Microchip Technology AT93C46-10PI

Overview

AT93C46-10PI from Microchip Technology (formerly Atmel) is a 1K-bit serial EEPROM with 3-wire interface, user-selectable 128 × 8 or 64 × 16 organization, and industrial-grade operation from −40°C to +85°C. It supports 2.7V–5.5V supply, self-timed 10 ms max write cycle, and 1 million write endurance - used in embedded system configuration storage, sensor calibration data retention, and power-management parameter backup.

For engineers reviewing the AT93C46-10PI datasheet, AT93C46-10PI pinout, AT93C46-10PI application, or AT93C46-10PI equivalent, key selection criteria include voltage range compatibility (2.7V–5.5V), industrial temperature rating, 8-pin PDIP/SOIC/TSSOP package options, and ORG-pin configurable memory organization.

Technical Context

The AT93C46-10PI implements a synchronous 3-wire serial interface (CS, SK, DI/DO) with start-bit–driven instruction protocol and ORG-pin–controlled internal word width. It requires explicit EWEN instruction before WRITE/ERASE and supports READY/BUSY status polling via DO during self-timed operations.

Its architecture enables byte- or word-level access without external erase cycles; all programming instructions (WRITE, ERASE, WRAL, ERAL) are validated only at VCC ≥ 4.5V, while READ remains functional across full 2.7V–5.5V range. The device uses internal pull-up on ORG for x16 default when unconnected - except in 1.8V variants (not applicable here).

Key Specifications

Pinout & Package

AT93C46-10PI is available in 8-pin PDIP (8P3), JEDEC SOIC (8S1), EIAJ SOIC (8S2), and TSSOP (8T) packages. Pin functions are identical across all variants.

Key Features

Applications

Equivalent & Alternatives

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

Compared with M95128-WMN6TP and STK12C68-5LH1, the AT93C46-10PI offers unique ORG-pin flexibility for 8/16-bit alignment, guaranteed 2.7V operation for battery-backed systems, and minimal 3-wire GPIO footprint - making it optimal for resource-constrained industrial microcontrollers.

Availability

AT93C46-10PI is available at Aetrix Electronics and suitable for industrial sensor calibration storage, embedded system configuration memory, and power management parameter backup requiring stable component supply across extended temperature ranges and multi-decade product lifecycles.

Supply support for AT93C46-10PI 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 acquired Atmel in 2016 and maintains full support for legacy Atmel EEPROMs including the AT93C series. The company specializes in microcontrollers, memory, and analog semiconductors for industrial, automotive, and consumer markets.

The AT93C46-10PI belongs to Microchip's legacy serial EEPROM product line designed for cost-sensitive, low-pin-count embedded systems requiring robust nonvolatile storage with minimal external components and wide voltage/temperature tolerance.

FAQ

What is the maximum clock frequency supported by AT93C46-10PI at 2.7V?

The AT93C46-10PI supports up to 1 MHz SK clock frequency when operated at 2.7V–5.5V supply. This is specified in the AC Characteristics table under fSK parameter, with tSKH/tSKL minimum values of 250 ns at 2.7V–5.5V, corresponding to a 2 MHz theoretical limit - however, the datasheet explicitly lists 1 MHz as the maximum rated frequency for this voltage range. AT93C46-10PI must be clocked within this limit to ensure reliable instruction decoding and data transfer.

Can AT93C46-10PI operate with ORG pin left unconnected?

Yes - AT93C46-10PI includes an internal ~1 MΩ pull-up on the ORG pin, selecting 64 × 16 organization when unconnected. This behavior is confirmed in the datasheet note: "If the ORG pin is left unconnected, then an internal pullup device (of approximately 1 MΩ) will select the x16 organization." This feature applies to all AT93C46 variants except 1.8V versions, and AT93C46-10PI is a 2.7V–5.5V part, so the pull-up is active. AT93C46-10PI thus defaults to x16 mode unless ORG is externally pulled low.

Does AT93C46-10PI require an external erase cycle before writing?

No - AT93C46-10PI performs automatic erase-before-write internally. The datasheet states: "no separate ERASE cycle is required before WRITE," and the WRITE instruction simultaneously erases and programs the target location. Each WRITE command initiates a self-timed operation that first clears the addressed word to all 1s, then writes the new data. AT93C46-10PI achieves this without host intervention, simplifying firmware implementation compared to EEPROMs requiring explicit ERASE commands.

What is the meaning of the "-10PI" suffix in AT93C46-10PI?

The "-10PI" suffix in AT93C46-10PI indicates two key specifications: "10" denotes maximum 10 ms write cycle time, and "PI" specifies Industrial temperature grade (−40°C to +85°C) in a standard 4.5V–5.5V operating range. This distinguishes it from commercial-grade "PC" variants and low-voltage "-2.7" versions. AT93C46-10PI is therefore optimized for ruggedized applications where extended temperature performance and predictable write timing are mandatory.

How does AT93C46-10PI indicate write completion during a WRITE instruction?

AT93C46-10PI outputs READY/BUSY status on the DO pin when CS is brought high after initiating a WRITE. Per the datasheet: "When CS is brought 'high' following the initiation of a WRITE cycle, the DO pin outputs the READY/BUSY status of the part." A logic '1' on DO indicates completion; logic '0' means programming is still in progress. This polling mechanism works only if CS is raised after ≥250 ns low-time (tCS), and AT93C46-10PI does not support interrupt-driven completion notification - status must be actively read.