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AS3900

Data Sheet - Detail ed Description

In differential mode peak is equal to VDD, in single ended mode peak is equal to VDD/2.

Note: It is important to note that the overall emitted power of the PA is mainly defined by the VDD and the impedance of the antenna itself.

The Rout of the PA gives only a minor change to the emitted power.

Figure 26. Power Amplifier

power:

Conditions: VDD= 3V, Differential output mode, 10dBm is the desired output power.

Ω

=

⎟

⎠

⎞

⎜

⎝

⎛

−

=

⎟

⎠

⎞

⎜

⎝

⎛

Δ

−

=

=

=

=

+

+

420

10

2

1

.

0

3

2

10

10

)

(

2

2

2

10

)

(

mW

V

V

P

U

VDD

P

U

R

mW

mW

P

RMS

MATCH

ANT

MATCH

ANT

dBm

P

8.10.6 RSSI

The AS3900 has an integrated received signal strength indication field (RSSI) that can be used by the Master to identify the signal strength to all

rssi field provides a digital value for signal strength between 0µVrms and 150µVrms.

VDD

GND

Rout/2

VDD

GND

Rout/2

RF1OUT

RF2OUT

R

DIFFERENTIAL

+VDD

t

-VDD

GND

SINGLE ENDED

+VDD

t

GND

Û

Û

ANT+MATCH

U/2

U/2