Texas Instruments CC2400RSU

Overview

CC2400RSU from Texas Instruments (formerly Chipcon) is a true single-chip 2.4 GHz RF transceiver with integrated baseband modem, supporting 10 kbps, 250 kbps, and 1 Mbps over-the-air data rates, −87 dBm sensitivity at 1 Mbps (BER=10⁻³), and 24 mA RX current consumption. It operates in the 2.4–2.4835 GHz ISM band and targets low-power wireless audio, PC peripherals, and game controllers.

For engineers reviewing the CC2400RSU datasheet, CC2400RSU pinout, CC2400RSU application, or CC2400RSU equivalent, key selection considerations include its QFN-48 package, SPI-configurable I/Q low-IF receiver and direct up-conversion transmitter, programmable output power across 8 steps, digital RSSI output, and hardware-accelerated packet handling with 32-byte FIFO.

Technical Context

The CC2400RSU implements an agile frequency synthesizer with 40 µs PLL lock time and ±500 kHz AFC range, enabling rapid channel switching and robust frequency stability in noisy environments. Its I/Q low-IF receiver uses a 1 MHz intermediate frequency and digitally programmable channel filters (125–1000 kHz), while the I/Q direct up-conversion transmitter supports GFSK/FSK modulation with ±250 kHz deviation at 1 Mbps.

Baseband processing is offloaded via dedicated hardware: preamble generation, sync word detection, CRC computation over data fields, 8B/10B line coding option, and burst transmission support. Configuration occurs via a 4-wire SPI interface with up to 20 MHz clock, operating across dual supply domains-1.6–2.0 V core (AVDD/DVDD1.8) and 1.6–3.6 V I/O (DVDD3.3).

Key Specifications

Pinout & Package

CC2400RSU is housed in a 7×7 mm QFN-48 package with exposed die attach pad (AGND) requiring solid ground plane connection. Pin functions are validated per SWRS042A Rev. A, Page 13–14.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar 2.4 GHz RF transceiver applications.

Compared with CC2400RSU, CC2500 offers superior sensitivity and extended packet features in identical packaging, while nRF24L01+ trades configurability for integration and ease-of-use-making CC2400RSU optimal for designs requiring full hardware control, regulatory flexibility, and balanced power/performance trade-offs.

Availability

CC2400RSU is available at Aetrix Electronics and suitable for wireless audio accessories, game controllers, and sports equipment requiring stable component supply and long-term industrial availability.

Supply support for CC2400RSU 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

Texas Instruments acquired Chipcon in 2006 and maintains legacy support for SmartRF® transceivers. TI is a global semiconductor leader focused on analog and embedded processing technologies.

The CC2400RSU belongs to the SmartRF®-03 family, designed specifically for cost-sensitive, low-power 2.4 GHz ISM band applications where high integration, regulatory compliance, and SPI-based configurability are essential.

FAQ

What is the maximum over-the-air data rate supported by the CC2400RSU?

The CC2400RSU supports three fixed over-the-air data rates: 10 kbps, 250 kbps, and 1 Mbps. These rates are selected via configuration registers and require no hardware modification. At 1 Mbps, the device achieves −87 dBm sensitivity (BER=10⁻³) with ±250 kHz FSK deviation and 1 MHz channel bandwidth. The CC2400RSU does not support variable or interpolated data rates outside this set.

Does the CC2400RSU require external RF filters or matching components?

No, the CC2400RSU does not require external RF filters. Its integrated RF front-end-including on-chip LNA, PA, and I/Q architecture-provides >56 dB image rejection and meets EN 300 440, FCC Part 15, and ARIB STD-T66 spurious emission limits. Only a balun and matching network (per SWRS042A Page 50) are needed between RF_P/RF_N and the antenna; no SAW or ceramic filters are necessary for compliance.

What power supply configurations are required for proper operation of the CC2400RSU?

The CC2400RSU requires two independent supply rails: a 1.6–2.0 V core supply (AVDD/DVDD1.8) for analog/digital core logic, and a 1.6–3.6 V I/O supply (DVDD3.3) for digital interfaces. The core supply must remain active when DVDD3.3 is applied to prevent internal latch-up. Recommended values are 1.8 V core and either 1.8 V or 3.3 V I/O, depending on host MCU voltage levels. Decoupling capacitors per SWRS042A Page 17 are mandatory.

How is the CC2400RSU configured during system startup?

The CC2400RSU is configured exclusively via its 4-wire SPI interface (SCLK, SI, SO, CSn), with register writes performed after power-up and crystal stabilization (~1.13 ms). Configuration includes frequency channel, data rate, output power, packet format, and AFC settings. TI's SmartRF Studio software generates complete initialization sequences. No boot ROM or internal nonvolatile memory exists-the CC2400RSU relies entirely on host MCU-driven SPI writes before RF operation.

What is the function of the TXRX_SWITCH pin on the CC2400RSU?

The TXRX_SWITCH pin on the CC2400RSU serves as the common analog supply node for the RF front-end switch matrix. It must be DC-coupled externally to both RF_P and RF_N pins through low-impedance paths to enable proper transmit/receive path isolation. This pin is not a control signal-it is a power rail that ensures consistent biasing of internal transmit/receive switches and prevents cross-talk. Incorrect routing violates RF performance specs and may cause desense or spectral regrowth.