Infineon Technologies CYPD3173-24LQXQ

Overview

CYPD3173-24LQXQ from Infineon Technologies (formerly Cypress) is a USB Type-C port controller with integrated NFET gate driver, designed for secondary-side feedback control in AC/DC power adapters. It supports USB PD 3.0 PPS, QC4+, and legacy charging protocols, delivers independent constant voltage (3.3–21 V) and constant current (1–3 A) regulation, and integrates BMC transceiver, LSCSA, opto-coupler-compatible error amplifiers, and VBUS discharge FETs.

For engineers reviewing the CYPD3173-24LQXQ datasheet, CYPD3173-24LQXQ pinout, CYPD3173-24LQXQ application, or CYPD3173-24LQXQ equivalent, key selection criteria include its dual CV/CC regulation capability, 24-pin QFN package with –40 °C to +105 °C operation, integrated CC1/CC2 BMC PHY, NFET gate drive up to VBUS_IN + 8 V, and support for opto-coupled or direct feedback architectures in USB PD 3.0 PPS adapters.

Technical Context

The device implements two independent error amplifier blocks-one for constant voltage (CV) regulation referenced to 0.744 V and one for constant current (CC) regulation using an integrated low-side current sense amplifier (LSCSA) with gain options from 5 to 150. It supports full USB PD 3.0 Programmable Power Supply (PPS) via BMC-encoded communication on CC1/CC2 pins with built-in Rp termination switching and collision avoidance.

Its MCU subsystem features a Cortex-M0 core with 64 KB Flash and 4 KB SRAM, enabling firmware-updatable protocol stack execution. The high-voltage regulator accepts 3.3–21.5 V input at VBUS_IN and generates internal VDDD (5 V or VBUS_IN − 300 mV) and VCCD (1.8 V), powering analog and digital domains while supporting 6 GPIOs with configurable functions including SWD debug interface on DP_GPIO5/DM_GPIO4.

Key Specifications

Pinout & Package

The CYPD3173-24LQXQ is housed in a 24-pin QFN package (4 mm × 4 mm, 0.5 mm pitch) with exposed thermal pad (EPAD) connected to VSS for enhanced thermal performance in high-power adapter applications.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar USB Type-C port controller applications.

Compared with STUSB4500QTR and MPQ4282GJ-AEC1, CYPD3173-24LQXQ uniquely combines PPS-capable dual-loop regulation, legacy charging detection, and full BMC PHY integration in a single 24-pin QFN-reducing system-level design effort and validation time for consumer power adapters.

Availability

CYPD3173-24LQXQ is available at Aetrix Electronics and suitable for USB PD 3.0 PPS wall adapters, Quick Charge 4.0 travel adapters, and universal laptop chargers requiring stable component supply, long-term lifecycle support, and industrial temperature grade operation.

Supply support for CYPD3173-24LQXQ 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 headquartered in Munich, Germany, specializing in power management, sensing, and connectivity solutions for industrial, automotive, and consumer markets.

CYPD3173-24LQXQ belongs to Infineon's EZ-PD™ CCG3PA product line, engineered specifically for high-efficiency, firmware-upgradable USB Type-C power adapters with integrated secondary-side control and multi-protocol charging support.

FAQ

What is the maximum VBUS_IN voltage supported by CYPD3173-24LQXQ?

The device supports VBUS_IN up to 21.5 V, with its internal high-voltage regulator operating across 3.3 V to 21.5 V input range. At inputs between 5.5 V and 21.5 V, the regulator delivers a stable 5 V to VDDD; below 5.5 V, it outputs VBUS_IN minus 300 mV. This wide input range enables compatibility with diverse flyback and resonant converter topologies used in USB PD adapters.

Does CYPD3173-24LQXQ require external components for USB PD CC line termination?

No external Rp or Rd resistors are required-the device integrates programmable pull-up (Rp) resistors and switches for both CC1 and CC2 lines per USB Type-C specification. An external 390-pF capacitor is mandatory on each CC pin for signal integrity, but all termination logic, collision avoidance, and BMC encoding/decoding are handled internally.

How is constant current regulation implemented without a dedicated current DAC?

CC regulation uses an integrated low-side current sense amplifier (LSCSA) with differential inputs (CSP/CSN), selectable gain (5–150), and active offset cancellation. A 5 mΩ sense resistor yields ~150 mV full-scale at 3 A; the LSCSA output feeds a dedicated CC error amplifier whose reference is trimmed to match USB PD PPS current steps, enabling ±1% accuracy without external DACs.

Can CYPD3173-24LQXQ be programmed in-system after soldering?

Yes-firmware updates can be performed in-system via the CC communication channel using Application Firmware Update (AFU) protocol, eliminating the need for physical SWD access after assembly. For initial programming or recovery, the SWD interface remains accessible through DP_GPIO5 (SWD_CLK) and DM_GPIO4 (SWD_DATA), supporting standard ARM Cortex-M0 debug tools.