ADG467BRS Analog Devices Inc, ADG467BRS Datasheet - Page 10

• Manufacturer Part Number: ADG467BRS
• Description: IC CHAN PROTECTOR OCTAL 20-SSOP
• Manufacturer: Analog Devices Inc
• Series: ADG467r

Specifications of ADG467BRS

• Rohs Status: RoHS non-compliant
• Voltage - Clamping: ±40V
• Technology: Mixed Technology
• Number Of Circuits: 8
• Applications: General Purpose
• Package / Case: 20-SSOP
• Operating Temperature (min): -40C
• Operating Temperature (max): 85C
• Operating Temperature Classification: Industrial
• Mounting: Surface Mount
• Pin Count: 20
• Power (watts): -
• Voltage - Working: -
• Lead Free Status / RoHS Status: Not Compliant

ADG467
When a negative overvoltage is applied to the channel protector
circuit, the PMOS transistor enters a saturated mode of operation
as the drain voltage exceeds V
case of the positive overvoltage, the other MOS devices are
nonsaturated.
OVERVOLTAGE
1
V
TP
NEGATIVE
= PMOS THRESHOLD VOLTAGE (–1.5V).
(–20V)
Figure 24. Negative Overvoltage on the Channel Protector
SATURATED
NON-
V
DD
NMOS
(+15V)
OVERVOLTAGE
NEGATIVE
SATURATED
(–20V)
SS
− V
V
SS
PMOS
TP
(–15V)
(see Figure 24). As in the
V
SS
(–13.5V)
SATURATED
– V
TP
1
NON-
V
DD
NMOS
(+15V)
Rev. B | Page 10 of 16
The channel protector is also functional when the supply rails
are down (for example, power failure) or momentarily uncon-
nected (for example, rack system). This is where the channel
protector has an advantage over more conventional protection
methods such as diode clamping (see the Applications Information
section). When V
the current is limited to subnano-ampere levels (see Figure 25).
OVERVOLTAGE
POSITIVE OR
NEGATIVE
Figure 25. Channel Protector Supplies Equal to 0 V
DD
OFF
V
and V
NMOS
DD
(0V)
SS
equal 0 V, all transistors are off and
OFF
V
PMOS
SS
(0V)
(0V)
OFF
V
NMOS
DD
(0V)