LT5575

9

5575f

BLOCK DIAGRAM

PIN FUNCTIONS

GND (Pins 1, 3, 4, 9, 11): Ground pin.

RF (Pin 2):

RF Input Pin. This is a single-ended 50Ω ter-

minated input. No external matching network is required

for the high frequency band. An external series capacitor

(and/or shunt capacitor) may be required for impedance

transformation to 50Ω in the low frequency band from

800MHz to 1.5GHz (see Figure 4). If the RF source is not

DC blocked, a series blocking capacitor should be used.

Otherwise, damage to the IC may result.

should be decoupled using 1000pF and 0.1µF capacitors.

EN (Pin 5): Enable Pin. When the input voltage is higher

than 2.0V, the circuit is completely turned on. When the

enable pin voltage is less than 1.0V, the circuit is turned

off. Under no conditions should the voltage at the EN

result. If the Enable function is not needed, then the EN

LO (Pin 10):

Local Oscillator Input Pin. This is a single-

ended 50Ω terminated input. No external matching net-

work is required in the high frequency band. An external

shunt capacitor (and/or series capacitor) may be required

for impedance transformation to 50Ω for the low frequency

band from 800MHz to 1.5GHz (see Figure 6). If the LO

source is not DC blocked, a series blocking capacitor must

be used. Otherwise, damage to the IC may result.

OUT

Output Pins of the Q Channel. The internal DC bias voltage

OUT

Output Pins of the I Channel. The internal DC bias voltage

Exposed Pad (Pin 17): Ground Return for the Entire IC.

This pin must be soldered to the printed circuit board

ground plane.

RF

+

LO

GND

0

°/90°

16

–

15

+

14

–

13

LO BUFFERS

LPF

I-MIXER

LPF

Q-MIXER

EXPOSED

PAD

6

BIAS

5

EN

1

GND

7

8

4

12

GND

5575 BD

9

17

RF AMP

RF AMP

2

3

11

10