Preliminary
RF2475
Truth Table of Pin-by-Pin Biasing
Pin #
1
28
8
9
12
14
15
16
18
19
22
23
25
Pin
LNA
LNA
LNA
LNA
MXR
TX
VCC DOUBLER IF B
IF A
VCC
TX8
TX8
VCC
TX
MXR
VCC8
RX8
Name
Biased
by VCC
Supply
Mode
VCC19 OUT19 VCC8
RX19
VCC
OUT8 VCC19 LO19
RX8
VCC
TX19
TX19
VCC
VCC
PLL
VCC
LO8
TX8
VCC
RX19
VCC
RX8
VCC
RX19
VCC
TX19
VCC
IF
VCC
IF
VCC
VCC
RX-800
RX-1900
TX-800
L
H
L
L
H
L
H
L
L
L
H
L
L
L
L
H
L
L
L
L
L
H
H
H
H
H
H
L
H
H
L
L
L
L
L
H
L
L
L
L
L
H
L
H
L
TX-1900
L
L
L
H
H
L
L
L = Supply Off
H = Supply On
Power Control Modes
Mode
Pin Name Pin #
Controls the Following Circuit Functions
RX19
LNA VCC19
1
1900MHz LNA Bias
MXR VCC19
12
Mixer RF Amplifier
Mixer LO Driver
RX LO Doubler
Doubler VCC
IF B
16
18
19
8
DC Return for the LO Doubler
DC Return for Mixer
DC Return for Mixer
800MHz LNA Bias
8
IF A
RX8
LNA VCC8
MXR VCC8
25
Mixer RF Amplifier
Mixer LO Driver
IF B
IF A
18
19
22
15
DC Return for Mixer
DC Return for Mixer
800MHz TX LO Buffer
1900MHz TX LO Buffer
TX LO Doubler
TX8
VCC TX8
VCC TX19
TX19
Doubler VCC
16
DC Return for the LO Doubler
NOTES:
There are separate RX/TX LO doublers with a common output.
The DC return path for both the TX and RX doublers is via the PLL VCC which is on in all TX and RX modes.
This allows sharing of the LC load at the doubler output, which saves a significant amount of die area.
Rev A2 010918
8-95
RFMD [ RF MICRO DEVICES ]
