Download GM862-PCS Hardware User Guide

Telit GM862-PCS/-GPRS/-GSM
Hardware User guide
1vv0300613, Rev. ISSUE#4, - 10/02/04
Contents
1
OVERVIEW
4
2
HARDWARE COMMANDS
5
2.1
Turning ON the GM862-GPRS
5
2.2
Turning OFF the GM862-GPRS
2.2.1.1 Hardware shutdown
2.2.1.2 Hardware Unconditional shutdown
7
7
7
3
POWER SUPPLY
9
3.1
Power Supply Requirements
9
3.2
General Design Rules
3.2.1
Electrical design Guidelines
3.2.1.1 + 5V input Source Power Supply Design Guidelines
3.2.1.2 + 12V input Source Power Supply Design Guidelines
3.2.1.3 Battery Source Power Supply Design Guidelines
3.2.1.4 Battery Charge control Circuitry Design Guidelines
3.2.2
Thermal Design Guidelines
3.2.3
Power Supply PCB layout Guidelines
9
10
10
11
12
12
14
15
4
17
SERIAL PORT
4.1
RS232 level translation
19
4.2
5V UART level translation
21
5
MICROPHONE
23
5.1
Microphone line Characteristic and requirements
23
5.2
General Design Rules
26
5.3
Microphone Biasing
5.3.1
Balanced Microphone biasing
5.3.2
Unbalanced Microphone biasing
26
27
28
5.4
Microphone buffering
5.4.1
Buffered Balanced Mic.
5.4.2
Buffered Unbalanced (Single Ended) Mic.
29
29
31
Reproduction forbidden without DAI Telecom written authorization – All Right reserved – Right of modification reserved
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