User Manual
Table Of Contents
- 1. Introduction
- 2. GR47/GR48 Radio Devices
- 3. Abbreviations
- 4. Mechanical Description
- 5. System Connector Interface
- 5.1 Overview
- 5.2 General Electrical and Logical Characteristics
- 5.3 Grounds
- 5.4 VCC - Regulated Power Supply Input
- 5.5 Battery Charging Input (CHG_IN)
- 5.6 Turning the Radio Device ON/OFF and the External Power Signal
- 5.7 Analogue Audio
- 5.8 PCM Digital Audio
- 5.9 Serial Data Interfaces
- 5.10 SIM Card Related Signals
- 5.11 Service/Programming
- 5.12 Buzzer
- 5.13 LED
- 5.14 General Purpose Digital I/O Ports
- 5.15 Extended I/O capabilities
- 5.16 General Purpose Analogue I/O Ports
- 5.17 External I 2C Serial Control Bus
- 5.18 TX_ON - Burst Transmission
- 5.19 Real Time Clock
- 6. Antenna Connector
- 7. Keyboard Interface
- 8. Hints for Integrating the Radio Device
- 9. Embedded Applications
- 10. TCP/IP Stack
- 11. Technical Data
- 12. Declaration of Conformity
- 13. Introduction to the Developer’s Kit
- 14. Using the Developer’s Kit
5. SYSTEM CONNECTOR INTERFACE
27
LZT 123 7589 R1A
Turning the Radio Device Off
Figure 5.3 Off timings and VIO performance
(2) It is a requirement from most GSM network providers that GSM products
properly detach from the network during a power-down sequence. In
order to achieve this it is important that the VCC supply is not removed or
turned off before VIO has been deactivated by the module.
ON/OFF
VIO
t
SPD
t
OFF
t
PULSE
t
SCSD
VCC
(Performs GSM Network detach
and SIM power management)
Software controlled
shutdown.
Symbol Parameters Conditions Min. Typ Max Unit
t
63'
Time for software
pulse detection
which initiates a
software
shutdown
800 - - ms
t
38/6(
Application ON/
OFF pulse width
1000 - - ms
t
6&6'
Software
controlled
shutdown
deactivates VIO
(2)
-
)
2.5
)
10
(3)
s
)
t
2))
Time when VCC
power supply can
be disabled
VIO is
DISABLED
0 - - ms