AD8108 325 MHz, 8 x 8 Buffered Video Crosspoint Switch (Gain = 1)

The AD8108/AD8109 are high speed 8 × 8 video crosspoint switch matrices. They offer a −3 dB signal bandwidth greater than 250 MHz and channel switch times of less than 25 ns with 1% settling. With −83 dB of crosstalk and −98 dB isolation (at 5 MHz), the AD8108/AD8109 are useful in many high speed applications. The differential gain and differential phase of better than 0.02% and 0.02°, respectively, along with 0.1 dB flatness out to 60 MHz, make the AD8108/AD8109 ideal for video signal switching.

The AD8108 and AD8109 include eight independent output buffers that can be placed into a high impedance state for paralleling crosspoint outputs so that off channels do not load the output bus. The AD8108 has a gain of 1, while the AD8109 offers a gain of 2. They operate on voltage supplies of ±5 V while consuming only 45 mA of idle current. The channel switching is performed via a serial digital control (which can accommodate daisy-chaining of several devices) or via a parallel control allowing updating of an individual output without reprogramming the entire array.

The AD8108/AD8109 is packaged in an 80-lead LQFP and is available over the extended industrial temperature range of −40°C to +85°C.

Applications

Features and Benefits

8 × 8 high speed nonblocking switch arrays: G = 1

Serial or parallel programming of switch array

Serial data out allows daisy-chaining of multiple 8 × 8 arrays to create larger switch arrays

Output disable allows connection of multiple devices

Pin-compatible with AD8110/AD8111 16 × 8 switch arrays

For 16 × 16 arrays see AD8116

Complete solution

Buffered inputs
Eight output amplifiers: G = 1
Drives 150 Ω loads

Buffered inputs

Eight output amplifiers: G = 1

Drives 150 Ω loads

Excellent video performance

60 MHz 0.1 dB gain flatness
0.02%/0.02° differential gain/differential phase error (RL = 150 Ω)

60 MHz 0.1 dB gain flatness

0.02%/0.02° differential gain/differential phase error (RL = 150 Ω)

Excellent ac performance

−3 dB bandwidth: 325 MHz
Slew rate: 400 V/µs

−3 dB bandwidth: 325 MHz

Slew rate: 400 V/µs

Low power of 45 mA

Low all hostile crosstalk of −83 dB at 5 MHz

Reset pin allows disabling of all outputs (connected through a capacitor to ground provides power-on reset capability)

Excellent ESD rating: exceeds 4000 V human body model

80-lead LQFP (12 mm × 12 mm)

Switches & Multiplexers

Buffered Analog Crosspoint Switches

Data Sheets

Document	note
AD8108/AD8109: 325 MHz, 8 x 8 Buffered Video Crosspoint Switches Data Sheet (Rev. C)	PDF 462.27 K

Application Notes

Document	note
AN-282: Fundamentals of Sampled Data Systems	PDF 2131 kB
AN-214: Ground Rules for High Speed Circuits	PDF 356 kB

Order Information

Part Number	Package	Packing Qty	Temp Range	Price 100-499	Price 1000+	RoHS
AD8108ASTZ Production	80 ld LQFP (12x12x1.4mm)	OTH 119	-40 to 85C	23.78	20.22	Y

Reference Materials

Product Selection Guide：High Speed Switches
Technical Articles：CMOS Switches Offer High Performance in Low Power, Wideband Applications

AD8108/AD8109: 325 MHz, 8 x 8 Buffered Video Crosspoint Switches Data Sheet (Rev. C) ad8108

AN-282: Fundamentals of Sampled Data Systems ad1674

AN-214: Ground Rules for High Speed Circuits ad1674

AN-282: 采样数据系统基本原理[中文版] (Rev. A) ad75019

High Speed Switches ad75019

CMOS Switches Offer High Performance in Low Power, Wideband Applications ad75019