Infineon Technologies CY7C63231A-SXC

Overview

CY7C63231A-SXC from Cypress Semiconductor is a low-speed USB peripheral controller with integrated 8-bit RISC microcontroller, USB transceiver, and PS/2 mode auto-detection. It operates at 12 MHz CPU clock, includes 3 KB EPROM and 96 bytes RAM, supports one control + one data endpoint, and delivers 50 mA sink per GPIO pin. Used in HID devices such as optical mice and gamepads requiring dual-mode interface without external switching components.

For engineers reviewing the CY7C63231A-SXC datasheet, CY7C63231A-SXC pinout, CY7C63231A-SXC application, or CY7C63231A-SXC equivalent, key selection criteria include its internal oscillator elimination of external crystal, 3.3 V regulated USB pull-up output, PS/2/USB auto-configuration capability, GPIO interrupt masking, and suspend-mode wake-up timer with no external components.

Technical Context

This device implements a Harvard-architecture RISC core with dedicated USB Serial Interface Engine (SIE) handling token, data, and handshake phases per USB 2.0 low-speed specification. It integrates a 3.3 V regulator for D+ pull-up, supports automatic mode detection between USB and PS/2 via bus signaling, and uses internal oscillator or 6 MHz ceramic resonator for clocking.

The controller provides full USB HID 1.1 compliance with endpoint 0 (control) and endpoint 1 (data), configurable GPIO ports (up to 10 pins), maskable edge-triggered interrupts on all I/O, and a 12-bit free-running timer. Suspend mode enables ultra-low-power operation with periodic wake-up using internal timer-no external RC network required.

Key Specifications

Pinout & Package

Package: 18-pin SOIC (Small Outline Integrated Circuit), body width 3.9 mm, lead pitch 0.050 inch (1.27 mm).

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar low-speed USB peripheral controller applications.

Compared with CY7C63231A-SXC, the PDIP variant offers mechanical robustness and hand-solderability, while the CY7C63221A-SXC provides backward hardware compatibility with field-deployed designs-both retain full USB/PS/2 auto-detection, internal regulator, and GPIO interrupt features.

Availability

CY7C63231A-SXC is available at Aetrix Electronics and suitable for optical mouse, gamepad controller, and industrial keypad applications requiring stable component supply, long-term manufacturability, and dual-interface flexibility.

Supply support for CY7C63231A-SXC 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

Cypress Semiconductor (now part of Infineon Technologies) is a fabless semiconductor company specializing in programmable system-on-chip (PSoC), USB controllers, and mixed-signal solutions for embedded interfaces.

The enCoRe™ USB product line was designed specifically for cost-sensitive, space-constrained HID peripherals requiring seamless USB and PS/2 interoperability without external mode-selection circuitry.

FAQ

Does CY7C63231A-SXC require an external crystal to operate?

No. The device includes an internal oscillator that supports full USB/PS/2 operation without any external timing components. A 6 MHz ceramic resonator may be used optionally for improved frequency accuracy, but it is not required for basic functionality or USB enumeration.

Can CY7C63231A-SXC be used in USB-only applications without PS/2 support?

Yes. Although it supports automatic PS/2/USB mode detection, the device can be configured exclusively for USB operation via firmware initialization. PS/2 functionality remains inactive unless explicitly enabled and detected on the bus, making it fully suitable for USB-only HID endpoints.

What is the maximum current drive capability per GPIO pin?

Each GPIO pin supports up to 50 mA sink current. This allows direct driving of LEDs, small relays, or logic-level inputs without external buffer transistors-critical for minimizing BOM in compact HID designs.

How does suspend mode wake-up work without external components?

The internal 12-bit free-running timer generates periodic wake-up events during USB suspend. Its clock source remains active in suspend, and the timer overflow triggers a wake-up interrupt-no external RC network or crystal is needed for this low-power timing function.