SX1238 WIRELESS, SENSING & TIMING DATASHEET SX1238 - Fully Integrated Transceiver with +27dBm TX Power VDD2 RXEN MODE RX RFI VBAT1&2 VR ANA VR DIG RC Power Distribution System Oscillator LNA Single to Mixers Differential RESET PREAMP SPI ANT RXTX RSSI AFC IND Division by PA0 2,4, or 6 PA DIO0 Tank DIO1 Inductor DIO2 DIO3 Loop Frac-N PLL Filter Synthesizer DIO4 Ramp & DIO5 Control XO 32 MHz VDD1 PAout PDET TXEN XTAL GND TX RFO VR PA Frequency Synthesis Transmitter Blocks Primary Analog Preamp/PA Receive Blocks Control Blocks Primary Digital GENERAL DESCRIPTION KEY PRODUCT FEATURES +27 dBm - 500 mW RF output power The SX1238 is a fully integrated ISM band transceiver optimized for use in the (FCC Part 15) 915 MHz band in the +27 dBm high efficiency PA US and 868 MHz band in Europe with a minimum of Programmable bit rate up to 300kbps external components. It offers a combination of high link budget and low current consumption in all operating modes. High sensitivity: -124 dBm at 1.2 kbps The 150 dB link budget is achieved by a low noise CMOS 863 - 870 MHz and 902 - 928 MHz receiver front end and up to +27 dBm of transmit output power. This is made possible by a fully integrated front end 80 dB blocking Immunity consisting of a TR Switch, LNA and efficient PA. This makes Low current, 100nA register retention SX1238 ideal for applications requiring extended range, high link budget, or operation in the presence of high Fully integrated synthesizer with a resolution of 61 Hz interference. FSK, GFSK, MSK, GMSK and OOK modulations The Low-IF architecture of the SX1238 sees fast transceiver Built-in bit synchronizer performing clock recovery start times and demodulation predicated towards low Sync word recognition modulation index and Gaussian filtered spectrally efficient modulation formats. Preamble detection 115 dB+ dynamic range RSSI Automatic RF sense with ultra-fast AFC APPLICATIONS Packet engine up to 64 bytes with CRC Automated Meter Reading Built-in temperature sensor and low battery indicator Wireless Sensor Networks ORDERING INFORMATION Home and Building Automation Wireless Alarm and Security Systems Part Number Delivery MOQ / Multiple Industrial Monitoring and Control SX1238IMLTRT Tape & Reel 3000 pieces MLPQ 40 Package - Operating Range -40 +85C Pb-free, Halogen free, RoHS/WEEE compliant product SX1238 Rev.2, June 2014 Page 1 www.semtech.com 2014 Semtech Corp. Interpolation & Decimation & Filltering Filtering Demodulator & Bit Modulator Synchronizer Packet Engine & 66 byte FIFO Control Registers - Shift Registers - SPI InterfaceSX1238 High Power Transceiver IC WIRELESS, SENSING & TIMING DATASHEET Table of contents Section Page 1. General Description ................................................................................................................................................ 6 1.1. Simplified Block Diagram ................................................................................................................................ 6 1.2. Pin and Marking Diagram .................................................................................................................................7 1.3. Pin Description .................................................................................................................................................8 2. Electrical Characteristics....................................................................................................................................... 10 2.1. ESD Notice.................................................................................................................................................... 10 2.2. Absolute Maximum Ratings .......................................................................................................................... 10 2.3. Operating Range........................................................................................................................................... 10 2.4. Chip Specification ...........................................................................................................................................11 2.4.1. Power Consumption............................................................................................................................... 11 2.4.2. Frequency Synthesis.............................................................................................................................. 11 2.4.3. Receiver................................................................................................................................................. 12 2.4.4. Transmitter............................................................................................................................................. 13 2.4.5. Front End Control.................................................................................................................................. 14 2.4.6. Digital Specification................................................................................................................................ 15 3. Chip Description.................................................................................................................................................... 16 3.1. Power Supply Strategy.................................................................................................................................. 17 3.2. Low Battery Detector..................................................................................................................................... 17 3.3. Frequency Synthesis..................................................................................................................................... 17 3.3.1. Reference Oscillator............................................................................................................................... 17 3.3.2. CLKOUT Output ......................................................................................................................................18 3.3.3. PLL Architecture..................................................................................................................................... 18 3.3.4. RC Oscillator.......................................................................................................................................... 20 3.4. Transmitter Description .....................................................................................................................................21 3.4.1. Architecture Description......................................................................................................................... 21 3.4.2. Bit Rate Setting ...................................................................................................................................... 21 3.4.3. FSK Modulation...................................................................................................................................... 22 3.4.4. OOK Modulation..................................................................................................................................... 23 3.4.5. Modulation Shaping ............................................................................................................................... 23 3.4.6. RF Power Amplifiers .............................................................................................................................. 23 3.5. Receiver Description .........................................................................................................................................24 3.5.1. Overview................................................................................................................................................ 24 3.5.2. LNA1, LNA2 ........................................................................................................................................... 24 3.5.3. Automatic Gain Control - AGC............................................................................................................... 24 3.5.4. RSSI ........................................................................................................................................................26 3.5.5. Channel Filter......................................................................................................................................... 26 3.5.6. FSK Demodulator................................................................................................................................... 27 3.5.7. OOK Demodulator.................................................................................................................................. 27 3.5.8. Bit Synchronizer ......................................................................................................................................30 3.5.9. Frequency Error Indicator ...................................................................................................................... 30 3.5.10. AFC........................................................................................................................................................ 31 3.5.11. Preamble Detector ................................................................................................................................. 32 SX1238 Rev.2, June 2014 Page 2 www.semtech.com 2014 Semtech Corp.