STMicroelectronics STM1404CSNJQ6F

Overview

STM1404CSNJQ6F from STMicroelectronics is a FIPS-140 Level 4 security supervisor IC designed for cryptographic module protection in POS terminals and secure embedded systems. It provides four high-impedance physical tamper inputs (TP1–TP4), over/under voltage detection (2.0 V / 4.2 V thresholds), factory-programmable over/under temperature monitoring (–25°C to +95°C range), automatic battery switchover with Vccsw status indicator, and open-drain security alarm (SAL) output. Its primary role is intrusion detection and supply integrity enforcement during cryptographic operation.

For engineers reviewing the STM1404CSNJQ6F datasheet, STM1404CSNJQ6F pinout, STM1404CSNJQ6F application, or STM1404CSNJQ6F equivalent, key selection considerations include tamper input configuration (NH/NL), VOUT behavior under SAL assertion (grounded in STM1404C variant), battery switchover threshold (~2.4 V), low quiescent current (5.3 µA typ), and QFN16 3×3 mm RoHS-compliant packaging.

Technical Context

The STM1404C implements a dual-mode tamper detection architecture: TP1/TP3 are normally high (NH) inputs tied externally to VOUT/VTPU via high-impedance resistors, triggering on pull-down; TP2/TP4 are normally low (NL), tied to VSS, triggering on pull-up. Voltage monitoring compares VCC or VBAT against fixed 2.0 V (undervoltage) and 4.2 V (overvoltage) thresholds, while temperature thresholds (TL/TH) are factory-programmed per customer specification.

Upon tamper or fault detection, the SAL output asserts active-low and forces VOUT to ground - a critical feature enabling direct SRAM VCC shorting to erase volatile cryptographic keys. The Vccsw pin transitions high during battery backup and remains high during SAL assertion, serving as both BATT ON and tamper-active indicator. All critical outputs (SAL, RST, PFO, BLD) are open-drain with no internal pull-ups.

Key Specifications

Pinout & Package

STM1404CSNJQ6F is housed in a secure, low-profile 16-pin QFN package (3 mm × 3 mm body, 0.5 mm pitch) with exposed thermal pad. Pin 1 is marked by a dot; pin numbering follows standard counter-clockwise convention from top-left corner.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar security supervisor applications.

Compared with MAX1363EUB+ and DS1832S+, STM1404CSNJQ6F uniquely delivers FIPS-140 Level 4 compliance through four configurable tamper inputs, factory-programmable temperature limits, and VOUT-to-ground action on alarm - essential for EMVCo, ZKA, and PED-certified designs.

Availability

STM1404CSNJQ6F is available at Aetrix Electronics and suitable for POS terminal security modules, EMVCo-certified payment devices, and ZKA-compliant banking hardware requiring stable component supply and long-term lifecycle assurance.

Supply support for STM1404CSNJQ6F 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, specializing in secure microcontrollers, power management, and analog/mixed-signal ICs for industrial, automotive, and secure computing markets.

The STM1404 family belongs to ST's security supervisor product line, engineered specifically to meet FIPS-140 Level 4 and EMVCo physical tamper requirements in cryptographic modules - with emphasis on low-power battery operation and deterministic key-erasure behavior.

FAQ

What is the function of the VTPU pin on STM1404CSNJQ6F?

VTPU (Pin 9) supplies bias voltage to TP1 and TP3 tamper inputs, switching between VCC and VBAT depending on the active supply rail. Unlike STM1404A's VREF, it provides no precision reference - its sole purpose is to enable NH tamper detection logic. It must not be loaded beyond 10 µA to avoid affecting tamper threshold accuracy.

How does STM1404CSNJQ6F differ from STM1404A and STM1404B in VOUT behavior?

STM1404C drives VOUT to ground when SAL is asserted, enabling direct SRAM VCC shorting for cryptographic key erasure. STM1404A holds VOUT ON (VCC or VBAT), while STM1404B places VOUT in high-impedance state. This distinction is critical for compliance with EMVCo and ZKA zero-retention requirements - only STM1404C guarantees immediate power removal from secure memory.

Can the temperature trip points be modified after manufacturing?

No. Lower (TL) and upper (TH) temperature thresholds are factory-programmed during final test and permanently stored in one-time-programmable (OTP) memory. They cannot be altered in the field or via software. Selection of –25°C/–35°C for TL and +80°C/+85°C/+95°C for TH must be specified at order time using the full part number suffix (e.g., SNJQ6F denotes specific TL/TH configuration).

What is the recommended external circuit for TP2/TP4 (NL) tamper inputs?

TP2 and TP4 require a 10 MΩ pull-down resistor to VSS and connection to a normally open (NO) switch or conductive foil loop. Tamper is detected when the pin voltage rises above 1.2 V due to switch closure or foil short. The resistor must be shielded from ESD and conductive contaminants; layout should minimize trace length and avoid routing near noisy signals to prevent false triggers.