MICRF102 Micrel MICRF102 QwikRadio UHF ASK Transmitter General Description The MICRF102 is a single chip Transmitter IC for remote wireless applications. The device employs Micrels latest Qwi- kRadio technology. This device is a true data-in, antenna- out monolithic device. All antenna tuning is accomplished QwikRadio automatically within the IC which eliminates manual tuning, Features and reduces production costs. The result is a highly reliable Complete UHF transmitter on a monolithic chip yet extremely low cost solution for high volume wireless Frequency range 300MHz to 470MHz applications. Because the MICRF102 is a true single-chip Data rates to 20kbps radio transmitter, it is easy to apply, minimizing design and Automatic antenna alignment, no manual adjustment production costs, and improving time to market. Low external part count The MICRF102 uses a novel architecture where the external Low standby current <0.04A loop antenna is tuned to the internal output stage. This trans- Applications mitter is designed to comply with worldwide UHF unlicensed Remote Keyless Entry systems (RKE) band intentional radiator regulations. The IC is compatible with Remote fan/light control virtually all ASK/OOK (Amplitude Shift Keying/On-Off Keyed) Garage door opener transmitters UHF receiver types from wide-band super-regenerative radios Remote sensor data links to narrow-band, high performance super-heterodyne receiv- Tire Pressure Monitoring System (TPMS) ers. The transmitter is designed to work with transmitter data Telemetry rates from 100 to 20k bits per second. The automatic tuning, in conjunction with the external resistor, ensures that the transmitter output power stays constant for the life of the battery. When used with Micrels family of QwikRadio receivers, the MICRF102 provides the lowest cost and most reliable remote actuator and RF link system available. Data sheets and support documentation can be found on Micrels web site at: www.micrel.com. Ordering Information Part Number Temperature Package Range Standard Pb-Free MICRF102BM MICRF102YM -40C to +85C 8-Pin SOIC Typical Application +5V 4.7F C2 ASK DATA INPUT 8.2pF 50V (4.7pF 50V) RP1 MICRF102 100k 0.1F PC ASK RP2 VDD ANTP C3 PCB Antenna 6.8k 12pF 50V L1 VSS ANTN (2.7pF 50V) REFOSC STBY Y1 100k +5V QwikRadio is a trademark of Micrel, Inc. The QwikRadio ICs were developed under a partnership agreement with AIT of Orlando, Florida Micrel, Inc. 2180 Fortune Drive San Jose, CA 95131 USA tel + 1 (408) 944-0800 fax + 1 (408) 474-1000 MICRF102 Micrel Pin Con guration PC 1 8 ASK VDD 2 7 ANTP VSS 3 6 ANTN REFOSC 4 5 STBY 8-Pin SOIC (M) Pin Description Pin Number Pin Name Pin Function 1 PC Power Control Input. The voltage at this pin should be set between 0.15V to 0.35V for normal operation. 2 VDD Positive power supply input for the IC. This pin requires a large capacitor for ripple decoupling. A 4.7F is recommended. 3 VSS This pin is the ground return for the IC. A power supply bypass capacitor connected from V to V should have the shortest possible path. DD SS 4 REFOSC This is the timing reference frequency which is the transmit frequency di- vided by 32. Connect a crystal (mode dependent) between this pin and V , SS or drive the input with an AC-coupled 0.5V input clock. See Reference PP Oscillator section in this data sheet. The crystal needs to have a 10pF load capacitance. 5 STBY Input for transmitter stand by control pin is pulled to V for transmit opera- DD tion and V for stand-by mode. The device requires 0.0 volts to be placed SS in stand by. 6 ANTN Negative RF power output to drive the low side of the transmit loop antenna. The RF output stage is tuned in the data transitions in the ASK pin. 7 ANTP Positive RF power output to drive the high side of the transmit loop antenna. The RF output stage is tuned in the data transitions in the ASK pin. 8 ASK Amplitude Shift Key modulation data input pin. For CW operation, connect this pin to V . Several transitions of highs and lows are required to tune the DD output RF stages. MICRF102 2 December 2006