The ADG467 is an octal channel protector. The channel protector is placed in series with the signal path. The channel protector protects sensitive components from voltage transience in the signal path regardless if the power supplies are present or not. For this reason, the channel protectors are ideal for use in applications where correct power sequencing cannot always be guaranteed (for example, hot insertion rack systems) to protect analog inputs.
Each channel protector has an independent operation and consists of an N-channel MOSFET, a P-channel MOSFET, and an N-channel MOSFET, connected in series. The channel protector behaves just like a series resistor during normal operation, that is, (VSS + 1.5 V) < VIN < (VDD − 1.5 V). When a channel’s analog input exceeds the power supplies (including VDD and VSS = 0 V), one of the MOSFETs switches off, clamping the output to either VSS + 1.5 V or VDD − 1.5 V. Circuitry and signal source protection is provided in the event of an overvoltage or power loss. The channel protectors can withstand overvoltage inputs from −40 V to +40 V.
The ADG467 can operate off both bipolar and unipolar supplies. The channels are normally on when power is connected and open circuit when power is disconnected. With power supplies of ±15 V, the on resistance of the ADG467 is 62 Ω typical with a leakage current of ±1 nA maximum. When power is disconnected, the input leakage current is approximately ±0.5 nA typical.
The ADG467 is available in an 18-lead SOIC package and a 20-lead SSOP package.
- Fault Protection.
The ADG467 can withstand continuous voltage inputs from −40 V to +40 V. When a fault occurs due to the power supplies being turned off or due to an overvoltage being applied to the ADG467, the output is clamped. When power is turned off, current is limited to the microampere level.
- Low Power Dissipation.
- Low RON. 62 Ω typical.
- Trench Isolation Latch-Up Proof Construction.
A dielectric trench separates the p- and n-channel MOSFETs thereby preventing latch-up.
- ATE equipment
- Sensitive measurement equipment
- Hot insertion rack systems
At least one model within this product family is in production and available for purchase. The product is appropriate for new designs but newer alternatives may exist.
Product Selection Guide
Switches and Multiplexers Product Selection Guide
Data-acquisition system uses fault protection
By Catherine Redmond, Analog Devices, Inc. (EDN, 4/15/2004)
CMOS Switches Offer High Performance in Low Power, Wideband Applications
by Theresa Corrigan and Ray Goggin, Analog Devices, Inc. (High Frequency Electronics, February 2004)
Temperature monitor measures three thermal zones
by Susan Pratt, Analog Devices, Inc. (EDN, 12/11/03)
Enhanced Multiplexing for MEMS Optical Cross Connects
by James Caffrey (Fiberoptic Product News, 8/2003)
Rarely Asked Questions
What shall we do with an unused op-amp?
Rarely Asked Questions
Glass Diodes May See the Light — and Hum
ADI has always placed the highest emphasis on delivering products that meet the maximum levels of quality and reliability. We achieve this by incorporating quality and reliability checks in every scope of product and process design, and in the manufacturing process as well. "Zero defects" for shipped products is always our goal.
The USA list pricing shown is for BUDGETARY USE ONLY, shown in United States dollars (FOB USA per unit for the stated volume), and is subject to change. International prices may differ due to local duties, taxes, fees and exchange rates. For volume-specific price or delivery quotes, please contact your local Analog Devices, Inc. sales office or authorized distributor. Pricing displayed for Evaluation Boards and Kits is based on 1-piece pricing.