25LC320/S

Overview

The Microchip Technology 25LC320/S is a 32 Kbit (4096 x 8 bit) serial Electrically Erasable PROM. It operates within a voltage range of 2.5V to 5.5V and supports a maximum clock frequency of 2 MHz. The device utilizes a standard SPI-compatible interface with SCK, SI, SO, CS, HOLD, and WP pins. It features low-power CMOS technology with typical standby current of 500 nA and read current of 500 μA. Endurance is rated at 1 million E/W cycles with data retention exceeding 200 years.

Feature Summary

• Supports block write protection for none, 1/4, 1/2, or all array segments via status register configuration.
• Includes built-in power on/off data protection circuitry and a write enable latch mechanism.
• Features a hold pin that allows pausing serial communication without resetting the sequence.

Applications

• Microcontroller system data storage
• Configuration memory applications
• Parameter storage in industrial devices

Procurement Notes

Verify the specific package suffix matches the required form factor, as this part number family includes PDIP, SOIC, TSSOP, and 14-lead TSSOP options. Confirm temperature grade requirements against Industrial (-40°C to +85°C) or Automotive (-40°C to +125°C) specifications before ordering. Check datasheet revisions for any functional updates.

Selection Notes

Select this component for designs requiring non-volatile storage accessed via SPI. Ensure the host microcontroller supports the required voltage levels and clock speeds. Consider the 25LC320A series for new designs, as the original 25LC320 is not recommended for new implementations.

Part Context

This device belongs to the 25XX320 family, which also includes the 25AA320 and 25C320 variants. These parts share identical pinouts and instruction sets but differ in operating voltage ranges and maximum clock frequencies. The 25LC320 specifically targets the 2.5V to 5.5V supply range.

Replacement Considerations

Public confirmed substitute part numbers: 25LC320AT-E/SN, 25LC320-I/SN, 25LC320A-I/P, 25LC320A-E/ST.

FAQ

How does the Hold function work?

The HOLD pin suspends transmission during a serial sequence. It must be held high when not in use. Pulling it low pauses communication while keeping the device selected, allowing the host to service interrupts without retransmitting the sequence.

What is the purpose of the Write Protect (WP) pin?

The WP pin works with the WPEN bit in the STATUS register to prohibit writes to nonvolatile bits. When WP is low and WPEN is high, writing to the STATUS register is disabled, providing hardware-level protection.