Semtech SX1211 UHF RF Transceiver

Semtech’s (Nasdaq:SMTC) SX1211 is a UHF radio frequency (RF) transceiver with the industry’s lowest receiver (RX) current consumption (<3mA), significantly increasing battery life in wireless sensor network applications. The SX1211 is optimized for asynchronous sensor network designs in the unlicensed industrial, scientific and medical (ISM) frequency bands (868-870 MHz and 902-928 MHz) where low RX power consumption is critical to battery life as the receiver is constantly waking up to sniff for signals.

The SX1211′s RX current consumption is up to five times lower than competitive solutions, resulting in up to five years in battery life for sensor applications. In addition to a low RX current, the device also features a 64-byte FIFO buffer that enables more power efficient batch data transfers between the transceiver and microcontroller. Transmit power consumption at + 10 dBm is only 25 mA.

With support for both frequency-shift keying (FSK) modulation and on-off keying (OOK) modulation, the SX1211 can be used for both new and legacy sensor network designs. The device supports FSK data rates from 1.56 to 100 kbit/s and OOK data rates up to 32 kbit/s. Receiver sensitivity for FSK modulation is -104 dBm at 25 kbit/s and for OOK is -110 dBm at 2 kbit/s.

The SX1211 operates over a supply voltage range of 2.1V to 3.6V. It meets regulatory standards for both Europe (ETSI EN 300- 220-1) and North America (FCC parts 15.247 and 15.249), for both digital modulation (DTS) and frequency hopping systems. The SX1211 is provided in a 5 x 5 mm TQFN32 RoHS-compliant package.

Key Features of the SX1211

  • Power consumption: 3mA receive and 25mA transmit at 10 dBm output power
  • Programmable RF output power: up to +12.5 dBm
  • FSK reception sensitivity: down to -104 dBm at 25 kbit/s
  • OOK reception sensitivity: down to -110 dBm at 2 kbit/s
  • Bit rates up to 100 kbit/s with NRZ coding
  • 64-byte FIFO for transmit /receive data buffering and transfer via SPI bus
  • Incoming sync word recognition
  • RSSI (Received Signal Strength Indicator) range from noise floor to 0 dBm
  • Packet handling, CRC generation and data whitening
  • Built-in bit-synchronizer for incoming data and clock synchronization and recovery

The SX1211 product (order code: SX1211I084TRT) is available immediately in production quantities and is priced at $1.79 each in 3,000-piece minimum lots. Semtech offers comprehensive design assistance, including field- and factory-based support. Data sheets, volume pricing, and delivery quotes, as well as evaluation kits and samples, are available by contacting

Key applications include security and alarm systems, sub-metering, industrial monitoring and control, building automation and KONNEX(TM) systems.

More info: Semtech »