Microchip Technology AT24C32D-SSHM-B

Overview

AT24C32D-SSHM-B from Microchip Technology is a 32-Kbit I²C-compatible serial EEPROM organized as 4,096 × 8 bits, operating from 1.7V to 5.5V across -40°C to +85°C industrial temperature range, featuring 1 MHz Fast Mode Plus support, hardware write protection (WP), and ultra-low standby current (6 μA max) for nonvolatile data storage in space-constrained embedded systems.

For engineers reviewing the AT24C32D-SSHM-B datasheet, AT24C32D-SSHM-B pinout, AT24C32D-SSHM-B application, or AT24C32D-SSHM-B equivalent, key selection considerations include I²C bus voltage compatibility (1.7–5.5V), page-write timing (≤5 ms), endurance (1M cycles), data retention (100 years), and SOIC-8 package pin mapping with A0/A1/A2 address inputs and open-drain SDA/SCL interface.

Technical Context

The AT24C32D-SSHM-B implements a standard I²C slave protocol with bidirectional SDA and unidirectional SCL lines, supporting Standard (100 kHz), Fast (400 kHz), and Fast Mode Plus (1 MHz at 2.5–5.5V) operation. It uses Schmitt-triggered, noise-filtered inputs and internal pull-downs on A0/A1/A2/WP pins when left floating.

Memory is organized into 128 pages of 32 bytes each, enabling partial-page writes and sequential/random reads. The device incorporates Power-on Reset (POR), software reset via SCL clocking, and hardware write protection that disables all memory writes when WP = VCC.

Key Specifications

Pinout & Package

AT24C32D-SSHM-B is supplied in an 8-lead SOIC package (SOIC-8, 150 mil width), with pin 1 marked by a beveled corner or notch. The package is RoHS-compliant, halide-free, and lead-free.

Key Features

Applications

Equivalent & Alternatives

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

Compared with AT24C32AN-SSHM-B, the AT24C32D-SSHM-B omits AEC-Q100 qualification but matches all electrical and timing specs for industrial use; versus M24C32-WMN6TP, it delivers 2× faster write throughput and 2× shorter write latency at the cost of slightly higher standby current.

Availability

AT24C32D-SSHM-B is available at Aetrix Electronics and suitable for industrial sensor calibration, medical device configuration, smart meter firmware settings, and automotive body control modules requiring stable component supply, long-term lifecycle support, and RoHS-compliant packaging.

Supply support for AT24C32D-SSHM-B 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 U.S.-based semiconductor company specializing in microcontrollers, analog devices, and memory solutions, with ISO 9001-certified manufacturing and global distribution.

The AT24C32D-SSHM-B belongs to Microchip's AT24Cxx family of I²C serial EEPROMs, designed specifically for reliable, low-power nonvolatile data storage in resource-constrained embedded systems across industrial, medical, and consumer markets.

FAQ

What is the maximum I²C clock frequency supported by the AT24C32D-SSHM-B?

The AT24C32D-SSHM-B supports 100 kHz (Standard mode), 400 kHz (Fast mode), and 1 MHz (Fast Mode Plus) I²C clock frequencies. Fast Mode Plus operation requires VCC ≥ 2.5V and is validated up to 1 MHz, enabling faster configuration loading and reduced bus occupancy compared to legacy 400 kHz EEPROMs. This specification is confirmed in DS20006047A, Table 4-3.

Does the AT24C32D-SSHM-B require external pull-up resistors on SDA and SCL lines?

Yes, the AT24C32D-SSHM-B requires external pull-up resistors on both SDA and SCL lines because SDA is open-drain and SCL is an input-only pin. Microchip specifies maximum pull-up values of 10 kΩ for 100 kHz, 4 kΩ for 400 kHz, and 1.3 kΩ for 1 MHz operation to meet rise-time requirements. These values ensure compliance with I²C timing specifications per DS20006047A, Section 4.4.

How does the write-protect (WP) pin function on the AT24C32D-SSHM-B?

When the WP pin of the AT24C32D-SSHM-B is tied to VCC, all write operations-including byte, page, and erase-are inhibited across the entire 32-Kbit memory array. When WP is grounded, normal write operations are enabled. If left floating, WP is internally pulled down to GND, enabling writes-but Microchip recommends hard-wiring WP to avoid noise-induced glitches, as documented in DS20006047A, Section 2.5.

What is the memory organization of the AT24C32D-SSHM-B?

The AT24C32D-SSHM-B organizes its 32,768 bits as 4,096 words of 8 bits each, grouped into 128 pages of 32 bytes. This structure enables efficient 32-byte page writes and supports both random and sequential read modes. Page boundaries align to 32-byte offsets (e.g., addresses 0x0000–0x001F), and partial-page writes are permitted, as specified in DS20006047A, Sections 6 and 7.1–7.2.

Is the AT24C32D-SSHM-B compatible with 1.8V I²C systems?

Yes, the AT24C32D-SSHM-B is fully compatible with 1.8V I²C systems: it operates from 1.7V to 5.5V, supports 100 kHz and 400 kHz modes across this full voltage range, and meets I²C logic-level thresholds (VIL ≤ 0.3×VCC, VIH ≥ 0.7×VCC) at 1.8V. Its 6 μA max standby current and Schmitt-trigger inputs further ensure robust operation in low-voltage embedded designs, per DS20006047A, Tables 4-2 and 4-3.