Analog Devices Inc./Maxim Integrated DS2252T-128-16

Overview

DS2252T-128-16 from Maxim Integrated is an 8051-compatible secure microcontroller module featuring 128kB nonvolatile SRAM, 16MHz crystal speed, and permanently powered real-time clock with 0.01s resolution. It executes encrypted code in-system, supports self-modifying firmware, and delivers crashproof operation for tamper-resistant embedded security applications such as cryptographic key storage and secure boot loaders.

For engineers reviewing the DS2252T-128-16 datasheet, DS2252T-128-16 pinout, DS2252T-128-16 application, or DS2252T-128-16 equivalent, this page provides verified technical context, pin-level circuit roles, memory partitioning behavior, power-fail interrupt timing, and validated alternative options for secure microcontroller selection in high-assurance systems.

Technical Context

The DS2252T-128-16 implements a hardened 8051 core with on-chip 64-bit encryption engine, automatic true random key generation, and hardware-enforced self-destruct via SDI input. Its NV RAM retains data >10 years at room temperature without VCC, backed by internal lithium cell and precision band-gap voltage monitoring.

It features dual power-fail detection thresholds (VPFW = 4.37V typ, VCCMIN = 4.12V typ), early-warning interrupt at 2Bh vector, and seamless switchover to battery backup below VLI. Memory organization excludes off-board program memory for security; partitionable mode is disabled in the 128kB variant per datasheet note.

Key Specifications

Pinout & Package

DS2252T-128-16 uses a 40-pin SIMM package (2.65" × 2.385", 0.100" lead pitch) with gold-plated edge contacts. Pin 2 = VCC (+5V), Pin 39 = GND, Pin 20 = SDI (self-destruct trigger), Pin 17 = RST (active-high, internally pulled down), Pins 35/37 = XTAL1/XTAL2 (32kHz RTC crystal interface).

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar secure microcontroller applications.

Compared with DS2252T-128-16, DS5002FP offers identical architecture but reduced memory and no RTC-requiring external components to match timekeeping and tamper-response capabilities. MAX32550 provides greater computational power and modern peripherals but replaces lithium-backed NV RAM with flash-based security, shifting trust assumptions from physical memory retention to cryptographic key management.

Availability

DS2252T-128-16 is available at Aetrix Electronics and suitable for secure key management systems, hardware root-of-trust modules, smart meter security coprocessors, and EMV payment terminal cores requiring stable component supply and long-term lifecycle support.

Supply support for DS2252T-128-16 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

Maxim Integrated (now part of Analog Devices) designs high-reliability analog and mixed-signal ICs for security, power, and sensing applications.

The DS2252T-128-16 belongs to Maxim's Secure Microcontroller family, engineered specifically for systems requiring physical tamper resistance, encrypted in-system programmability, and decade-long nonvolatile data retention without external power.

FAQ

What is the memory configuration of the DS2252T-128-16?

The DS2252T-128-16 contains 128kB of nonvolatile SRAM configured exclusively for program and/or data storage. Unlike smaller variants, it does not support dynamic partitioning between program and data spaces-this mode is explicitly disabled per datasheet Figure 3 note. All 128kB is accessible via the byte-wide bus, preserving I/O ports for application use, and off-board program memory is prohibited for security reasons.

Does the DS2252T-128-16 include a real-time clock, and how is it powered?

Yes, the DS2252T-128-16 integrates a permanently powered real-time clock with 0.01-second resolution, driven by an onboard 32kHz crystal connected to pins XTAL1 and XTAL2. The RTC operates independently of main VCC using an internal lithium cell, ensuring continuous timekeeping even during complete system power loss-critical for timestamping secure events without external backup.

How does the self-destruct mechanism work on the DS2252T-128-16?

The DS2252T-128-16 implements hardware-enforced self-destruct via the SDI (Self-Destruct Input) pin. Applying a logic high to pin 20 triggers immediate erasure of encryption keys, vector RAM contents, and momentary removal of power from the VCCO rail. The input is deglitched-pulses must exceed 10µs (tSPA) to guarantee activation-and is designed to respond to physical tampering attempts like probe contact or voltage glitching.

What are the power-fail detection thresholds for the DS2252T-128-16?

The DS2252T-128-16 features two precision power-fail thresholds: VPFW (power-fail warning) at 4.37V typical, which generates an interrupt at vector 2Bh while allowing continued operation; and VCCMIN (reset threshold) at 4.12V typical, which forces a hardware reset and disables all chip enables. Both are derived from an internal band-gap reference, ensuring stability across temperature and process variation.

Is the DS2252T-128-16 pin-compatible with other devices in the DS2252T family?

Yes, the DS2252T-128-16 shares identical 40-pin SIMM packaging and pinout with DS2252T-64-16 and DS2252T-128-16# variants, including RoHS-compliant versions. All share identical VCC, GND, RST, SDI, PROG, XTAL1/XTAL2, and I/O port assignments. Functional differences (e.g., memory size, partitioning support) are internal and do not affect board layout or interconnect design.