MICRF220 300MHz to 450MHz, 3.3V ASK/OOK Receiver with RSSI and Squelch General Description Features The MICRF220 is a 300MHz to 450MHz super- 110dBm sensitivity at 1kbps with 0.1% BER heterodyne, image-reject, RF receiver with automatic Supports bit rates up to 20kbps at 433.92MHz gain control, ASK/OOK demodulator, analog RSSI 25dB image-reject mixer output, and integrated squelch features. It only requires No IF filter required a crystal and a minimum number of external components to implement. The MICRF220 is ideal for low-cost, low- 60dB analog RSSI output range power, RKE, TPMS, and remote actuation applications. 3.0V to 3.6V supply voltage range The MICRF220 achieves 110dBm sensitivity at a bit 4.3mA supply current at 315MHz rate of 1kbps with 0.1% BER. Four demodulator filter 6.0mA supply current at 434MHz bandwidths are selectable in binary steps from 1625Hz 0.1A supply current in shutdown mode to 13kHz at 433.92MHz, allowing the device to support Data output squelch until valid bits detected bit rates up to 20kbps. The device operates from a supply voltage of 3.0V to 3.6V, and typically consumes 16-pin QSOP package (4.9mm x 6.0mm) 4.3mA of supply current at 315MHz and 6.0mA at 40C to +105C temperature range 433.92MHz. A shutdown mode reduces supply current to 3kV HBM ESD Rating 0.1A typical. The squelch feature decreases the activity on the data output pin until valid bits are detected while maintaining overall receiver sensitivity. Datasheets and support documentation can be found on Micrels website at: www.micrel.com. Typical Application 433.92MHz, 1kbps Operation Micrel Inc. 2180 Fortune Drive San Jose, CA 95131 USA tel +1 (408) 944-0800 fax + 1 (408) 474-1000 Micrel, Inc. MICRF220 Ordering Information Part Number Temperature Range Package MICRF220AYQS 40C to +105C 16-Pin QSOP Pin Configuration MICRF220AYQS Pin Description Pin Pin Pin Function Number Name Reference resonator connection to the Pierce oscillator. May also be driven by external reference signal of 1 RO1 200mVp-p to 1.5V p-p amplitude maximum. Internal capacitance of 7pF to GND during normal operation. 2 GNDRF Ground connection for ANT RF input. Connect to PCB ground plane. Antenna Input: RF Signal Input from Antenna. Internally AC coupled. It is recommended to use a matching 3 ANT network with an inductor-to-RF ground to improve ESD protection. 4 GNDRF Ground connection for ANT RF input. Connect to PCB ground plane. Positive supply connection for all chip functions. Bypass with 0.1F capacitor located as close to the VDD pin 5 VDD as possible. Squelch Control Logic-Level Input. An internal pull-up (5A typical) pulls the logic-input HIGH when the device 6 SQ is enabled. A logic LOW on SQ squelches, or reduces, the random activity on DO pin when there is no RF input signal. Demodulator Filter Bandwidth Select Logic-Level Input. This pin has an internal pull-up (3A typical) when the 7 SEL0 chip is on. Use in conjunction with SEL1 to control demodulation bandwidth. Shutdown Control Logic-Level Input. A logic-level LOW enables the device. A logic-level HIGH places the 8 SHDN device in low-power shutdown mode. An internal pull-up (5A typical) pulls the logic input HIGH. 9 GND Ground connection for all chip functions except for RF input. Connect to PCB ground plane. Data Output. Demodulated data output. A current limited CMOS output during normal operation, 25k pull- 10 DO down is present when device is in shutdown. Demodulator Filter Bandwidth Select Logic-Level Input. This pin has an internal pull-up (3A typical) when the 11 SEL1 chip is on. Use in conjunction with SEL0 to Demodulation bandwidth. Demodulation Threshold Voltage Integration Capacitor. Connect a 0.1F capacitor from CTH pin-to-GND to 12 CTH provide a stable slicing threshold. AGC Filter Capacitor. Connect a capacitor from this pin to GND. Refer to the AGC Loop and CAGC section for 13 CAGC information on the capacitor value. Received Signal Strength Indicator. The voltage on this pin is an inversed amplified version of the voltage on 14 RSSI CAGC. Output is from a switched capacitor integrating op amp with 250 typical output impedance. 15 NC No Connect. Leave this pin floating. Reference resonator connection to the Pierce oscillator. Internal capacitance of 7pF to GND during normal 16 RO2 operation. Revision 2.0 August 19, 2015 2