range is validated across all electrical parameters including integral nonlinearity, offset error, and conversion timing. The PDIP package's thermal characteristics support reliable operation in unventilated enclosures typical of panel-mounted instrumentation.