User's Manual

UM-B-045
DA14580 Range extender v.2 reference application
Company confidential
User manual
Revision 1.1
14-September-2015
CFR0012-00 Rev 1
19 of 60
© 2015 Dialog Semiconductor
Figure 10: Detail from Tx_En to Rx_En signal
Power amplifier
4.4.2
The amplifier circuit is the SKY66111-11
2
from Skyworks. The VBIAS pin is connected to the bias
voltage via resistor R7. The resistor value is adjusted so that the +9.3 dBm output power is achieved
at maximum 16.15 mA current consumption.
There are two Low Pass Filters options for the power amplifier. The first one is at the input of the
Skyworks amplifier and is formed by C6, C7 and L3 and the second is at the output of the Skyworks
amplifier and is formed by L4, L5, C18 and C19. The second LPF is used in the current design.
The power amplifier is supplied from pin VBAT_3V directly.