Power Supply Process; Data Transmission And Process; Power Management - HYT TC-610 Service Manual

3.

Data Transmission and Process

EEPROM data initiation
Programming data transmission
Encode process of Channel Selector knob
Signalling encode and decode
Data transmission of baseband processor (PLL)

Power Supply Process

Diagram for the Circuit
7.2V
601s
L604
After the radio is powered on, the battery voltage is provided to the RF power amplifier and audio power
amplifier, to meet the requirements of sufficient power amplification after filtered by L604 and C682.
Another path is input with the 5V regulator (U606) and outputs VCC_5V voltage for use by MCU and the
baseband processor after regulated. Because the radio works in half duplex mode, it is required to
control the Tx and Rx power supply alternately. To meet the requirement of the battery save mode, MCU
should output a pulse signal with fixed duty factor (control signal of SAVE). When the SAVE signal of
MCU is of high level, Q610 is on and provides a 5V voltage (V_SAVE) for the operating circuit. PLL and
the receive circuit operate. When the SAVE signal is a pulse signal, the radio enters the battery save
mode. When transmitting, TXC, control signal of CPU, is of high level. Q611 is on and provides a 5V
voltage (TX_VCC) for the transmit circuit. The transmit circuit operates.
Power supplies of the Tx section and Rx section both have symmetrical regulation measures. When the
load change changes the output voltage/current, the regulator closed-loop feedback circuit operates,
regulating the output voltage at 5V.
5V
U606
Vin Vout
SW

power management

V-TX
FMMT717
Q611
TXC
Figure 10
18
TC-610/620 Service Manual
POWER-SAVE
FMMT717
Q610
Q612
UPA572T
SAVE