Microchip Technology AT24CS01-SSHM-T

Overview

AT24CS01-SSHM-T from Microchip Technology is a 1-Kbit (128 × 8) I²C-compatible serial EEPROM with factory-programmed 128-bit unique serial number, operating from 1.7V to 5.5V, supporting 100/400 kHz and 1 MHz Fast Mode Plus, and featuring hardware write protection (WP), ultra-low standby current (6 μA max), and industrial temperature range (−40°C to +85°C). It serves as nonvolatile configuration storage in embedded controllers, sensor nodes, and IoT edge devices.

For engineers reviewing the AT24CS01-SSHM-T datasheet, AT24CS01-SSHM-T pinout, AT24CS01-SSHM-T application, or AT24CS01-SSHM-T equivalent, key selection considerations include its guaranteed unique serial number, 5 ms max write cycle, 1 M write-cycle endurance, 100-year data retention, and compatibility with I²C bus topologies supporting up to eight cascaded devices.

Technical Context

The AT24CS01-SSHM-T implements a two-wire I²C slave interface with Schmitt-triggered, noise-filtered SDA/SCL inputs and open-drain bidirectional data transfer. Its internal architecture includes a dedicated 128-bit read-only serial number block-physically isolated from user memory-and a hardware address comparator for A0–A2-based device selection.

It supports standard, fast, and Fast Mode Plus timing with VCC-dependent frequency limits: 400 kHz across 1.7–5.5V, and 1 MHz only at 2.5–5.5V. Write protection is implemented via a dedicated WP pin that disables all array writes when pulled high, and the device enters low-power standby mode after Stop conditions or write completion.

Key Specifications

Pinout & Package

AT24CS01-SSHM-T is supplied in an 8-lead SOIC package (SOIC-8, 150 mil width), with pins arranged per JEDEC MS-012. All pins are CMOS-compatible and support standard I²C bus termination.

Key Features

Applications

Equivalent & Alternatives

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

Compared with AT24C01D-SSHM-T and M24C01-RMN6TP, the AT24CS01-SSHM-T delivers irreplaceable value through its factory-locked 128-bit serial number - enabling zero-touch device onboarding, anti-counterfeiting, and secure firmware binding without adding process steps or external components.

Availability

AT24CS01-SSHM-T is available at Aetrix Electronics and suitable for industrial sensor nodes, smart metering systems, and medical handhelds requiring stable component supply, long-term lifecycle assurance, and guaranteed traceability via embedded serial numbers.

Supply support for AT24CS01-SSHM-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 Inc. is a leading provider of microcontroller, analog, FPGA, and memory solutions, headquartered in Chandler, Arizona, with global design, manufacturing, and sales operations.

The AT24CS01-SSHM-T belongs to Microchip's CS Series Serial EEPROM family, designed specifically to simplify device identification and authentication in mass-deployed embedded systems by embedding a permanent, globally unique serial number alongside standard nonvolatile storage.

FAQ

What is the function of the WP pin on the AT24CS01-SSHM-T?

The WP (Write-Protect) pin on the AT24CS01-SSHM-T controls hardware-level write access to the entire EEPROM array. When WP is connected to VCC, all write operations-including byte, page, and serial number reads-are inhibited. When WP is grounded, normal read/write functionality is enabled. The pin is internally pulled down, but Microchip recommends hardwiring it to a known state to prevent noise-induced misbehavior. This feature ensures robust protection against unintended writes during power transients or firmware errors in the AT24CS01-SSHM-T.

Does the AT24CS01-SSHM-T support 1 MHz I²C communication?

Yes, the AT24CS01-SSHM-T supports 1 MHz Fast Mode Plus (FM+) I²C operation-but only when VCC is between 2.5V and 5.5V. At lower supply voltages (1.7V to 2.5V), maximum speed is limited to 400 kHz. The device automatically adapts to the host's clock rate within these constraints, and all AC timing parameters-including tLOW, tHIGH, and tBUF-are fully specified for both modes in the official datasheet for the AT24CS01-SSHM-T.

How is the 128-bit serial number accessed on the AT24CS01-SSHM-T?

The 128-bit serial number on the AT24CS01-SSHM-T is accessed via a separate I²C device address: while user memory uses device type identifier '1010' (0xAx), the serial number block uses '1011' (0xBx) in bits 7–4 of the address byte. It is read-only, factory-programmed, and occupies a dedicated memory region outside the 1-Kbit user array-so accessing it does not consume user storage or require special unlock sequences in the AT24CS01-SSHM-T.

What is the maximum write endurance and data retention for the AT24CS01-SSHM-T?

The AT24CS01-SSHM-T is rated for 1,000,000 write cycles and 100 years of data retention at 55°C - verified through qualification testing per Microchip's standards. These values apply to both byte and page write operations under specified VCC and temperature conditions. The endurance and retention specifications are guaranteed across the full industrial temperature range and are integral to the AT24CS01-SSHM-T's suitability for long-lifecycle embedded deployments.

Can multiple AT24CS01-SSHM-T devices share the same I²C bus?

Yes, up to eight AT24CS01-SSHM-T devices can operate on a single I²C bus using hardware address pins A0, A1, and A2. Each pin can be tied to GND or VCC to configure a unique 3-bit slave address, resulting in eight distinct I²C addresses (0x50–0x57). This cascading capability enables scalable system designs - for example, multiple sensor modules or peripheral boards - without requiring additional I²C buses or multiplexers in systems using the AT24CS01-SSHM-T.