Microchip Technology 23K640-E/P

Overview

23K640-E/P from Microchip Technology Inc. is a 64 Kbit (8192 × 8) low-power SPI Serial SRAM with 32-byte page architecture, 20 MHz max clock frequency, and industrial/automotive temperature support (–40°C to +125°C). It operates from 2.7–3.6 V, draws only 3 mA at 1 MHz read current and ≤4 µA standby current at +85°C, and integrates HOLD functionality for interrupt-safe bus pausing - used in automotive infotainment memory buffering and industrial PLC data logging.

For engineers reviewing the 23K640-E/P datasheet, 23K640-E/P pinout, 23K640-E/P application, or 23K640-E/P equivalent, key selection criteria include its SPI-compatible serial interface, 32-byte page write capability, HOLD pin timing compliance (10 ns setup/hold), VCC range tolerance, and automotive-grade reliability validation per DS22126E.

Technical Context

The 23K640-E/P implements a true SPI-compatible serial bus interface with separate SI (data in) and SO (data out) lines, requiring only CS, SCK, SI, SO, HOLD, VCC, and VSS. Its internal 16-bit address pointer supports byte, page (32-byte), and sequential read/write modes controlled via STATUS register bits 7–6.

It features hardware HOLD functionality that places SO, SI, and SCK into high-impedance state while preserving internal state - enabling host MCU to service higher-priority interrupts without sequence restart. The device powers on in Standby mode (CS = high) and requires no external write-enable signal.

Key Specifications

Pinout & Package

23K640-E/P is housed in an 8-lead Plastic Dual In-line Package (PDIP) with 300-mil body width, RoHS-compliant matte tin plating, and industrial-grade thermal performance.

Key Features

Applications

Equivalent & Alternatives

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

Compared with CY14V101QS-SXIT and FM25V05-G, the 23K640-E/P delivers optimal balance of automotive qualification, predictable 32-byte page write timing, and minimal BOM cost - making it preferred for deterministic, cost-sensitive, and thermally demanding embedded logging where external backup is acceptable.

Availability

23K640-E/P is available at Aetrix Electronics and suitable for automotive telematics, industrial PLCs, medical infusion pumps, and smart energy meter applications requiring stable component supply across extended product lifecycles.

Supply support for 23K640-E/P 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 U.S.-based semiconductor manufacturer specializing in microcontrollers, analog devices, and memory solutions for embedded control applications.

The 23K640 belongs to Microchip's serial SRAM product line, designed specifically for SPI-based memory expansion in resource-constrained, thermally demanding systems requiring automotive-grade reliability and low-power operation.

FAQ

What is the operating voltage range for the 23K640-E/P?

The 23K640-E/P operates from 2.7 V to 3.6 V. This range ensures compatibility with standard 3.3 V logic systems and accommodates typical rail tolerances in automotive and industrial power supplies. Operation outside this range may cause data corruption or functional failure, and is not guaranteed per DS22126E specifications.

Does the 23K640-E/P support true SPI mode 0 (CPOL=0, CPHA=0)?

Yes, the 23K640-E/P supports SPI mode 0: data is sampled on the rising edge of SCK (CPHA=0) and clock idles low (CPOL=0). This matches standard PIC® MCU SPI peripherals and most ARM Cortex-M SPI controllers without requiring mode translation logic or firmware workarounds.

How does the HOLD function behave during an active write sequence in the 23K640-E/P?

When HOLD is asserted low during a write sequence, the 23K640-E/P immediately pauses transmission, places SO, SI, and SCK in high-impedance state, and preserves the internal address pointer. Upon releasing HOLD (high), the device resumes exactly where it left off - ensuring no data loss or address misalignment occurs in the 23K640-E/P.

What is the maximum supported clock frequency for the 23K640-E/P at +125°C?

Per DS22126E Table 1-2, the 23K640-E/P supports up to 16 MHz at VCC = 3.0 V and TA = –40°C to +125°C (Automotive E-grade). At 20 MHz, operation is specified only for industrial temperature (–40°C to +85°C) and VCC ≥ 3.0 V - exceeding this violates AC timing margins in automotive use cases.

Can the 23K640-E/P be used as a direct replacement for the 23A640-I/P?

No - the 23K640-E/P and 23A640-I/P are not interchangeable. They differ in supply voltage (2.7–3.6 V vs. 1.5–1.95 V), temperature grade (E vs. I), and AC timing specs. Substituting the 23K640-E/P into a 1.8 V design risks overvoltage damage, and its higher VCC minimum prevents operation in low-voltage battery systems intended for the 23A640-I/P.