Huawei Y511-U030 Repair Manual page 58

XXXX The basic version Repair Manual

Circuit analysis:
The transmitting circuit is composed of chip (U600) MT6166, RF power amplifier (U1, U703,
U708), filter circuit (U616, U607) antenna and matching network circuit.
Working mode control signal GPCTRL0, GPCTRL1, GPCTRL2, RF_RAMP control of the
RF power amplifier from baseband chip.
The control logic:

Fault analysis and treatment process:
Such as playing no phone, no signal, the signal is weak, first confirm the antenna feed point
contact with the motherboard, no stolen goods. Then check the working voltage of U1 is normal,
such as matching network device schematic diagram has no bad, weld short-circuit phenomenon,
after eliminating the adverse change welding according to the main chip U101, transceiver chip
U600, U1, U713, U708 amplifier. The other RF connector J700, bad J701 can cause RF bad,
need to consider when repair.
The following chart repair process:
2013-09-25
V1.0
华为机密，未经许可不得扩散
internal public
第 58 页，共 79 页