DP480 Service Manual
9
4.6.Power Section
The radio applies 7.4V lithium-ion battery for power supply. RF power amplification and audio power
amplification are directly powered by battery; the battery outputs 3.6V to supply power to PMU in AT1846S
and HS8861 through DC-DC switch; 3M, 3C and USB3.3V output from PMU separately supplies power to
other baseband circuits; the battery outputs 5V voltage through LDO and then outputs separate 5T and 5R
after control by Q100 and Q102.
RF PA: RF Power Amplifier Circuit Q500 (RD07MUS2B), Q501 (RD01MUS2)
Audio PA: Audio Power Amplifier Circuit U3 (TDA8547TS)
3M: EEPROM IC200 (AT24C512C)
3C: Transistor X500 (12.8M TCXO)
5T: RF Pre-drive Amplifier Circuit Q502 (2SC5108), Q503 (2SC3356)
DC-DC: PMU IC1 (HS8861), U500 (RDA1846S)
4.7.IC Description
4.7.1.Features of AT1846S
a. Integrated CMOS RF front-end
b. High linearity low-noise amplifier and mixer
c. Low IF receiver path
⚫ Automatic DC offset calibration circuit
⚫ High performance analogue/digital converter and digital/analogue converter
⚫ Fully-integrated receiver filter
To Next Page
Loading...
Need help?
General
