Renesas RD68E-T4-AZ

Overview

RD68E-T4-AZ from Cypress Semiconductor is a 2.4 GHz WirelessUSB™ LP Radio SoC integrating DSSS/GFSK transceiver, SPI interface, Auto Transaction Sequencer (ATS), Power Management Unit (PMU), and 16-byte TX/RX FIFOs in a 40-pin QFN 6 × 6 mm package. It delivers +4 dBm transmit power, –97 dBm receive sensitivity, and supports data rates up to 1 Mbps for low-power wireless peripherals.

For engineers reviewing the RD68E-T4-AZ datasheet, RD68E-T4-AZ pinout, RD68E-T4-AZ application, or RD68E-T4-AZ equivalent, key selection criteria include its 1.8–3.6 V operation, sub-1 µA sleep current, integrated PMU for coin-cell support, and hardware-accelerated ACK handling without MCU intervention.

Technical Context

The RD68E-T4-AZ implements a dual-conversion low-IF 2.4 GHz radio with channel-matched filters for interference robustness and supports nine discrete data modes (GFSK at 1 Mbps; DSSS at 15.6–250 kbps). Its baseband handles SOP/EOP detection, CRC16 generation/checking, and AutoRate™ dynamic rate switching based on RSSI and link quality.

It features a fully autonomous ATS engine that manages crystal startup, mode transitions, packet transmission, ACK wait, and timeout recovery - all without firmware involvement for ≤16-byte packets. The PMU provides configurable VREG output (2.4–2.7 V, up to 15 mA) and programmable low-battery detection with seven voltage thresholds.

Key Specifications

Pinout & Package

RD68E-T4-AZ is housed in a space-saving 40-pin QFN package (6 mm × 6 mm, 0.5 mm pitch) with exposed thermal pad (E-PAD) requiring solder connection to GND for thermal and electrical integrity. Pin 1 is marked by corner tab; NC pins must be tied to GND per datasheet guidance.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar 2.4 GHz radio SoC applications.

Compared with CC2530F256 and nRF24L01+, RD68E-T4-AZ uniquely combines ultra-low sleep current, integrated power management, and autonomous transaction sequencing - reducing both component count and firmware development effort for battery-powered HID and remote control designs.

Availability

RD68E-T4-AZ is available at Aetrix Electronics and suitable for wireless keyboards, remote controls, and gamepads requiring stable component supply, long-term lifecycle support, and consistent parametric performance across production batches.

Supply support for RD68E-T4-AZ 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), memory, and connectivity solutions for industrial, automotive, and consumer markets.

RD68E-T4-AZ belongs to the WirelessUSB™ LP SoC product line, engineered specifically for ultra-low-power, low-latency 2.4 GHz proprietary wireless links in human interface devices and remote control applications.

FAQ

What is the primary function of the RD68E-T4-AZ in a wireless system?

The RD68E-T4-AZ serves as a complete 2.4 GHz radio SoC that handles physical layer transmission and reception, packet framing, CRC16 checking, automatic ACK generation, and power management - enabling direct SPI interfacing with an MCU while offloading real-time radio control tasks. RD68E-T4-AZ integrates all essential RF and baseband functions into a single chip, eliminating the need for discrete transceivers, regulators, or timing components in compact wireless peripherals.

Does the RD68E-T4-AZ support both DSSS and GFSK modulation schemes?

Yes, the RD68E-T4-AZ supports both modulation types: GFSK at 1 Mbps for high-throughput applications and DSSS at multiple rates (15.6–250 kbps) for improved interference immunity and extended range. The choice between them is configured via SPI registers and affects packet structure, sensitivity, and power consumption - GFSK yields higher data rate but lower link budget than DSSS at equivalent output power. RD68E-T4-AZ's AutoRate™ feature can dynamically select between them based on RSSI and correlation metrics.

Can the RD68E-T4-AZ operate from a single 1.8 V supply without external regulation?

Yes, RD68E-T4-AZ operates over a 1.8–3.6 V supply range on the VBAT pin and includes an integrated Power Management Unit (PMU) that regulates internal logic (1.8 V) and optionally supplies external circuitry via VREG. When powered at 1.8 V, the PMU remains functional and supports sleep current below 1 µA - making RD68E-T4-AZ suitable for single-cell alkaline or lithium coin-cell operation without external LDOs or boost converters.

How does the Auto Transaction Sequencer (ATS) in the RD68E-T4-AZ reduce firmware overhead?

The ATS in RD68E-T4-AZ automates the entire packet exchange sequence - including crystal startup, synthesizer settling, transmit initiation, ACK wait, timeout handling, and mode transitions - without MCU intervention for packets ≤16 bytes. This eliminates polling loops and timing-critical state machine code, allowing the host MCU to enter low-power modes between events. RD68E-T4-AZ triggers IRQ upon transaction completion, enabling event-driven firmware architecture with minimal latency and deterministic timing.

Is the RD68E-T4-AZ pin-compatible with earlier WirelessUSB™ devices like CYWUSB6934?

No, RD68E-T4-AZ is not pin-compatible with CYWUSB6934. While it is interoperable at the protocol level with first-generation WirelessUSB™ radios (e.g., CYWUSB69xx), RD68E-T4-AZ uses a 40-pin QFN package with different pin assignments - including dedicated PACTL, XOUT, and VI/O pins absent in CYWUSB6934's 32-pin layout. Hardware redesign is required for migration; however, register mapping and SPI command structure remain largely compatible to ease firmware porting. RD68E-T4-AZ's enhanced feature set necessitates updated layout and decoupling per its datasheet recommendations.