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
25
LZT 123 7589 R1A
Safety considerations should be taken into account. For example,
monitoring the temperature of the battery. If the temperature of the
battery exceeds its specification limits, battery charging must be stopped
immediately. If the battery temperature continues to rise the application
should be suspended or the battery disconnected.
1RWH When charging Lithium batteries, the battery pack must have an internal
protection circuit in accordance with the manufacturer’s instructions.
5.6 Turning the Radio Device ON/OFF and the External Power Signal
Turning the Radio Device On
Figure 5.2 On timings and VIO performance
ON/OFF pulled
up internally
through 39kΩ
t
ON
t
VIO
t
CTS
t
PULSE
Software running
…
t
PRST
VCC
ON/OFF
VIO
CTS
t
O
Symbol Parameters Conditions Min. Typ Max Unit
t
Reference time
when VCC is
within working
limits
(1)
VCC > 3.2V
ON/OFF = VCC
-- - -
t
21
Time after t0
when the ON/
OFF pulse can
begin
VCC > 3.2V 0 - - ms