LT5515 LINER [Linear Technology], LT5515 Datasheet - Page 6

• Manufacturer Part Number: LT5515
• Description: 1.5GHz to 2.5GHz Direct Conversion Quadrature Demodulator
• Manufacturer: LINER [Linear Technology]

PI FU CTIO S
LT5515
GND (Pins 1, 4): Ground Pin.
RF
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
should be decoupled using 1000pF and 0.1µF capacitors.
V
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.
BLOCK DIAGRA
6
CC
CM
U
+
, RF
(Pins 5, 8, 9, 12): Power Supply Pins. These pins
(Pin 6): Common Mode and DC Return for the I-Mixer
–
(Pins 2, 3): Differential RF Input Pins. These
U
U
V
W
RF
RF
CM
+
–
2
3
6
BIAS
V
EN
5
RF AMP
7
CC
V
CC
8
GND GND
1
V
9
CC
4
V
12
CC
LO BUFFERS
Q-MIXER
17
I-MIXER
LO
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
Pins of the Q-Channel. The internal DC bias voltage is V
–0.85V for each pin.
I
Pins of the I-Channel. The internal DC bias voltage is V
–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.
OUT
OUT
LO
10
+
0°/90°
+
, LO
–
–
, I
, Q
LO
11
OUT
–
–
OUT
(Pins 10, 11): Differential Local Oscillator Input
+
LPF
LPF
+
(Pins 15, 16): Differential Baseband Output
(Pins 13, 14): Differential Baseband Output
16
15
14
13
I
I
Q
Q
OUT
OUT
5515 BD
OUT
OUT
+
–
+
–
5515fa
CC
CC