ADL5562ACPZ-R7 datasheet(13/21 Pages) AD

13 / 21 page

Data Sheet

ADL5562

Rev. F | Page 13 of 21

CIRCUIT DESCRIPTION

BASIC STRUCTURE

The ADL5562 is a low noise, fully differential amplifier/ADC

driver that uses a 3.3 V supply. It provides three gain options

(6 dB, 12 dB, and 15.5 dB) without the need for external resistors

and has wide bandwidths of 2.6 GHz for 6 dB, 2.3 GHz for 12 dB,

and 2.1 GHz for 15.5 dB. Differential input impedance is 400 Ω

for 6 dB, 200 Ω for 12 dB, and 133 Ω for 15.5 dB. It has a

differential output impedance of 10 Ω and a common-mode

adjust voltage of 1.25 V to 1.85 V.

1/2 RS

200Ω

400Ω

0.1µF

400Ω

200Ω

100Ω

VIP2

VIP1

VIN1

VIN2

5Ω

Figure 32. Basic Structure

The ADL5562 is composed of a fully differential amplifier with

on-chip feedback and feed-forward resistors. The two feed-forward

resistors on each input set this pin-strappable amplifier in three

different gain configurations of 6 dB, 12 dB, and 15.5 dB. The

amplifier is designed to provide high differential open-loop gain

and an output common-mode circuit that enables the user to

change the common-mode voltage from a VCOM pin. The

amplifier is designed to provide superior low distortion at

frequencies up to and beyond 300 MHz with low noise and

low power consumption. The low distortion and noise are

realized with a 3.3 V power supply at 80 mA.

The ADL5562 is very flexible in terms of I/O coupling. It can

be ac-coupled or dc-coupled at the inputs and/or the outputs

within the specified input and output common-mode levels.

The input of the device can be configured as single-ended or

differential with similar distortion performance. Due to the

internal connections between the inputs and outputs, keep the

output common-mode voltage between 1.25 V and 1.85 V for

the best distortion. For a dc-coupled input, the input common

mode must be between 1 V and 2.3 V for the best distortion.

The device has been characterized using 2 V p-p into 200 Ω. If

the inputs are ac-coupled, the input and output common-mode

voltages are set by VCC/2 when no external circuitry is used.

The ADL5562 provides an output common-mode voltage set by

VCOM, which allows driving an ADC directly without external

components, such as a transformer or ac coupling capacitors,

provided the VCOM of the amplifier is within the VCOM of the

ADC. For dc-coupled requirements, the input VCM must be set

by the VCOM pin in all three gain settings.

ADL5562ACPZ-R7 Scheda tecnica(PDF) 13 Page - Analog Devices

ADL5562ACPZ-R7 Scheda tecnica(HTML) 13 Page - Analog Devices

Html Pages

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21

Scheda tecnica Scarica

Link URL