ATA5811-PLQW Atmel, ATA5811-PLQW Datasheet - Page 19

• Manufacturer Part Number: ATA5811-PLQW
• Description: RF Transceiver RF DATA CONTROL Transceiver
• Manufacturer: Atmel

Specifications of ATA5811-PLQW

• Operating Supply Voltage: 2.5 V, 3.3 V, 5 V
• Mounting Style: SMD/SMT
• Package / Case: QFN-48 EP
• Minimum Operating Temperature: - 40 C
• Operating Temperature (min): -40C
• Operating Temperature (max): 105C
• Operating Temperature Classification: Industrial
• Product Depth (mm): 7mm
• Product Height (mm): 0.9mm
• Product Length (mm): 7mm
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant

4689F–RKE–08/06
Example:
According to
11 dBm the overall current consumption is typically 17.8 mA hence the PA needs
17.8 mA - 6.95 mA = 10.85 mA in this mode which corresponds to an overall power amplifier
efficiency of the PA of (10
Using a higher resistor in this example of R
rent in the PA of 10.85 mA/1.091 = 9.95 mA and 10
using a new load resistance of 300
1 1 d B m
6.95 mA + 9.95 mA = 16.9 mA.
The values of
quality factors Q according to
with the quality factor of Q
lent resistance of the inductor R
10 log (1 + R
the PA efficiency is then 42% instead of 38.6%.
Be aware that the high power mode (PWR_H = AVCC) can only be used with a supply voltage
higher than 2.7V, whereas the low power mode (PWR_H = GND) can be used down to 2.4V as
can be seen in the section
The supply blocking capacitor C
because of the RF current flowing through it.
Figure 5-10. Power Setting and Output Matching
–
0 . 3 8 d B = 1 0 . 6 d B m
Lopt
Table 5-7 on page 20
Table 5-7 on page
/R
loss
) which is equal to 0.32 dB losses in this inductor. Taking this into account
(11dBm/10)
L1
“Electrical Characteristics: General” on page
RF
= 43 the loss in this inductor is estimated with the parallel equiva-
Table 5-7 on page
OUT
C
3
2
20, with a frequency of 433.92 MHz and output power of
were measured with standard multi-layer chip inductors with
(10 nF) has to be placed close to the matching network
VPWR_H
1 mW)/(3V 10.85 mA) 100% = 38.6% in this case.
loss
a n d
AVCC
C
= 2
1
R
1.091 = 327 . The resulting output power is then
L
1
1
1
= 1.091
t h e
10
8
9
20. Looking to the 433.92 MHz/11 dBm case
C
2
o v e r a l l
f
ATA5811/ATA5812
RF_OUT
R_PWR
PWR_H
log(1.091) = 0.38 dB less output power if
L
22 k = 24 k results in 9.1% less cur-
ATA5811/ATA5812
Q
L1
c u r r e n t
and the matching loss with
63.
c o n s u m p t i o n
i s
19