lt5503 Linear Technology Corporation, lt5503 Datasheet - Page 10

• Manufacturer Part Number: lt5503
• Description: 1.2ghz To 2.7ghz Direct Iq Modulator And Mixer
• Manufacturer: Linear Technology Corporation

PI FU CTIO S
LT5503
BQ
Q-Channel. This pin is internally biased to 1.4V, but can
also be overdriven with an external DC voltage greater than
1.4V, but less than V
BQ
Channel. This pin is internally biased to 1.4V, but can also
be overdriven with an external DC voltage greater than
1.4V, but less than V
GC1 (Pin 3): Gain Control Pin. This pin is the least
significant bit of the four-step modulator gain control.
MODIN (Pin 4): Modulator Carrier Input Pin. This pin is
internally biased and should be AC-coupled. An external
matching network is required for a 50 source.
V
This pin should be externally connected to the other V
pins and decoupled with 1000pF and 0.1 F capacitors.
V
Input RF Buffer and Phase Shifter. This pin should be
externally connected to the other V
with 1000pF and 0.1 F capacitors.
LO1 (Pin 7): Mixer 1st LO Input Pin. This pin is internally
biased and should be AC-coupled. An external matching
network is required for a 50 source.
V
Circuits. This pin should be externally connected to the
other V
capacitors.
DMODE (Pin 9): Mixer 2nd LO Divider Mode Control Pin.
Low = divide-by-2, High = divide-by-1.
MX
be connected to V
work.
MX
be connected to V
work.
10
CC
CC
CC
U
–
+
+
–
MOD (Pin 5): Power Supply Pin for the I/Q Modulator.
RF (Pin 6): Power Supply Pin for the I/Q Modulator
LO1 (Pin 8): Power Supply Pin for the Mixer LO1
(Pin 1): Negative Baseband Input Pin of the Modulator
(Pin 2): Positive Baseband Input Pin of Modulator Q-
(Pin 10): Mixer Positive RF Output Pin. This pin must
(Pin 11): Mixer Negative RF Output Pin. This pin must
CC
U
pins and decoupled with 1000pF and 0.1 F
CC
CC
U
CC
CC
through an external matching net-
through an external matching net-
– 0.4V.
– 0.4V.
CC
pins and decoupled
CC
MIXEN (Pin 12): Mixer Enable Pin. When the input voltage
is higher than V
through pins 8, 10, 11 and 15 are enabled. When the input
voltage is less than 0.4V, these circuits are disabled.
MODEN (Pin 13): Modulator Enable Pin. When the input
voltage is higher than V
supplied through pins 5, 6, 16 and 17 are enabled. When
the input voltage is less than 0.4V, these circuits are
disabled.
LO2 (Pin 14): Mixer 2nd LO Input Pin. This pin is internally
biased and should be AC-coupled. An external matching
network is not required, but can be used for improved
matching to a 50 source.
V
Circuits. This pin should be externally connected to the
other V
capacitors.
V
Variable Gain Amplifier. This pin should be externally
connected to the other V
and decoupled with a good high frequency capacitor (2pF
typical) placed close to the pin.
MODOUT (Pin 17): Modulator RF Output Pin. This pin
must be externally biased to V
external matching network is required to match to 50 .
GC2 (Pin 18): Gain Control Pin. This pin is the most
significant bit of the four-step modulator gain control.
BI
I-Channel. This pin is internally biased to 1.4V, but can also
be overdriven with an external DC voltage greater than
1.4V, but less than V
BI
tor I-Channel. This pin is internally biased to 1.4V, but can
also be overdriven with an external DC voltage greater than
1.4V, but less than V
GROUND (Backside Contact): Circuit Ground Return for
the Entire IC.
CC
CC
+
–
(Pin 19): Positive Baseband Input Pin of the Modulator
LO2 (Pin 15): Power Supply Pin for the Mixer LO2
VGA (Pin 16): Power Supply Pin for the Modulator
(Pin 20): Negative Baseband Input Pin of the Modula-
CC
pins and decoupled with 1000pF and 0.1 F
CC
– 0.4V, the mixer circuits supplied
CC
CC
CC
– 0.4V.
– 0.4V.
CC
– 0.4V, the modulator circuits
pins through a 47 resistor
CC
through a bias choke. An