Infineon Technologies CY7C65631-56LTXC

Overview

CY7C65631-56LTXC from Infineon Technologies (formerly Cypress) is a 4-port USB 2.0 hub controller with single transaction translator, 56-pin QFN package, –40 °C to +85 °C industrial temperature grade, and integrated USB transceivers, pull-up/down/termination resistors. It enables low-power, cost-optimized USB expansion in embedded docking stations and monitor hubs requiring bus- or self-powered operation.

For engineers reviewing the CY7C65631-56LTXC datasheet, CY7C65631-56LTXC pinout, CY7C65631-56LTXC application, or CY7C65631-56LTXC equivalent, key selection criteria include TT architecture for mixed-speed device support, SPI-configurable VID/PID/port power settings, integrated passive components reducing BOM count, and automotive/industrial temperature compliance.

Technical Context

The CY7C65631 implements a single transaction translator (TT) shared across all four downstream ports, enabling high-speed upstream communication while translating split transactions to full- or low-speed downstream devices. Its USB Serial Interface Engine (SIE) handles bit stuffing, checksum validation, and token identification independently of hub control logic.

Routing logic dynamically directs traffic either through the TT (for full/low-speed downstream devices on a high-speed hub) or directly through the Hub Repeater (for high-speed downstream devices). The internal 24 MHz crystal PLL generates precise USB timing without external clock synthesis circuitry.

Key Specifications

Pinout & Package

Package: 56-pin QFN (8 mm × 8 mm, 0.5 mm pitch), exposed thermal pad, RoHS-compliant, moisture sensitivity level 3.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar USB 2.0 hub controller applications.

Compared with CY7C65640A-56LTXC, CY7C65631 offers identical functionality with updated lifecycle support; versus UPD720114GA-YEU-A, it trades per-port TT flexibility for lower power, smaller footprint, and reduced component count - optimal for cost- and space-constrained industrial hubs.

Availability

CY7C65631-56LTXC is available at Aetrix Electronics and suitable for standalone USB hubs, monitor-integrated hubs, docking stations, and external storage enclosures requiring stable component supply, industrial temperature operation, and long-term design continuity.

Supply support for CY7C65631-56LTXC 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

Infineon Technologies is a global semiconductor leader delivering power systems, microcontrollers, sensors, and connectivity solutions for automotive, industrial, and IoT applications.

The CY7C65631 belongs to the EZ-USB HX2LP Lite™ family, designed specifically for ultra-low-power, cost-sensitive USB 2.0 hub implementations in space-constrained embedded systems.

FAQ

Does CY7C65631-56LTXC require an external crystal?

Yes, it requires a 24 MHz fundamental-mode crystal connected to XTAL_IN and XTAL_OUT pins. The internal PLL uses this reference to generate all necessary USB clock frequencies (48 MHz, 12 MHz, 6 MHz). No external oscillator or clock source is supported - only crystal-based operation is specified and validated.

Can CY7C65631-56LTXC operate without an external SPI EEPROM?

No - the device relies on external SPI EEPROM for critical configuration including VID/PID/DID, port enablement/removability, power settings, and overcurrent parameters. Without EEPROM, the device fails to enumerate on the USB bus. Default factory values are not stored internally; all configuration is loaded at power-up from SPI flash.

What is the function of PWR#[n] and OVR#[n] pins?

PWR#[n] are active-low port power enable outputs that drive external load switches (e.g., AP2171, TPS2051). OVR#[n] are active-low overcurrent fault inputs from those same switches. Their polarity and filter timing (0–15 ms) are configurable via SPI EEPROM, enabling flexible power architecture design across different switch ICs.

Is CY7C65631-56LTXC pin-compatible with CY7C65621-56LTXC?

No - although both use the same 56-pin QFN package, their pin functions differ significantly. CY7C65621 supports only two downstream ports and reassigns several pins (e.g., DP3/DP4, OVR#[3–4]) as NC or alternate functions. Direct substitution will cause functional failure; board layout must match the specific device's pinout.