Interface Application; Power Interface - Quectel UC20 User Manual

3

Interface Application

This chapter describes the hardware interfaces of UMTS&LTE EVB, shown as follows:


Power interface


USB interface

Audio interface

USIM card interface

UART interface
It also provides information about LEDs, buttons and test points to help you use the UMTS&LTE EVB.
3.1. Power Interface
The power supply of UMTS&LTE EVB could come from the external input which is connected with power
jack or USB receptacle. The power jack and USB receptacle connects a step-down converter which can
provide the supply voltage (VBAT) required for operating EVB and UMTS&LTE module.
Figure 4 shows the simplified power supply schematic, and Figure 5 shows the power interface of
UMTS&LTE EVB.
J801
USB
interface
J201
Power
supply
UMTS&LTE_EVB_User_Guide
S201
AAT2138
Power
Step-down converter
switch
Figure 4: Simplified Power Supply Schematic
U201
Confidential / Released
UMTS/HSPA/LTE Module Series
UMTS&LTE EVB User Guide
1.8V
U302
LDO
3.0V
U303
LDO
J102
Power supply to
VBAT
UMTS&LTE module
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