CoolPAM
Average current & Talk time
Avago Technologies’CoolPAM is stage-bypass PA technol- Average current consumed by PA can be calculated by
ogy which saves more power compared with convention- summing up current at each output power weighted with
al PA. With this technology, the ACPM-7392 has very low
quiescent current, and efficiencies at low and medium
output power ranges are high.
probability. So it is expressed with integration of multipli-
cation of current and probability at each output power.
Incorporation of bias circuit
Talk time is extended more as average current consump-
tion is lowered.
The ACPM-7392 has internal bias circuit, which removes
the need for external constant voltage source (LDO). PA
on/off is controlled by Ven. This is digitally control pin.
Mode control pins
Vmode and Vbp are digitally controlled by baseband and
they control the operating mode of the PA. The operating
logic table is summarized on the page 2. These pins do not
require constant voltage for interface. .
3-mode power control with two mode control pins
The ACPM-7392 supports three power modes ( bypass
power mode/mid power mode/high power mode) with
two mode control pins (Vmode and Vbp). This control
scheme enables the ACPM-7392 to save power consump-
tion more, which accordingly gives extended talk time.
UMTS PA performance comparison
– CoolPAM 4 and CoolPAM 5
PDF (probability density function) showing distribution
of output power of mobile in real field gives motivation
for stage-bypass PA. Output power is less than 16dBm for
most of operating time (during talking), so it is important
to save power consumption at low and medium output
power ranges.
450
400
CP5
350
300
250
200
150
100
50
CP4
PDF and Current
0
-10
0
10
20
30
Pout(dBm)
70
60
50
40
30
20
10
0
CP5
CP4
-10 -8
-6
-4
-2
0
2
4
6
8
10 12 14 16
Pout(dBm)
Icc Comparison of CP5 to CP4 (Avago CoolPAM)
The 5th generation of CoolPAM technology, ACPM-7392
can dramatically reduce Icc down to 3mA at bypass mode,
which improves overall talk time and battery usage time
of handset more compared with the CP4.
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