5567 查看數據表（PDF） - Linear Technology

零件编号

产品描述 (功能)

比赛名单

5567

14-Bit 80Msps Low Power 3V ADC

Linear Technology 

LTC5567

Applications Information

Introduction

The LTC5567 incorporates a high linearity double-balanced

active mixer, a high-speed limiting LO buffer and bias/

enable circuits. See the Pin Functions and Block Diagram

sections for a description of each pin. A test circuit sche-

matic showing all external components required for the

data sheet specified performance is shown in Figure 1.

A few additional components may be used to modify the

DC supply current or frequency response, which will be

discussed in the following sections.

The LO and RF inputs are single ended. The IF output is

differential. Low side or high side LO injection may be

used. The test circuit, shown in Figure 1, utilizes bandpass

IF output matching and an 8:1 IF transformer to realize a

50Ω single-ended IF output. The evaluation board layout

is shown in Figure 2.

RF Input

A simplified schematic of the mixer’s RF input is shown

in Figure 3. As shown, one terminal of the integrated RF

transformer’s primary winding is connected to Pin 3, while

the other terminal is DC-grounded internally. For this rea-

son, a series DC-blocking capacitor (C3) is needed if the

RF source has DC voltage present. The DC resistance of

the primary winding is approximately 4Ω. The secondary

winding of the RF transformer is internally connected to

the RF buffer amplifier.

The RF input is 50Ω matched from 1400MHz to 3000MHz

with a single 2.7pF series capacitor on the input. Matching

to RF frequencies above or below this frequency range is

easily accomplished by adding shunt capacitor C4, shown

in Figure 3. For RF frequencies below 500MHz, series

Figure 2. Evaluation Board Layout

5567f

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