Description
The U3741BM 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 (1 kBaud to 3.2 kBaud for FSK) in Manchester or Bi-phase code. The receiver is well suited to operate with Atmels PLL RF transmitter U2741B. Its main applications are in the areas of telemetering, security technology and keyless-entry systems. It can be used in the frequency receiving range of f0 = 300 MHz to 450 MHz for ASK or FSK data transmission. All the state ments made below refer to 433.92-MHz and 315-MHz applications.

FEATUREs
• 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
• Supply Voltage 4.5 V to 5.5 V
• Operating Temperature Range -40°C to 105°C
• Single-ended RF Input for Easy Adaptation to λ/4 Antenna or Printed Antenna on PCB
• Low-cost Solution Due to High Integration Level
• ESD Protection According to MIL-STD 883 (4KV HBM) Except Pin POUT (2KV HBM)
• High Image Frequency Suppression due to 1 MHz IF in Conjunction with a SAW Front-end 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
• 2 Different IF Bandwidth Versions are Available (300 kHz and 600 kHz)