Analog Devices Inc./Maxim Integrated MAXQ1740-FBX+

Overview

MAXQ1740-FBX+ from Maxim Integrated is a DeepCover® secure microcontroller designed for integration directly into magnetic card reader heads, featuring a 16-bit MAXQ20C RISC CPU, hardware AES encryption engine, true random-number generator, self-destruct input, and triple-track magnetic stripe interface. It operates from 1.7V to 3.6V, includes 16KB flash and 1KB fast-wipe NV SRAM, and targets tamper-resistant ATM/POS terminals.

For engineers reviewing the MAXQ1740-FBX+ datasheet, MAXQ1740-FBX+ pinout, MAXQ1740-FBX+ application, or MAXQ1740-FBX+ equivalent, key selection criteria include tamper-responsive memory zeroization, ISO 7811/7812/7813 magnetic track support, 3µA stop-mode current, 1-Wire debug interface, and 28-pin TQFN-EP package compatibility with secure physical layout requirements.

Technical Context

The MAXQ1740-FBX+ implements a Harvard-architecture MAXQ20C core with 1MIPS/MHz performance, pipelined execution, and orthogonal 16-bit instruction set optimized for C compilation. Its security architecture couples voltage-attack sensors, supply overvoltage detection, and a dedicated self-destruct input to trigger instantaneous zeroization of 128 bytes of AES-working NV SRAM and full wipe of 1KB fast-wipe NV SRAM.

Peripherals are hardened for magnetic card reading: the triple-track interface supports direct connection to 3-track read heads without external signal conditioning; two SPI ports, I²C, USART, and 1-Wire enable secure host communication and in-system programming; dual 16-bit timers and wake-up timer support low-power polling and event timing in battery-powered readers.

Key Specifications

Pinout & Package

MAXQ1740-FBX+ is housed in a 28-pin Thin Quad Flat No-lead Exposed Pad (TQFN-EP) package, RoHS-compliant, with thermal pad for enhanced heat dissipation in compact card-reader enclosures.

Key Features

Applications

Equivalent & Alternatives

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

Compared with MAX32590 and STM32L4A6VG, the MAXQ1740-FBX+ uniquely integrates magnetic stripe interface logic, tamper-triggered hardware memory wipe, and ISO-compliant track decoding - making it the only option certified for direct magstripe head placement in PCI PTS v6 Level 3 devices.

Availability

MAXQ1740-FBX+ is available at Aetrix Electronics and suitable for ATM/POS terminals, physical security access systems, and secure ID badge readers requiring stable component supply, long lifecycle support, and traceable sourcing for regulated deployments.

Supply support for MAXQ1740-FBX+ 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 precision analog, mixed-signal, and secure ICs for industrial, automotive, communications, and computing applications.

The MAXQ1740-FBX+ belongs to the DeepCover® secure microcontroller product line, engineered specifically to embed cryptographic protection and physical tamper resistance directly at the point of magnetic card interaction - enabling PCI PTS and FIPS-compliant payment and access systems.

FAQ

What is the primary security function of the self-destruct input on the MAXQ1740-FBX+?

The self-destruct input (SDIN) on the MAXQ1740-FBX+ is an active-low tamper-detection pin that, when asserted, triggers instantaneous zeroization of the 128-byte AES-working NV SRAM and initiates full erasure of the 1KB fast-wipe NV SRAM before any application firmware can execute. This hardware-enforced response prevents extraction of cryptographic keys or sensitive data during physical intrusion attempts, satisfying PCI PTS v6 Level 3 tamper-resistance requirements.

Does the MAXQ1740-FBX+ support all three magnetic stripe tracks simultaneously?

Yes, the MAXQ1740-FBX+ integrates a dedicated triple-track magnetic stripe interface capable of simultaneous analog acquisition and digitization of Tracks 1, 2, and 3. Its SDI, SDO, and SDCLK pins provide direct connection to standard 3-track read heads, and reference firmware supports ISO 7811, ISO 7812, and ISO 7813 formats - enabling full multi-track parsing without external signal conditioning or timing controllers.

What is the role of the 1-Wire interface on the MAXQ1740-FBX+?

The 1-Wire interface on the MAXQ1740-FBX+ serves as a single-pin debug and programming port for in-circuit flash programming, real-time debugging, and boundary-scan testing. It eliminates the need for dedicated JTAG/SWD headers, reducing PCB footprint and simplifying secure layout - especially critical in tamper-resistant enclosures where test points must be minimized or hidden.

How does the MAXQ1740-FBX+ achieve ultra-low power consumption in stop mode?

The MAXQ1740-FBX+ achieves 3µA stop-mode current by powering down the CPU core, flash memory, and most peripherals while retaining only essential tamper-monitoring circuitry - including the self-destruct input detector, voltage-attack sensors, and minimal clock logic. The device remains responsive to wake events from GPIO pins or serial interface activity, enabling rapid resumption of magnetic card reading with sub-millisecond latency.

Is factory programming of secret keys supported for the MAXQ1740-FBX+?

Yes, Maxim Integrated offers optional factory programming of a unique 64-bit serial number and/or customer-defined secret key(s) into the MAXQ1740-FBX+ during wafer sort or final test. This service ensures cryptographic material is injected in a controlled environment prior to shipment, eliminating risks associated with field provisioning and supporting root-of-trust establishment in certified payment and access systems.