ATA5823 ATMEL Corporation, ATA5823 Datasheet - Page 23

• Manufacturer Part Number: ATA5823
• Description: Uhf Ask/fsk Transceiver Ata5823 Ata5824
• Manufacturer: ATMEL Corporation

7.14
4829D–RKE–06/06
Output Power and TX Supply Current versus Supply Voltage and Temperature
Table 7-8
the 433.92 MHz and 6.2 dBm case versus temperature and supply voltage measured according
to
the receiver sensitivity the supply voltage has here the major impact on output power variations
because of the large signal behavior of a power amplifier. Thus a 5V system using the internal
voltage regulator shows much less variation than a 2.15V to 3.6V battery system because the
AVCC supply voltage is 3.25V ±0.25V for a 5V system.
The reason is that the amplitude at the output RF_OUT with optimum load resistance is
AVCC
changed. This means that the theoretical output power reduction if reducing the supply voltage
from 3.0V to 2.15V is 10 log ((3V
ple behavior in the measurements. This is not the same case for higher voltages, since here,
increasing the supply voltage from 3V to 3.6V should theoretical increase the power by 1.8 dB,
but only 0.9 dB in the measurements shows that the amplitude does not increase with the supply
voltage because the load impedance is optimized for 3V and the output amplitude stays more
constant because of the current source nature of the output.
.
Table 7-8.
Table 7-9
3.0V/25°C. As can be seen, a temperature change to
power by less than 1 dB due to the band-gap regulated output current. Measurements of all the
cases in
relative behavior as shown in
Table 7-9.
Figure 7-12 on page 22
V
V
T
T
T
T
T
T
amb
amb
S
S
–
amb
amb
amb
amb
= V
= V
0.4V and the power is proportional to (AVCC
Table 7-7 on page 22
= +105°C
= +105°C
shows the measurement of the output power for a typical device with V
= –40°C
= +25°C
= –40°C
= +25°C
shows the relative changes of the output power of a typical device compared to
S1
S1
= V
= V
Measurements of Typical Output Power Relative to 3 V/25°C
Measured Output Power and Supply Current at 433.92 MHz, PWR_H = GND
S2
S2
with components according to
Table
overtemperature and supply voltage have shown about the same
9.25 mA
3.2 dBm
10.2 mA
3.4 dBm
10.9 mA
3.0 dBm
–3.0 dB
–2.8 dB
–3.2 dB
–
2.15V
2.15V
0.4V)
7-9.
2
/(2.15V
–
0.4V)
–
10.19 mA
11.19 mA
12.02 mA
40°C as well as to +105°C reduces the
2
5.5 dBm
6.2 dBm
5.4 dBm
–0.7 dB
–0.8 dB
–
) = 3.4 dB.
3.0V
Table 7-7 on page
3.0V
0 dB
0.4V)
ATA5823/ATA5824
2
if the load impedance is not
Table 7-8
22. As opposed to
shows that princi-
10.78 mA
11.79 mA
12.73 mA
6.2 dBm
7.1 dBm
6.3 dBm
S1
+0.9 dB
+0.1 dB
3.6V
3.6V
0 dB
= V
S2
= V
S
23
in