Microchip Technology 23A512-I/ST

Overview

23A512-I/ST from Microchip Technology is a 512-Kbit (64K × 8) low-voltage serial SRAM with SPI/SDI/SQI interface, operating from 1.7V–2.2V across –40°C to +85°C industrial temperature range. It delivers 20 MHz clock rate, 3 mA read current at 5.5V/20 MHz (note: V_CC max 2.2V for this variant), 4 µA standby current at +85°C, and supports byte/page/sequential access modes - used in microcontroller-based data buffering where fast nonvolatile-like write performance and low-power operation are critical.

For engineers reviewing the 23A512-I/ST datasheet, 23A512-I/ST pinout, 23A512-I/ST application, or 23A512-I/ST equivalent, key selection considerations include its 1.7–2.2V supply compatibility, SDI/SQI high-speed interface support, HOLD functionality (disabled in SQI mode), 8-lead SOIC-ST package footprint, and distinction from the 2.5–5.5V 23LC512 family members.

Technical Context

The 23A512-I/ST implements a synchronous serial interface with three configurable operational modes (Byte, Page, Sequential) controlled via a writable MODE register. Its dual- and quad-I/O capability relies on dedicated SIO pins shared with SI/SO/HOLD, requiring explicit EDIO/EQIO command entry and RSTIO exit sequences.

It features zero write time, unlimited read/write endurance, and automatic address incrementing within pages (32-byte boundaries) or across the full 64K address space. The HOLD pin suspends ongoing transfers without resetting internal state - but is disabled when SQI mode is active due to SIO3 pin reassignment.

Key Specifications

Pinout & Package

23A512-I/ST is packaged in an 8-lead SOIC (narrow, 3.90 mm body), JEDEC standard package code ST, with 1.27 mm pitch and surface-mount footprint per Microchip drawing C04-057-SN Rev H.

Key Features

Applications

Equivalent & Alternatives

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

Compared with 23LC512-I/ST and 23A512-I/P, the 23A512-I/ST uniquely enables ultra-low-voltage operation down to 1.7V while retaining full SPI/SDI/SQI feature parity - making it the only choice for energy-harvesting or single-cell Li-ion designs demanding both performance and sub-2V compatibility.

Availability

23A512-I/ST is available at Aetrix Electronics and suitable for industrial data loggers, medical wearable sensor hubs, and automotive body control modules requiring stable component supply, long-term lifecycle assurance, and RoHS-compliant sourcing.

Supply support for 23A512-I/ST 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 leading provider of microcontroller, analog, FPGA, and memory solutions, serving industrial, automotive, consumer, and communications markets with vertically integrated silicon and software tools.

The 23A512 belongs to Microchip's serial SRAM product line, designed specifically to deliver high-speed, low-power, pin-efficient external memory for microcontroller-based systems where parallel bus overhead is prohibitive.

FAQ

What is the maximum clock frequency supported by the 23A512-I/ST?

The 23A512-I/ST supports a maximum clock frequency of 20 MHz under industrial temperature conditions (–40°C to +85°C). At extended temperature (–40°C to +125°C), the maximum clock rate is reduced to 16 MHz. This specification applies to all interface modes - SPI, SDI, and SQI - and is validated per Microchip DS20005155C, Table 1-2.

Does the 23A512-I/ST support Quad SPI (QSPI) mode, and what happens to the HOLD function?

Yes, the 23A512-I/ST supports Serial Quad Interface (SQI) mode via the EQIO command. However, in SQI mode, the HOLD/SIO3 pin is reassigned as SIO3 and the HOLD function is disabled. This is explicitly documented in Section 3.5 and Figure 3-3 of the datasheet - users requiring both SQI throughput and transfer suspension must implement software-level coordination instead.

What is the memory organization and page size of the 23A512-I/ST?

The 23A512-I/ST has a 64K × 8-bit organization totaling 512 Kbits, divided into 2048 pages of 32 bytes each. Page-mode operations automatically increment the internal address counter within the current page boundary, wrapping to the start of the page upon overflow - a behavior confirmed in Section 2.2 and Figure 2-3 of DS20005155C.

Can the 23A512-I/ST retain data during power loss, and what is the minimum retention voltage?

The 23A512-I/ST maintains RAM data integrity down to a minimum V_CC of 1.0 V, as specified in Table 1-1 (Parameter D011, VDR). This retention voltage enables reliable operation during brown-out events or when backed by supercapacitors or small batteries - though sustained operation below 1.7 V is not guaranteed.

Is the 23A512-I/ST pin-compatible with the 23LC512-I/ST?

Yes, the 23A512-I/ST and 23LC512-I/ST share identical 8-lead SOIC-ST packaging, pinout, instruction set, timing specifications, and AC/DC characteristics - differing only in V_CC range (1.7–2.2V vs. 2.5–5.5V). This allows direct PCB substitution when supply voltage constraints permit, as confirmed in the Device Selection Table on page 1 of DS20005155C.