LT5515
6
5515fa
GND (Pins 1, 4): Ground Pin.
RF
+
, RF
–
(Pins 2, 3): Differential RF Input Pins. These
pins are internally biased to 1.54V. They must be driven
with a differential signal. An external matching network is
required for impedance transformation.
V
CC
(Pins 5, 8, 9, 12): Power Supply Pins. These pins
should be decoupled using 1000pF and 0.1µF capacitors.
V
CM
(Pin 6): Common Mode and DC Return for the I-Mixer
and Q-Mixer. An external resistor must be connected
between this pin and ground to set the DC bias current of
the I/Q demodulator.
EN (Pin 7): Enable Pin. When the input voltage is higher
than 1.6V, the circuit is completely turned on. When the
input voltage is less than 1.3V, the circuit is turned off.
PI FU CTIO S
UUU
LO
+
, LO
–
(Pins 10, 11): Differential Local Oscillator Input
Pins. These pins are internally biased to 2.44V. They can
be driven single-ended by connecting one to an AC ground
through a 1000pF capacitor. However, differential input
drive is recommended to minimize LO feedthrough to the
RF input pins.
Q
OUT
–
, Q
OUT
+
(Pins 13, 14): Differential Baseband Output
Pins of the Q-Channel. The internal DC bias voltage is V
CC
–0.85V for each pin.
I
OUT
–
, I
OUT
+
(Pins 15, 16): Differential Baseband Output
Pins of the I-Channel. The internal DC bias voltage is V
CC
–0.85V for each pin.
GROUND (Pin 17, Backside Contact): Ground Return for
the Entire IC. This pin must be soldered to the printed
circuit board ground plane.
BLOCK DIAGRA
W
RF
+
I
OUT
+
LO
+
LO
–
0°/90°
BIAS
16
I
OUT
–
15
Q
OUT
+
14
Q
OUT
–
13
LO BUFFERS
LPF
I-MIXER
LPF
Q-MIXER
2
5
V
CC
7
EN
1
GND GND
8
V
CC
9
4
V
CC
12
V
CC
RF
–
5515 BD
3
V
CM
6
17 10 11
RF AMP
