rf9958 RF Micro Devices, rf9958 Datasheet - Page 5

• Manufacturer Part Number: rf9958
• Description: Cdma/fm Transmit Modulator, If Agc, And Upconverter
• Manufacturer: RF Micro Devices

Rev B11 010720
Pin
10
11
12
13
14
15
16
17
18
19
20
21
Function
BG OUT
RF OUT
MIX IN-
GND1
GND2
VCC3
VCC4
LO2+
LO2-
DEC
PD1
PD2
Description
Bandgap voltage reference. This voltage, constant over temperature
and supply variation, is used to bias internal circuits. A 1nF external
bypass capacitor is required.
Supply voltage for the AGC and the Bandgap circuitry. A 1nF external
bypass capacitor is required and an additional 0.1 F will be required if
no other low frequency bypass capacitors are nearby. The trace length
between the pin and the bypass capacitors should be minimized. The
ground side of the bypass capacitors should connect immediately to
ground plane.
Same as pin 6.
Power down control for overall circuit. When logic “high” ( V
all circuits are operating; when logic “low” ( 0.5V), all circuits are
turned off. The input impedance of this pin is >10k . A DC voltage less
than or equal to the maximum allowable Vcc may be applied to this pin
when no voltage is applied to the Vcc pins.
Supply for the mixer stage only. The supply for the mixer is separated to
maximize IF to RF isolations and reduce the carrier leakage. A 100pF
external bypass capacitor is required and an additional 0.1 F will be
required if no other low frequency bypass capacitors are nearby. The
trace length between the pin and the bypass capacitors should be min-
imized. The ground side of the bypass capacitors should connect
immediately to ground plane.
Power down control for mixer only. When connected to pin 10 (BG
OUT) the mixer circuits are operating; when connected to ground
( 0.5V), the mixer is turned off but all other circuits are operating. A DC
voltage less than or equal to the maximum allowable Vcc may be
applied to this pin when no voltage is applied to the Vcc pins.
Ground connection for the mixer stage. Keep traces physically short
and connect immediately to ground plane for best performance.
RF output pin. An external shunt inductor to V
matching capacitor are required for 50
Current Mirror decoupling pin. A 1000pF external capacitor is required
to bypass this pin. The ground side of the bypass capacitors should
connect immediately to ground plane.
One half of the balanced mixer LO2 input. In single-ended applications,
the other half of the input, LO2- is AC grounded. This is a 50
ance port. This pin is NOT internally DC blocked. An external blocking
capacitor (100pF recommended) must be provided if the pin is con-
nected to a device with DC present.
One half of the balance mixer LO2 input. In single ended applications,
this pin is AC grounded with a 100pF capacitor.
One half of the 200
This pin is NOT internally DC blocked. An external blocking capacitor
(2200pF recommended) must be provided if the pin is connected to a
device with DC present. If no IF filter is needed this pin may be con-
nected to MOD OUT+ through a DC blocking capacitor. An appropriate
matching network may be needed if an IF filter is used.
balanced impedance input to the mixer stage.
output.
CC
plus a series blocking/
CC
-0.7V),
imped-
Interface Schematic
See pin 19.
MIX IN-
LO2+
V
PD1
PD2
CC4
300
BIAS
BIAS
RF9958
40
100
10 k
1 k
BIAS
BIAS
RF OUT
100
450
40
MIX IN+
LO2-
5-97
5