23A640-I/P

Memory IC Overview

The Microchip Technology 23A640-I/P is a 64 Kbit (8192 x 8-bit) Serial SRAM device accessed via a SPI-compatible serial bus. It operates within a supply voltage range of 1.5 V to 1.95 V and supports industrial temperature ranges from -40°C to +85°C. The device features a maximum clock frequency of 20 MHz, with read currents of 3 mA at 1 MHz and standby current up to 4 µA. It utilizes an 8-lead PDIP package.

Memory IC Feature Summary

• Supports flexible operating modes including byte, page, and sequential read/write operations.
• Includes a HOLD pin to suspend transmission during high-priority interrupts without resetting the sequence.
• Utilizes low-power CMOS technology for efficient power consumption.
• Compatible with standard SPI interfaces for direct connection to microcontrollers.

Memory IC Applications

• Data logging in battery-powered devices
• Configuration storage in embedded systems
• Temporary data buffering in microcontroller applications

Memory IC Procurement Notes

Verify the specific suffix 'I' indicates the Industrial temperature grade (-40°C to +85°C) and 'P' denotes the PDIP package. Confirm the voltage range requirement aligns with the 1.5V to 1.95V specification. Ensure the design accounts for the 8-lead PDIP footprint and through-hole mounting style. Cross-reference the datasheet revision for any updates to electrical characteristics or packaging details before finalizing procurement.

Memory IC Selection Notes

Select this component when a low-voltage (1.7V nominal) serial SRAM is required for industrial environments. Compare against the 23K640 variant if a higher supply voltage (2.7V–3.6V) is necessary. Consider the 8-lead PDIP package constraints for PCB layout. Evaluate the 32-byte page size and sequential mode capabilities against application data throughput needs.

Memory IC Part Context

The 23A640 belongs to the 23X640 family of 64 Kbit Serial SRAMs, which also includes the 23K640. This family provides non-volatile-like temporary storage using volatile SRAM technology accessed via SPI. The 23A640 specifically targets lower voltage applications compared to the 23K640, while sharing identical memory organization and interface protocols.

Memory IC Replacement Considerations

The 23K640 is a functional substitute but requires a 2.7V to 3.6V supply voltage instead of the 23A640's 1.5V to 1.95V range. Other 23X640 variants like 23A640T-I/SN offer surface-mount packages (SOIC/TSSOP) instead of the PDIP form factor.

Memory IC FAQ

How does the HOLD pin function affect serial communication?

The HOLD pin allows the host to pause serial communication by pulling it low while SCK is low. This suspends data transfer without resetting the internal address pointer or requiring retransmission of the command sequence.

What are the available operating modes for the 23A640?

The device supports Byte mode (single byte access), Page mode (access within a 32-byte page boundary), and Sequential mode (continuous access across page boundaries with automatic address increment).