Single Channel Protector in an SOT-23 Package and a MSOP Package
The ADG465 is a single channel protector that comes in SOT-23 and MSOP packages. The channel protector is in series with the signal path and protects sensitive components from voltage transience in the signal path whether or not the power supplies are present. Because the channel protection works regardless of the presence of the supplies, the channel protectors are ideal for use in applications where correct power sequencing cannot always be guaranteed to protect the analog inputs (for example, hot insertion rack systems).
A channel protector consists of an N channel, metal-oxide semiconductor field-effect transistor (MOSFET), a P channel MOSFET, and another N channel MOSFET connected in series. The channel protector behaves like a series resistor during normal operation, that is, (VSS + 1.5 V) < VIN < (VDD − 1.5 V). When the analog input of a channel 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 are provided in the event of an overvoltage or power loss. The channel protectors can withstand overvoltage inputs from −40 V to +40 V.
The ADG465 can operate from 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 ADG465 is 80 Ω typical, with a leakage current of ±1 nA maximum. When power is disconnected, the input leakage current is approximately ±0.005 μA typical. The ADG465 is available in a 6-lead SOT-23 package, and an 8-lead MSOP package.
- Fault Protection.
The ADG465 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 ADG465, the output is clamped. When power is turned off, current is limited to the nanoampere level.
- Low Power Dissipation.
- Low RON 80 Ω typical.
- Trench Isolation Latch-Up Proof Construction.
A dielectric trench separates the P channel and the N channel MOSFETs thereby preventing latch up.
- ATE Equipment
- Sensitive measurement equipment
- Hot insertion rack systems
- ADC input channel protection
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.
A device can be clamped or soldered to the center of the evaluation board. Each pin of the device has a corresponding link from K1 to K6 that can be set to either VDD or GND. A wire screw terminal supplies VDD and GND. SMB connectors on the board allow additional external signals to be supplied to the device. In addition, there is space available at the top of the board for prototyping.
Full specifications of the device under test (DUT) are available in the corresponding product data sheet, which should be consulted in conjunction with user guide UG- 948 when using the evaluation board.
The EVAL-8MSOPEBZ is the evaluation board for the 8 lead MSOP devices in the switch/mux portfolio which are to be purchased separately. A clamp is supplied with the board so that the device can be secured to the board without the need for soldering. This makes the board reusable for multiple devices.
The device can be clamped or soldered to the center of the evaluation board. Each pin of the device is broke out to a link that can be set to either VDD or GND and a wire screw terminal is provided to supply VDD and GND. SMB connectors are on the board allow for additional external signals to be supplied to the device. In addition, there is space at the top of the board available for prototyping.
Full specifications of the device under test are available in the product data sheet, which should be consulted in conjunction with this user guide when using the evaluation board.
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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.
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