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General Description |
A7169 is a monolithic low-IF architecture CMOS FSK/GFSK TRX for wireless applications in the 315/433/470/868/ 915MHz ISM bands. This device is especially suitable for battery-powered application and the 470MHz ~ 510MHz wireless AMR (Auto Meter Reading) in China and 868.3MHz wireless CTR in Europe. A7169 is one of AMICCOM’s Mini Power Consumption Family in sub 1GHz ISM band product line. A7169 is optimized for very low power consumption (i.e. 434MHz band, 3.2mA @ RX mode). In addition, A7169 can offer a very good link budget with a high efficiency class-E power amplifier up to 20dBm and a high RX sensitivity receiver (-107dBm RX sensitivity @ 100Kbps / FSK / 433.92MHz). Therefore, A7169 is very suitable for battery powered application with a nice LOS (line-of-sight) wireless range. A7169 incorporates a baseband modem with the programmable data rate divider from 2K to 500Kbps. For a battery powered system, A7169 supports fast PLL settling time, Crystal oscillator settling time and on-chip Regulator settling time to reduce average power consumption. The RF synthesizer contains a VCO and a low noise fractional-N PLL. The VCO frequency operates at the wanted radio frequency to cover all RF band. Since A7169 is a low-IF architecture TRX with programmable IFBW (IF Filter Bandwidth, 50KHz/100KHz/150KHz/250KHz/500KHz), the RXLO shall be configured to offset an intermediate frequency (IF) to TXRF regarding to the IFBW setting. A7169’s control registers are accessed via 3-wire or 4-wire SPI interface including TX/RF FIFO, VCO frequency, to chip calibration procedures. Another one, via SPI as well, is the unique Strobe command, A7169 can be controlled from power saving mode (deep sleep, sleep, idle, standby), PLL mode, TX mode and RX mode. In addition to SPI, the digital connections between A7169 and MCU are GIO1 (multi-function GPIO) to indicate A7169’s status so that MCU could use either polling or interrupt for radio control. For packet handling, A7169 supports direct mode and FIFO mode. In direct mode, MCU or Encoder shall deliver the defined packet (preamble + sync word + payload) to GIO1/TXD pin. Then, in RX mode, MCU or Decoder can receive the coming packet (preamble + sync word + payload) in bit sequence from GIO1/RXD pin. In FIFO mode, preamble is self-generated by A7169. User just needs to assign the sync word to this device by ID R/W command via SPI. For payload, the built-in separated 64-bytes TX/RX FIFO are used to be this purpose to let user R/W the wanted payload. User can also enable additional packet features like CRC for error detection, FEC (hamming 7 by 4) for 1-bit data correction per code word, Manchester coding, as well as data whitening for data encryption / decryption. Additional device features such as on-chip regulator, RSSI for clear channel assessment, a thermal sensor, low battery detector, carrier detect, preamble detect, frame sync in FIFO mode, auto-ack and auto-resend, AIF (Auto IF function), AFC (Auto Frequency compensation), Auto calibration (VCO, IF Filter), PLL/CLK Generator, on-chip compensated capacitors of Xtal loading, and WOR (Wake on RX) to support the ability to periodically wake up from sleep mode to RX mode and listen for incoming packets without MCU interaction, can be used to simplify system development and cost. Overall, A7169’s highly integrated features and low current consumption offer a reduced BOM cost for a high performance ISM bands product. All features are integrated in a small QFN 3X3 16 pins package. |