Microchip Technology 23K256-I/P

Overview

23K256-I/P from Microchip Technology Inc. is a 256 Kbit (32,768 × 8-bit) low-power SPI Serial SRAM with 32-byte page architecture, 20 MHz max clock frequency, and industrial temperature range (–40°C to +85°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 arbitration in embedded microcontroller systems.

For engineers reviewing the 23K256-I/P datasheet, 23K256-I/P pinout, 23K256-I/P application, or 23K256-I/P equivalent, this device serves as a drop-in serial memory upgrade for PIC® MCU-based data logging, real-time configuration storage, and firmware parameter buffering where SPI interface simplicity and low quiescent power are critical.

Technical Context

The 23K256-I/P implements a standard SPI-compatible 4-wire serial interface (CS, SCK, SI, SO) with dedicated HOLD input for pausing ongoing transfers without reset or reinitialization. Its internal 16-bit address pointer supports byte, page (32-byte), and sequential read/write modes via STATUS register configuration.

It features CMOS-compatible I/O thresholds (VIH ≥ 0.7×VCC, VIL ≤ 0.2×VCC), 7 pF input capacitance, and guaranteed AC timing down to 25 ns setup/hold for CS and clock signals at 3.0 V and +85°C - enabling reliable operation in noise-sensitive industrial control and automotive body electronics environments.

Key Specifications

Pinout & Package

23K256-I/P is supplied 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 (–40°C to +85°C).

Key Features

Applications

Equivalent & Alternatives

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

Compared with 23K256-I/SN and 23LC256-I/P, the 23K256-I/P offers through-hole mechanical robustness for lab validation and legacy systems, while maintaining identical electrical performance and firmware compatibility across all three variants.

Availability

23K256-I/P is available at Aetrix Electronics and suitable for industrial data loggers, automotive body control modules, and medical point-of-care monitors requiring stable component supply and long-term lifecycle support.

Supply support for 23K256-I/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 23K256 belongs to Microchip's serial SRAM product line, designed specifically to provide low-power, SPI-compatible memory expansion for resource-constrained microcontroller systems in industrial and automotive environments.

FAQ

What is the maximum operating clock frequency of the 23K256-I/P?

The 23K256-I/P supports a maximum clock frequency of 20 MHz at VCC = 3.0 V and TA = +85°C. At lower voltages or higher temperatures, the maximum allowable frequency decreases per Table 1-2 in the DS22100F datasheet - e.g., 16 MHz at 3.0 V and +125°C (automotive grade), or 10 MHz at 1.5 V (23A256 variant). The 23K256-I/P is rated for industrial temperature only, so 20 MHz applies strictly within –40°C to +85°C.

Does the 23K256-I/P require external pull-up resistors on its SPI lines?

No, the 23K256-I/P does not require external pull-up resistors on SI, SO, or SCK lines - all are actively driven CMOS inputs/outputs with defined VIH/VIL thresholds. However, CS and HOLD lines should be pulled high via 10 kΩ resistors in systems where those signals may float during reset or power-up to ensure predictable standby and hold-disable states. This prevents unintended activation that could disrupt SPI bus sharing.

How does the HOLD function interact with the STATUS register in the 23K256-I/P?

The HOLD function in the 23K256-I/P is disabled unless bit 0 (HOLD Enable) in the STATUS register is cleared to '0'. When set to '1', the HOLD pin is ignored regardless of its logic level. This allows firmware to dynamically disable the feature during critical sequences. Once enabled (bit 0 = 0), pulling HOLD low pauses ongoing SPI transfers - SI, SCK, and SO enter high-impedance, and the internal address pointer freezes - resuming automatically when HOLD returns high while SCK is low.

Can the 23K256-I/P retain data during brief power interruptions?

Yes, the 23K256-I/P guarantees data retention down to VCC = 1.2 V (per Parameter D011 in DS22100F), meaning it maintains stored contents during brown-out conditions typical of capacitor-backed 3.3 V rails. This enables graceful shutdown handling in systems with backup capacitors - e.g., retaining last-known sensor values or configuration flags until main power recovers or nonvolatile storage (EEPROM/Flash) can be updated.

What package variants share the same pinout and electrical characteristics as the 23K256-I/P?

The 23K256-I/SN (SOIC-8) and 23K256-I/ST (TSSOP-8) share identical pinout, signal definitions, timing, and DC specifications with the 23K256-I/P. All three packages use the same 8-pin configuration (CS, SO, VSS, SI, SCK, HOLD, VCC), same VCC range (2.7–3.6 V), and same industrial temperature rating. Mechanical differences (body size, lead pitch, mounting method) are the only distinctions - making them functionally interchangeable in firmware and schematic design.