The RDA1845/1845D is a single-chip transceiver for Walkie Talkie with fully integrated synthesizer, IF selectivity and base-band signal processing. The transceiver uses the CMOS process, support digital volume control and require the least external component. The package size is 6X6mm and is completely adjustment-free.

 

The RDA1845/1845D has a powerful low-IF digital audio processor, this make it have optimum sound quality with varying reception conditions.

 

The RDA1845/1845D can be tuned to the worldwide frequency band for Walkie Talkie.

 

Features

1. CMOS single-chip fully-integrated transceiver

2. Support worldwide frequency band：
       ♦ 300Mhz-500 MHz
       ♦ 12.5Khz,25Khz channels

3. Digital low-IF tuner：
       ♦ Image-reject down-converter
       ♦ High performance A/D converter
       ♦ IF selectivity performed internally

4. Fully integrated digital frequency synthesizer：
       ♦ fully integrated on-chip RF and IF VCO
       ♦ fully integrated on-chip loop filter

5. Auto DC offset calibration

6. Digital auto frequency control (AFC)

7. Digital auto gain control (AGC)

8. Support multi-reference clocks：
       ♦ 12.8/25.6Mhz
       ♦ 13/26Mhz

9. Selectable pre/de-emphasis

10.Support CTCSS and CDCSS

11.Receive signal strength indicator (RSSI)

12.Provide programmable VOX and Squelch indicator

13.Analog and digital volume control

14.Reference clock drift compensation

15.3-wire serial control bus interface

16.Directly support 32Ω resistance loading

17.Integrated LDO regulator：
        ♦ 2.7 to 3.3 V operation voltage

18.6X6mm 40 pin QFN package

 

Applications

1.Cellular handsets
2.Family radio services
3.Walkie Talkies