Microchip Technology 93AA46A-I/P

Overview

93AA46A-I/P from Microchip Technology Inc. is a 1 Kbit (128 × 8-bit) low-voltage serial EEPROM with Microwire-compatible 3-wire interface, 1.8–5.5 V supply range, and industrial temperature rating (–40°C to +85°C). It features self-timed erase/write cycles, automatic erase-all-before-write-all (ERAL/WRAL), and Ready/Busy status signaling via DO pin. Used for nonvolatile parameter storage in embedded controllers, sensor calibration modules, and power management ICs.

For engineers reviewing the 93AA46A-I/P datasheet, 93AA46A-I/P pinout, 93AA46A-I/P application, or 93AA46A-I/P equivalent, key selection criteria include its dedicated 8-bit organization (no ORG pin), PDIP-8 package, 1 million erase/write endurance, >200-year data retention, and compatibility with low-power microcontroller SPI-like serial masters requiring hardware-level write protection and status polling.

Technical Context

The 93AA46A-I/P implements a synchronous serial Microwire protocol with start-bit detection, opcode-driven instruction set (READ, WRITE, ERASE, ERAL, WRAL, EWEN/EWDS), and clock-synchronized data transfer on rising CLK edges. All operations are initiated by CS high-to-low transitions followed by precise clocked bit sequences.

It uses internal auto-erase-before-write logic and power-on reset circuitry that inhibits programming below 1.5 V. The device powers up in EWDS (Erase/Write Disable) mode, requiring explicit EWEN before any erase or write - a hardware-enforced safety mechanism independent of software state.

Key Specifications

Pinout & Package

93AA46A-I/P is supplied in an 8-lead PDIP (Plastic Dual In-line Package) with 0.3-inch body width and through-hole mounting. Pin 1 is marked by laser dot or notch; package is RoHS-compliant with matte tin (Pb-free) finish.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar serial EEPROM applications.

Compared with 93LC46A-I/P, the 93AA46A-I/P extends operational voltage down to 1.8 V for ultra-low-power designs, while versus AT25010B-PU it trades SPI speed for simpler 3-wire wiring and hardware-ready/busy signaling - critical for resource-constrained MCUs lacking dedicated SPI status registers.

Availability

93AA46A-I/P is available at Aetrix Electronics and suitable for industrial automation, medical instrumentation, and automotive body electronics requiring stable component supply, long-term obsolescence management, and RoHS-compliant through-hole assembly.

Supply support for 93AA46A-I/P 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

Microchip Technology Inc. is a leading provider of microcontroller, analog, and Flash-IP solutions, headquartered in Chandler, Arizona, with global design and manufacturing operations.

The 93XX series EEPROMs were designed specifically for cost-sensitive, low-power embedded systems needing reliable nonvolatile storage with minimal pin count and robust data integrity - targeting applications where SPI overhead or I²C pull-up constraints are prohibitive.

FAQ

What is the memory organization of the 93AA46A-I/P?

The 93AA46A-I/P has a fixed 128 × 8-bit (1 Kbit) organization with no ORG pin. Unlike 'C' variants, it does not support word-size selection - all communication is strictly 8-bit serial, simplifying firmware development and eliminating external ORG pin routing. This is confirmed in the Device Selection Table and Pin Function Table of DS20001749K.

Does the 93AA46A-I/P require an external pull-up resistor on the DO pin?

No - the 93AA46A-I/P DO pin is actively driven during READ and Ready/Busy status reporting, and enters High-Z when CS is low. An external pull-up is unnecessary and may interfere with status sampling. However, if DI and DO are shorted (shared bus), a series resistor (e.g., 10 kΩ) is required to prevent bus conflict during the read dummy-zero phase, as specified in Section 2.2.

How is write protection implemented on the 93AA46A-I/P?

Write protection is implemented via hardware-enforced EWEN/EWDS commands. The 93AA46A-I/P powers up in EWDS (Erase/Write Disable) mode. An explicit EWEN instruction must precede any ERASE or WRITE operation. After completion, issuing EWDS relocks the array. This two-step command sequence prevents accidental writes due to noise or software glitches - a feature confirmed in Sections 2.6 and 3.4 of DS20001749K.

What is the maximum clock frequency supported by the 93AA46A-I/P?

The 93AA46A-I/P supports up to 3 MHz clock frequency when VCC ≥4.5 V (Table 1-2, A1). At 1.8–2.5 V, the maximum is 1 MHz. These limits are process- and voltage-dependent; exceeding them risks command misinterpretation or incomplete writes. The timing parameters TCKH, TCKL, and TDIS scale accordingly across voltage ranges.

Can the 93AA46A-I/P be used in automotive applications?

The 93AA46A-I/P is rated for Industrial temperature (–40°C to +85°C), not Automotive (–40°C to +125°C). While it may function in some under-hood or cabin environments, Microchip does not qualify or guarantee its reliability at +125°C. For automotive use, select the 93AA46A-E/P (E-temp grade) or equivalent AEC-Q100 qualified parts - the 'I' suffix explicitly denotes industrial qualification only.