23A256-I/ST

Memory IC Overview

The Microchip Technology 23A256-I/ST is a 256-Kbit Serial SRAM device accessed via a SPI-compatible serial bus. It features a 32,768 x 8-bit organization and supports a maximum clock frequency of 20 MHz. The supply voltage range is 1.5V to 1.95V. Operating temperature spans -40°C to +85°C. It utilizes low-power CMOS technology with standby current up to 4 µA at +85°C. The device is housed in an 8-lead TSSOP package.

Memory IC Feature Summary

• Supports Byte, Page, and Sequential operating modes for flexible data access.
• Includes a HOLD pin to suspend communication without resetting the sequence.
• Compatible with standard SPI interfaces or discrete I/O lines.

Memory IC Applications

• Data logging systems requiring non-volatile-like temporary storage.
• Microcontroller peripheral expansion for additional RAM.
• Industrial control applications within specified temperature ranges.

Memory IC Procurement Notes

Verify the specific suffix 'I' confirms the Industrial temperature range (-40°C to +85°C) and 'ST' denotes the 8-TSSOP package. Confirm the 'A' variant indicates the 1.5V-1.95V supply voltage requirement, distinct from the 'K' variant. Ensure compatibility with system voltage levels before integration.

Memory IC Selection Notes

Select this component when low-voltage operation between 1.5V and 1.95V is required. Choose over the 23K256 variant if the system operates below 2.7V. Consider the HOLD pin functionality if interrupt handling requires pausing serial transactions. Verify SPI master compatibility with the device's clock polarity and phase requirements.

Memory IC Part Context

This part belongs to the 23X256 family of 256-Kbit Serial SRAMs. It shares architectural similarities with the 23K256 but differs primarily in supply voltage specifications. The family supports various packages including PDIP, SOIC, and TSSOP. It is designed for direct interfacing with popular microcontroller families.

Memory IC FAQ

How does the HOLD pin function during serial communication?

The HOLD pin suspends transmission when pulled low while SCK is low. Transitions on SI, SCK, and SO are ignored until HOLD is released high, allowing the host to service higher priority interrupts without retransmitting the sequence.

What is the difference between Page mode and Sequential mode?

Page mode limits read/write operations within a 32-byte page boundary, wrapping the internal address counter upon reaching the end. Sequential mode ignores page boundaries, automatically incrementing the address across the entire array until it rolls over to zero.