Specifications

Wireless CPU
®
Q24 Series
Interfaces
Electrical characteristics
Signal MIN NOM MAX
VBATT 3.2 V 3.6 V 4.5 V *
VDD 3.1 V 4.5 V
*Max operating Voltage Standing Wave Ratio (VSWR) 2:1.
3.2.2 Power Supply Recommendation
The VBATT voltage limits must be considered at any time.
The worst condition is during the burst period transmission, when current
consumption is at its highest. During this period, the VBATT voltage is minimum:
• The output voltage of the power supply drops.
• Voltage drop is present between the power supply output and the Wireless
CPU
®
supply pins (VBATT).
To ensure a good design, make sure that
during a transmit burst period, the total
drop in voltage should not set the Wireless CPU
®
supply voltage (VBATT) below
VBATT
MIN
= 3.2V.
Notes:
• During a transmit burst, Wireless CPU
®
nominal current is 1.4A only.
• To design the Wireless CPU
®
power supply with a margin, a target of 2A is
recommended.
Caution:
®
•
+ PCB) should be < 150mΩ to limit voltage
•
the following table. "Maximum voltage ripple (Uripp) vs
• If VBATT<3.2V, the Wireless CPU
automatically powers OFF.
When a Wireless CPU
®
is supplied with a battery, the total impedance
(battery + contacts + protections
drop-out within emission burst.
As the radio power amplifier is directly connected to the VBATT, the Wireless
CPU
®
Q24 Series are sensitive to any voltage variation. When a DC/DC
converter is used, Wavecom recommends to set the converter frequency in
such a way that the resulting voltage does not exceed these values, which
are given in
Frequency".
©Confidential Page: 22 / 83
This document is the sole and exclusive property of WAVECOM. Not to be distributed or divulged without
prior written agreement.
WM_PGM_Q24NG_PTS_001-005 November 20, 2007