STMicroelectronics STTS2002B2DN3F

Overview

STTS2002B2DN3F from STMicroelectronics is a JEDEC TSE2002a2-compliant memory module temperature sensor with integrated 2 Kb SPD EEPROM, designed for DDR3/DDR4 DIMMs in laptops and servers. It delivers programmable 9–12-bit temperature resolution (0.25 °C/LSB default), ±1 °C accuracy from +75 °C to +95 °C, and operates from 2.3 V to 3.6 V in a 2 mm × 3 mm TDFN8 package.

For engineers reviewing the STTS2002B2DN3F datasheet, STTS2002B2DN3F pinout, STTS2002B2DN3F application, or STTS2002B2DN3F equivalent, this device supports SMBus/I²C up to 400 kHz, provides open-drain EVENT output for thermal alarm signaling, integrates write-protected SPD EEPROM for DRAM configuration storage, and enables per-module thermal monitoring without external components.

Technical Context

The STTS2002B2DN3F implements a sigma-delta ADC for direct ambient temperature digitization and stores calibrated °C values in a read-only temperature register. Its dual-address architecture uses separate I²C DTI codes ('0011' for TS, '1010' for EEPROM) to isolate sensor and memory access on the same bus.

It supports programmable hysteresis (0/1.5/3/6 °C), comparator or interrupt mode on the EVENT pin, and configurable trip points (alarm window, critical threshold). The 2 Kb SPD EEPROM (256 × 8 bits) features permanent/reversible software write protection for the upper 128 bytes (00h–7Fh), matching JEDEC SPD requirements for DRAM modules.

Key Specifications

Pinout & Package

STTS2002B2DN3F uses an 8-lead TDFN package (2 mm × 3 mm, max height 0.80 mm), JEDEC MO-229 WCED-3 compliant, RoHS and halogen-free.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar memory module thermal sensing and SPD storage applications.

Compared with AT24C02D-SSHM-T and MAX6602AESA+, the STTS2002B2DN3F uniquely combines JEDEC-compliant thermal sensing and SPD EEPROM in one TDFN8 package, enabling single-component DIMM integration while meeting both JEDEC TSE2002a2 and SPD specification requirements.

Availability

STTS2002B2DN3F is available at Aetrix Electronics and suitable for laptop DDR4 thermal management, server RDIMM SPD integration, and industrial embedded memory modules requiring stable component supply across extended product lifecycles.

Supply support for STTS2002B2DN3F 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, delivering automotive, industrial, and power management solutions with emphasis on reliability and system-level integration.

The STTS2002 series belongs to ST's memory interface and thermal management product line, engineered specifically to consolidate SPD EEPROM and JEDEC-compliant temperature sensing into a single compact package for DDR memory modules.

FAQ

What is the factory-default temperature resolution setting?

The STTS2002B2DN3F powers up with 10-bit resolution enabled by default, yielding 0.25 °C per LSB. This value is stored in the Temperature Resolution Register (TRES) and can be changed via I²C write to addresses 0x0E–0x0F. No external calibration is required, as the ADC is factory-trimmed for offset and gain across the full −40 °C to +125 °C range.

How does the EVENT pin behave in comparator versus interrupt mode?

In comparator mode, EVENT asserts low when temperature crosses the upper or lower alarm boundary and remains low until it returns within the hysteresis band. In interrupt mode, EVENT pulses low for 100 ms upon threshold crossing and requires software clearing of the status bit in the Configuration Register to reset. Both modes use the same trip point registers but differ in latching behavior and host software handling.

Can the SPD EEPROM be fully write-protected, including the lower 128 bytes?

Yes - the lower 128 bytes (80h–FFh) support two software write protection mechanisms: reversible (via SWP/CWP commands) and permanent (via PSWP command). Once PSWP is set, the entire array becomes read-only until power cycle, but the upper 128 bytes retain permanent lock capability independent of PSWP state. Protection status is verified by reading the Capability Register bit 4.

Is SMBus timeout supported, and what are its timing limits?

Yes - the STTS2002B2DN3F supports configurable SMBus timeout from 25 ms to 35 ms, controlled via the SMBus Timeout Register (address 0x0D). This prevents bus lock-up during communication errors and aligns with SMBus 2.0 specification requirements. Timeout recovery is automatic: the device resets its internal state and releases SDA after timeout expiration, allowing the master to reinitialize the transaction.