STMicroelectronics M48T02-200PC1

Overview

M48T02-200PC1 from STMicroelectronics is a 5.0 V, 16 Kbit (2 Kb × 8) non-volatile TIMEKEEPER® SRAM integrating ultra-low-power static RAM, real-time clock, and power-fail control circuitry in a single CAPHAT™ DIP package. It delivers BCD-coded timekeeping (year/month/day/hour/minute/second), ±1 minute/month accuracy at 25 °C, software-controlled clock calibration, and automatic WRITE protection during VCC decay - used in industrial control panels requiring persistent timestamping and battery-backed memory without external backup components.

For engineers reviewing the M48T02-200PC1 datasheet, M48T02-200PC1 pinout, M48T02-200PC1 application, or M48T02-200PC1 equivalent, key selection considerations include its BYTEWIDE™ SRAM interface compatibility with JEDEC 2K×8 SRAMs, integrated 32.768 kHz crystal and lithium battery, VPFD voltage window (4.5 V ≤ VPFD ≤ 4.75 V), BiPORT™ clock register mapping (7F8h–7FFh), and BOK flag-based battery health monitoring.

Technical Context

The M48T02-200PC1 integrates a 2048 × 8 BiPORT™ SRAM array and quartz-controlled oscillator on a single die, with clock registers mapped to upper memory addresses (7F8h–7FFh) for byte-wide access using standard SRAM read/write cycles. Clock updates occur once per second via internal counter logic, independent of host access timing.

Its power-fail detection circuit monitors VCC continuously, initiating automatic chip deselect and WRITE protection when voltage enters the 4.5–4.75 V VPFD window, then switches to lithium battery backup below ~3 V. The BOK (Battery OK) flag indicates battery health upon power-up and blocks first WRITE until cleared.

Key Specifications

Pinout & Package

Package: 24-pin plastic DIP (PCDIP24), 600 mil width, with integrated lithium battery and 32.768 kHz crystal in CAPHAT™ housing.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar non-volatile timekeeping SRAM applications.

Compared with DS1642-120IND+, M48T02-200PC1 reduces BOM count and improves long-term reliability via integrated crystal/battery; versus M48T35Y-100PC1, it prioritizes drop-in JEDEC SRAM compatibility and compact DIP form factor over density and voltage flexibility.

Availability

M48T02-200PC1 is available at Aetrix Electronics and suitable for industrial HMI panels, energy metering systems, medical diagnostic loggers, and factory automation PLCs requiring stable component supply with guaranteed 10-year battery-backed data retention.

Supply support for M48T02-200PC1 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

STMicroelectronics is a global semiconductor leader headquartered in Geneva, Switzerland, designing and manufacturing analog, MCU, power, and memory solutions for industrial, automotive, and consumer markets.

The TIMEKEEPER® product line delivers integrated RTC+SRAM devices optimized for applications demanding long-term, maintenance-free timestamping and data persistence - targeting industrial control, smart metering, and medical instrumentation.

FAQ

What is the function of the BOK (Battery OK) flag?

The BOK flag is a status bit set automatically during power-up if the integrated lithium battery voltage falls below specification. It blocks the first WRITE operation until cleared, preventing corrupted data writes due to insufficient backup power. The flag clears after the first successful WRITE, confirming battery readiness for full retention operation.

How does the M48T02-200PC1 handle leap years and month-end date rollovers?

The device implements automatic calendar correction in hardware: it recognizes 28-, 29- (leap year valid through 2100), 30-, and 31-day months and rolls dates correctly without host intervention. This behavior is fixed in silicon and requires no firmware updates or user configuration to maintain accuracy across century boundaries.

Can the M48T02-200PC1 be used as a direct replacement for standard 2K×8 SRAMs?

Yes - it is pin- and function-compatible with JEDEC-standard 2K×8 SRAMs. All control signals (E, G, W), address (A0–A10), and data (DQ0–DQ7) operate identically. Clock registers reside at fixed upper addresses (7F8h–7FFh) and do not interfere with standard memory access unless explicitly read or written.

What happens during a power failure while a WRITE cycle is in progress?

If VCC drops into the VPFD window mid-WRITE, the device halts the operation and places all outputs in high-impedance state. Only the currently addressed memory location may be corrupted; the remainder of SRAM contents and clock registers remain intact. Data retention resumes seamlessly from battery power once VCC falls below ~3 V.