lt5511 Linear Technology Corporation, lt5511 Datasheet - Page 8

• Manufacturer Part Number: lt5511
• Description: High Signal Level Upconverting Mixer
• Manufacturer: Linear Technology Corporation

BLOCK DIAGRA
PI FU CTIO S
LT5511
LO
Oscillator Signal. They can also be driven single-ended by
connecting one to an RF ground through a DC blocking
capacitor. For single-ended drive, use LO
input, as this results in less interference from unwanted
coupling of the LO signal to other pins. These pins are
internally biased to about 1.4V; thus, DC blocking capaci-
tors are required. An impedance transformation is re-
quired to match the LO input to 50 (or 75 ). At frequen-
cies below 1.5GHz this input can be resistively matched
with a shunt resistor.
NC (Pins 2, 9): Not Connected Internally. Connect to
ground for improved isolation between pins.
GND (Pins 3, 6, 8,11, 14): Internal Grounds. These pins
are used to improve isolation and are not intended as DC
or RF grounds for the IC. Connect these pins to ground for
best performance.
IF
differential signal must be applied to these pins. These
pins are internally biased to about 1.2V, and thus require
DC blocking capacitors. These pins should be DC isolated
from each other for best LO suppression. Imbalances in
amplitude or phase between these two signals will de-
grade the linearity of the mixer.
8
+
–
U
, IF
, LO
–
(Pins 4, 5): Differential Inputs for the IF Signal. A
+
U
(Pins 1, 16): Differential Inputs for the Local
U
W
V
CC
BIAS
GND
GND
NC
IF
IF
+
–
+
2
3
4
5
6
7
for the signal
GND
8
LO
1
(BACKSIDE)
–
CIRCUITS
BIAS
GND
17
V
Enable Circuits. This pin should be connected to V
have appropriate RF bypass capacitors. Care should be
taken to ensure that RF signal leakage to the V
minimized.
EN (Pin 10): Chip Enable/Disable. When the applied volt-
age is greater than 3V, the IC is enabled. When the applied
voltage is less than 0.5V, the IC is disabled and the DC
current drops to about 1 A. Under no conditions should
the voltage on this pin exceed V
on.
RF
Output Signal. An impedance transformation may be
required to match the outputs. These pins are also used to
connect the mixer to the DC supply through impedance-
matching inductors, RF chokes or transformer center-tap.
Care should be taken to ensure that the RF signal leakage
to V
V
fier. This pin should be connected to V
priate RF bypass capacitors. Care should be taken to
ensure that RF signal leakage to the V
GROUND (Backside Contact) (Pin 17): DC and RF Ground
Return for the Entire IC. This contact must be connected
to a low impedance ground plane for proper operation.
LO
CC
CC
BUFFER
16
–
+
LO
BIAS (Pin 7): Supply Voltage for the LO Buffer Bias and
LO (Pin 15): Supply Voltage for the LO Buffer Ampli-
NC
, RF
CC
9
LO and V
+
(Pins 12, 13): Differential Outputs for the RF
15
14
13
12
11
10
CC
V CC LO
GND
RF
RF
GND
EN
BIAS is minimized.
5511 BD
+
–
CC
+ 0.3V, even at power
CC
CC
line is minimized.
and have appro-
CC
CC
line is
and
5511f