U3745BM

• Operating Temperature Range -40°C to +85°C
• Minimal External Circuitry Requirements, No RF Components on the PC Board Except Matching to the Receiver Antenna
• High Sensitivity, Especially at Low Data Rates
• Sensitivity Reduction Possible Even While Receiving
• Fully Integrated VCO
• Low Power Consumption Due to Configurable Self Polling with a Programmable Time Frame Check
• Single-ended RF Input for Easy Matching to
/4 Antenna or Printed Antenna on PCB
• Low-cost Solution Due to High Integration Level
• ESD Protection According to MIL-STD 883 (4 KV HBM) Except Pin POUT (2 KV HBM)
• High Image Frequency Suppression Due to 1 MHz IF in Conjunction with a SAW Frontend Filter. Up to 40 dB is Thereby Achievable with Newer SAWs
• Programmable Output Port for Sensitivity Selection or for Controlling External Periphery
• Communication to the Microcontroller Possible via a Single, Bi-directional Data Line
• Power Management (Polling) is also Possible by Means of a Separate Pin via the Microcontroller

The U3745BM is a multi-chip PLL receiver device supplied in an SO20 package. It has been specially developed for the demands of RF low-cost data transmission systems with low data rates from 1 kBaud to 10 kBaud in Manchester or Bi-phase code. The receiver is well suited to operate with Atmel's PLL RF transmitter U2745B. U3745BM can be used in the frequency receiving range of f₀ = 310 MHz to 440 MHz for ASK data transmission. All the statements made below refer to 433.92-MHz and 315-MHz applications.

The main applications of the U3745BM are in the areas of outside temperature metering, socket control, garage door opener, consumption metering, light/fan or aircondition control, jalousies, wireless keyboard and various other consumer market applications.