User's Guide

UL865 Hardware User Guide
1VV0301050 Rev 2 – 2013-10-09
UL865
Mode
Average (mA)
Mode description
SWITCHED OFF
Module supplied but Switched Off
Switched Off
180 uA
IDLE mode (WCDMA)
AT+CFUN=5
1.8
Disabled TX and RX; DRX7
IDLE mode (GSM/EDGE)
AT+CFUN=1
19
Normal mode: full functionality of the module
AT+CFUN=4
16.5
Disabled TX and RX; module is not registered on the
network
AT+CFUN=5
1.2
Disabled TX and RX; DRX9 (1.3mA in case of DRX5)
Operative mode (WCDMA)
WCDMA Voice
152
WCDMA voice call (TX = 10dBm)
WCDMA HSDPA (0dBm)
187
WCDMA data call (Cat 8, TX = 0dBm)
WCDMA HSDPA (22dBm)
494
WCDMA data call (Cat 8, TX = 24dBm)
Operative mode (EDGE)
EDGE 4TX+1RX
EDGE Sending data mode
GSM 850/900 - G8
495
DCS1800/ PCS1900 – G7
484
Operative mode (GSM)
CSD TX and RX mode
GSM VOICE CALL
GSM 850/900 CSD PL5
220
DCS1800/ PCS1900 CSD PL0
167
GPRS 4TX+1RX
GPRS Sending data mode
GSM 850/900 PL5
580
DCS1800/ PCS1900 PL0
438
The GSM system is made in a way that the RF transmission is not continuous, but it is
packed into bursts at a base frequency of approx. 217 Hz, and the relative current peaks
can be as high as about 2A. Therefore the power supply has to be designed to withstand
these current peaks without big voltage drops; this means that both the electrical design
and the board layout must be designed for this current flow. If the layout of the PCB is
not well designed a strong noise floor is generated on the ground and the supply; this will
reflect on all the audio paths producing an audible annoying noise at approx. 217 Hz; if
the voltage drop during the peak current absorption is too much, then the device may even
shutdown as a consequence of the supply voltage drop.
NOTE:
The electrical design for the Power supply should be made ensuring it will be capable of a
peak current output of at least 2 A.
The UL865-EUx variants are supporting EDGE class 33; the NAx variants support EDGE
class 10.