DSSS low power radio transceiver The STD-504 is a 2.4 GHz transceiver enclosed in a small compact shield casing designed for industrial applications. The transceiver uses Direct Sequence Spread Spectrum (DSSS) modulation and true diversity circuit, enabling reliable communications even in the congested 2.4 GHz band. The STD-504 complies with the European EN 300 328, U.S FCC Part 15.247, Canadian ISED RSS-210 and Japanese ARIB STD-T66 standard, making it ready for the global market. The transceiver uses a transparent data interface to enable users to communicate using their own protocols. The module's configuration can be set easily via the UART interface using dedicated commands. Features ■ CE, FCC, ISED and ARIB complient ■ Uses direct sequence spread spectrum (DSSS) modulation ■ Channel stepping option controlled via CHC pin ■ A true diversity receiver (two built-in receiver circuits) ■ Module settings using dedicated commands ■ Data communication using a transparent interface ■ Onboard temperature sensor General Parameter Applicable standard Communication method Emission type Frequency Channel spacing RF chip rate Supply voltage Supply current RF output power Receiver sensitivity Operating temperature Specification EN 300 328 / FCC Part 15.247 / ISED RSS-210 / ARIB STD-T66 Simplex, Half duplex F1D (FSK) Interface Parameter Specification Data interface (DI / DO / CLK) 19,200 bps (Synchronous) Command interface (TXD / RXD) UART 19,200 / 38,400 / 57,600 bps Data Length: 8 bit, Parity: None, Stop Bit: 2, Flow control: None Specifications are subject to change without prior notice CIRSRII DESIGN, INC. https://www.circuitdesign.jp STD-504 2.4 GHz ver.1.0 Jan 2026 Sales Division 7557-1 Hotaka, Azumino, Nagano 399-8303, Japan Tel:+81-(0)263-82-1024 Fax:+81-(0)263-82-1016