Microchip Technology AT93C46D-TH-T

Overview

AT93C46D-TH-T from Microchip Technology is a 1-Kbit three-wire serial EEPROM with user-selectable memory organization (128 × 8 or 64 × 16), operating from 1.8V to 5.5V, rated for -40°C to +85°C, and featuring 1,000,000 write cycles and 100-year data retention. It serves as nonvolatile configuration storage in embedded controllers, power management units, and sensor calibration modules.

For engineers reviewing the AT93C46D-TH-T datasheet, AT93C46D-TH-T pinout, AT93C46D-TH-T application, or AT93C46D-TH-T equivalent, key selection considerations include ORG-pin–enabled x8/x16 reconfiguration, 2 MHz max clock at 5V, self-timed 5 ms write cycle, industrial temperature rating, and compatibility with space-constrained 8-lead TSSOP packaging.

Technical Context

The AT93C46D-TH-T implements a synchronous three-wire interface (CS/SK/DI/DO) with rising-edge clocking and supports both byte-wide (128 × 8) and word-wide (64 × 16) addressing modes selected via the ORG pin. Its internal architecture includes a high-voltage generation circuit, address register, and output buffer enabling direct read/write without external timing control.

Write operations require explicit EWEN/EWDS command sequencing, and status feedback is provided via DO pin during CS-high transitions after erase/write initiation. The device incorporates Power-on Reset (POR) with 100 µs tPUP delay and supports VCC slew rates ≤ 0.1 V/µs to prevent spurious writes.

Key Specifications

Pinout & Package

AT93C46D-TH-T is supplied in an 8-lead TSSOP package (3.0 mm × 4.4 mm, 0.65 mm pitch), RoHS-compliant and halide-free. Pin 1 is marked by a beveled corner; exposed pad is not present in this variant.

Key Features

Applications

Equivalent & Alternatives

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

Compared with AT93C46E-TH-T, the AT93C46D-TH-T adds hardware-selectable memory width at no cost in package size or pin count; versus M95128-WMN6TP, it trades density and speed for minimal GPIO usage and deterministic 5 ms write latency - critical for resource-constrained microcontrollers.

Availability

AT93C46D-TH-T is available at Aetrix Electronics and suitable for smart energy meters, industrial PLC I/O modules, and automotive body control units requiring stable component supply, long-lifecycle support, and RoHS-compliant packaging.

Supply support for AT93C46D-TH-T 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 is a global semiconductor company specializing in microcontrollers, analog devices, and memory solutions, with a focus on embedded control and connectivity.

The AT93C46D-TH-T belongs to Microchip's legacy serial EEPROM product line, designed specifically for low-pin-count, low-power, and industrial-grade nonvolatile storage in space-constrained applications.

FAQ

What memory organization options does the AT93C46D-TH-T support?

The AT93C46D-TH-T supports two memory organizations: 128 words × 8 bits or 64 words × 16 bits. Selection is controlled by the ORG pin - tied to VCC for x16 mode, GND for x8 mode, or left floating (defaulting to x16). This hardware-based configuration avoids firmware overhead and ensures deterministic startup behavior in the AT93C46D-TH-T.

Does the AT93C46D-TH-T require external timing components for write operations?

No. The AT93C46D-TH-T features a fully self-timed write cycle with maximum duration of 5 ms. Once a WRITE or ERASE command is issued and data is clocked in, the device internally manages high-voltage generation and programming timing. Host firmware only needs to poll the DO pin for Ready/Busy status after asserting CS - no external capacitors, oscillators, or delay loops are required for the AT93C46D-TH-T.

How is the AT93C46D-TH-T protected against accidental writes during power-up?

The AT93C46D-TH-T integrates a Power-on Reset (POR) circuit that holds the device in a non-responsive state until VCC crosses the 1.5 V threshold and stabilizes. After stabilization, the host must wait ≥100 µs (tPUP) before issuing commands. Additionally, all write operations require explicit EWEN instruction - the AT93C46D-TH-T powers up in EWDS (write-disabled) state, preventing unintended writes during brown-out or reset conditions.

Can the AT93C46D-TH-T operate reliably at 1.8V supply voltage?

Yes. The AT93C46D-TH-T is fully specified for 1.8V to 5.5V operation, including DC and AC characteristics. At 1.8V, it supports up to 250 kHz clock frequency, 1000 ns output delays, and 1.0 µA standby current. This makes the AT93C46D-TH-T suitable for battery-powered or energy-harvesting systems where ultra-low-voltage operation is essential.

What is the function of Pin 7 (NC) on the AT93C46D-TH-T?

Pin 7 on the AT93C46D-TH-T is designated NC (No Connect) - it is not bonded internally and has no electrical function. It may be left floating, tied to GND, or connected to VCC based on PCB layout requirements (e.g., thermal relief or mechanical stability). Unlike the ORG pin (Pin 6), Pin 7 must never be used for signal routing or biasing, as it provides no connectivity in the AT93C46D-TH-T die.