ad8260 Analog Devices, Inc., ad8260 Datasheet

ad8260

Manufacturer Part Number

ad8260

Description

High Current Driver Amplifier And Digital Vga/preamplifier With 3 Db Steps

Manufacturer

Analog Devices, Inc.

Datasheet

1.AD8260.pdf (32 pages)

Current page: 1 of 32
Download datasheet (2Mb)

FEATURES

High current driver

VGA/preamplifier

Supplies: 3.3 V to 10 V (with VMID enabled)

Power: 93 mW with 3.3 V supplies

APPLICATIONS

Digital AGC systems

Tx/Rx signal processing

Power line transceivers

GENERAL DESCRIPTION

The AD8260 includes a high current driver, usable as a

transmitter, and a low noise digitally programmable variable

gain amplifier (DGA), useable as a receiver.

The receiver section consists of a single-ended input preampli-

fier, and linear-in-dB, differential-output DGA. The receiver has

a small signal –3 dB bandwidth of 230 MHz; the driver small

signal bandwidth is 195 MHz. The driver delivers ±300 mA,

well suited for driving low impedance loads, even when

connected to a 3.3 V supply.

The AD8260 DGA is ideal for trim applications and has a gain

span of 30 dB, in 3 dB steps. Excellent bandwidth uniformity is

maintained across the entire frequency range. The low output-

referred noise of the DGA is advantageous in driving high

speed ADCs. The differential output facilitates the interface to

modern low voltage high speed ADCs.

Single-supply and dual-supply operation makes the part versatile

and enables gain control of negative-going pulses, such as those

generated by photodiodes or photo-multiplier tubes, as well as

processing band-pass signals on a single supply. For maximum

Rev. 0

Information furnished by Analog Devices is believed to be accurate and reliable. However, no

responsibility is assumed by Analog Devices for its use, nor for any infringements of patents or other

rights of third parties that may result from its use. Specifications subject to change without notice. No

license is granted by implication or otherwise under any patent or patent rights of Analog Devices.

Trademarks and registered trademarks are the property of their respective owners.

Differential input—direct drive from DAC

Preset gain: 1.5×

−3 dB bandwidth: 195 MHz

Large output drive: >±300 mA

Low noise

−3 dB bandwidth: 230 MHz

Gain range: 30 dB in 3 dB steps

Single-ended preamplifier input and differential VGA

±3.3 V to ±5 V (with VMID disabled)

Power-down for VGA, driver amplifier, and system

Voltage noise: 2.4 nV/√Hz

Current noise: 5 pA/√Hz

−6 dB to +24 dB (for preamplifier gain of 6 dB)

output

Digital VGA/Preamplifier with 3 dB Steps

High Current Driver Amplifier and

One Technology Way, P.O. Box 9106, Norwood, MA 02062-9106, U.S.A.

Tel: 781.329.4700

Fax: 781.461.3113

dynamic range, it is essential that the part be ac-coupled when

operating on a single supply.

The AD8260 preamplifier (PrA) is configured with external

resistors for gains greater than 6 dB and can be inverting or

noninverting. The DGA is characterized with a noninverting

preamplifier gain of 2×. The attenuator has a range of 30 dB and

the output amplifier has a gain of 8× (18.06 dB). The lowest

noninverting gain range is −6 dB to +24 dB and shifts up with

increased preamplifier gain. The gain is controlled via a parallel

port (Pin GNS0 to Pin GNS3) with 10 gain steps of 3 dB per

code. The preamplifier and DGA are disabled for any code that

is not assigned a gain step.

The AD8260 can operate with single or dual supplies from 3.3 V

to ±5 V. An internal buffer normally provides a split supply

reference for single-supply operation; an external reference

can also be used when the VMID buffer is shut down.

The operating temperature range is −40°C to +105°C. The

AD8260 is available in a 5 mm × 5 mm, 32-lead LFCSP.

VMDO

VNCM

VGAN

VGAP

VPSB

ENBL

TXEN

VMDI

VOCM INPP INRP INRN INPN TXFB VNEG

VNGR VPSR GNS3 GNS2 GNS1 GNS0 PRAO VNGR

FUNCTIONAL BLOCK DIAGRAM

1.5kΩ

VMID

Figure 1. Functional Block Diagram

1kΩ

HIGH CURRENT DRIVER

ATTENUATOR

GM STAGES

AD8260

LOGIC

BIAS

1kΩ

VGA/PREAMPLIFIER

1.5kΩ

–

×1

AD8260

www.analog.com

VNEG

TXOP

VPOS

VPSR

VMDO

PRAI

FDBK

Related parts for ad8260

Related keywords

ad8260 datasheet
ad8260 data sheet
ad8260 pdf datasheet
ad8260 component
ad8260 part
ad8260 distributor
ad8260 RoHS
ad8260 datasheet download