Clock Circuit; Figure 9-11 19.2 Mhz Circuit Block Diagram 1; Table 9-2 Description Of The Signals In The Circuit Diagram In This Section - Huawei U8815 Maintenance Manual

U8815
Maintenance Manual

Table 9-2 Description of the signals in the circuit diagram in this section

Signal
VEXT_DC
VCHG
I2C_SCL_DCDC
I2C_SDA_DCDC The control signal of the charging chip
VPH_PWR
BAT_FET_N
VBAT
USB_HS_DP
USB_HS_DN

9.2.3 Clock Circuit


The following figures show the clock circuit block diagrams.

Figure 9-11 19.2 MHz circuit block diagram 1

Issue 1.0 (2012-02-13)
Description
Charging current to the charger.
Charging the current to the charging
chip through the USB port.
The control signal of the charging chip
Main power supply, supplying power to
the power unit of the main chip
The control signal of the metal-oxide
semiconductor (MOS) (Q201)
Battery voltage
Positive electrode input of USB
differential data bus
Negative electrode input of USB
differential data bus
Circuit block diagram
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9 Principles and Failure Analysis
Reference Measurement
or Wave Form
0-5 V
None
None
Voltage range: 0–4.2 V
Battery voltage, range:
0–4.2 V
None
None
30