Renesas ICM7228AIPI

Overview

ICM7228AIPI from Intersil is an 8-digit, microprocessor-compatible LED display decoder driver for common anode 7-segment displays. It integrates 8-byte static RAM, on-chip digit/segment drivers, multiplex scan circuitry, and supports Hexadecimal, Code B, and No Decode modes. It operates from a single 5V supply, delivers 200mA digit drive current, and enables independent segment control for bargraph or irregular display formats in instrumentation and test equipment.

For engineers reviewing the ICM7228AIPI datasheet, ICM7228AIPI pinout, ICM7228AIPI application, or ICM7228AIPI equivalent, this device offers fast 200ns write access, non-overlapping digit drive to prevent ghosting, sequential 8-digit or single-digit RAM update, and low-power shutdown mode with 1μA quiescent current - critical for embedded panel displays requiring stable timing and segment-level flexibility.

Technical Context

The ICM7228AIPI implements a CMOS-based multiplexed display controller with an internal 390Hz scan oscillator, interdigit blanking (2–10μs), and dual-mode decoding logic. Its control register configures display format (Hex/Code B/No Decode), RAM bank selection (A/B), and shutdown via ID4–ID7 inputs under MODE = High.

Data entry occurs in three modes: Control Register update only, sequential 8-digit RAM load (triggered by ID7 = High), or single-digit update (using ID0–ID2 as digit address). In No Decode mode, ID0–ID7 directly map to 7 segments + decimal point, enabling full 64-segment control without decoding logic.

Key Specifications

Pinout & Package

ICM7228AIPI is housed in a 28-lead PDIP package (Package Drawing E28.6), lead pitch 0.3 inch, through-hole mountable. Pin assignments are identical to ICM7228AIBI and ICM7228AIBIZ, supporting common-anode LED displays.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar LED display driver applications.

Compared with ICM7228AIPIZ, the original ICM7228AIPI offers identical performance but lacks Pb-free finish; compared with ICM7218AIPI, it adds No Decode mode, 200ns write speed, and single-digit addressing - enabling richer UI capabilities in space-constrained instrumentation.

Availability

ICM7228AIPI is available at Aetrix Electronics and suitable for instrumentation panels, handheld test equipment, and industrial panel meters requiring stable component supply across extended temperature ranges and long production lifecycles.

Supply support for ICM7228AIPI 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

Intersil (now part of Renesas Electronics) is a semiconductor manufacturer specializing in precision analog, power management, and interface ICs for industrial and embedded systems.

The ICM7228 product line was designed specifically for microprocessor-driven LED display systems requiring integrated RAM, flexible decoding, and robust segment/digit drive - targeting instrumentation, test gear, and panel meter applications.

FAQ

What display types does the ICM7228AIPI support?

The ICM7228AIPI supports common anode 7-segment LED displays with decimal point. It drives up to 8 digits using integrated digit and segment drivers, and is not compatible with common cathode or LCD displays. Its output architecture is optimized for direct connection to standard through-hole or surface-mount LED modules without external current-limiting resistors.

Does the ICM7228AIPI require an external clock source?

No, the ICM7228AIPI includes an internal multiplex oscillator operating at approximately 390Hz per digit. This eliminates the need for external timing components and ensures synchronized, non-overlapping digit scanning - critical for eliminating ghosting in multiplexed LED displays.

How does the No Decode mode function in the ICM7228AIPI?

In No Decode mode, the ICM7228AIPI bypasses its hexadecimal and Code B decoders, allowing direct mapping of ID0–ID7 inputs to individual LED segments (a–g + DP). This enables precise control for bargraphs, status indicators, or custom symbols - with ID7 controlling the decimal point in active-low fashion.

Can the ICM7228AIPI retain display data during power-down?

Yes, the ICM7228AIPI retains data in its 8-byte static RAM down to a supply voltage of 2V. In shutdown mode (ID4 = Low), quiescent current drops to 1μA typical, preserving display content while minimizing system power - ideal for battery-backed instrumentation and portable devices.

What are the key timing requirements for writing to the ICM7228AIPI?

The ICM7228AIPI requires a minimum 200ns WRITE pulse width (tWL), 250ns data setup time (tDS), and zero hold time for data and MODE. These specifications enable direct memory-mapped I/O interfacing with most 5V microcontrollers (e.g., 8051, PIC18) without wait-state insertion or glue logic.