User's Manual
Table Of Contents
- Document History
- Introduction
- Product Concept
- Application Interface
- Operating Modes
- Power Supply
- Power Up / Power Down Scenarios
- Automatic GPRS Multislot Class Change
- Charging Control
- Summary of State Transitions (Except SLEEP Mode)
- RTC Backup
- SIM Interface
- Serial Interface ASC0
- Serial Interface ASC1
- USB Interface
- I2C Interface
- Audio Interfaces
- Control Signals
- Antenna Interface
- Electrical, Reliability and Radio Characteristics
- Mechanics
- Sample Application
- Reference Approval
- Appendix
TC63 Hardware Interface Description
Strictly confidential / Draft
s
TC63_HD_V00.432 Page 25 of 97 11.05.2005
Example: If the length of the flex cable reaches the maximum length of 100mm, this
connection may cause, for example, a resistance of 30m in the BATT+ line and
30m in the GND line. As a result, a 2A transmit burst would add up to a total
voltage drop of 120mV. Plus, if a battery pack is involved, further losses may
occur due to the resistance across the battery lines and the internal resistance of
the battery including its protection circuit.
Figure 3: Power supply limits during transmit burst
3.2.2 Measuring the Supply Voltage V
BATT+
The reference points for measuring the supply voltage V
BATT+
on the module are BATT+ and
GND, both accessible at a capacitor located close to the board-to-board connector of the
module.
Figure 4: Position of the reference points BATT+ and GND
3.2.3 Monitoring Power Supply by AT Command
To monitor the supply voltage you can also use the AT^SBV command which returns the
value related to the reference points BATT+ and GND.
The module continuously measures the voltage at intervals depending on the operating
mode of the RF interface. The duration of measuring ranges from 0.5s in TALK/DATA mode
to 50s when TC63 is in IDLE mode or Limited Service (deregistered). The displayed voltage
(in mV) is averaged over the last measuring period before the AT^SBV command was
executed.
Transmit
burst 2A
Transmit
burst 2A
Ripple
Drop
min. 3.2V
BATT+
Reference
point
BATT+
Reference
point GND