ADG466_15 Datasheet, PDF (1/8 Pages) Analog Devices – Triple and Octal Channel Protectors

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Triple and Octal
Channel Protectors
ADG466/ADG467
FEATURES
Fault and Overvoltage Protection up to ؎40 V
FUNCTIONAL BLOCK DIAGRAMS
Signal Paths Open Circuit with Power Off
Signal Path Resistance of R_ON with Power On
44 V Supply Maximum Ratings
Low On Resistance
V_DD V_SS
V_D1
V_S1
V_DD V_SS
V_D1
V_S1
ADG466/ADG467 60 ⍀ typ
V_D2
V_S2
V_D2
V_S2
OBSOLETE 1 nA Max Path Current Leakage @ +25؇C
Low R_ON Match (5 ⍀ max)
Low Power Dissipation 0.8 ␮W typ
Latch-Up Proof Construction
APPLICATIONS
ATE Equipment
Sensitive Measurement Equipment
Hot-Insertion Rack Systems
V_D3
V_S3
V_D3
V_S3
ADG466
V_IN
V_IN
V_DD
V_D8
V_S8
V_OUT
ADG467
V_OUT
V_DD
GENERAL DESCRIPTION
The ADG466 and ADG467 are triple and octal channel pro-
tectors, respectively. The channel protector is placed in series
with the signal path. The channel protector will protect sensitive
components from voltage transience in the signal path whether
the power supplies are present or not. Because the channel
protection works whether the supplies are present or not, the
OUTPUT CLAMPED
@ V_DD – 1.5V
ADG467 is 50 Ω typ with a leakage current of ± 1 nA max.
channel protectors are ideal for use in applications where
When power is disconnected, the input leakage current is
correct power sequencing can’t always be guaranteed (e.g.,
approximately ± 5 nA typ.
hot-insertion rack systems) to protect analog inputs. This is
discussed further, and some example circuits are given in the
“Applications” section of this data sheet.
The ADG466 is available in 8-lead DIP, SOIC and µSOIC
packages. The ADG467 is available in an 18-lead SOIC package
and a 20-lead SSOP package.
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, i.e., (V_SS + 2 V) < V_IN < (V_DD – 1.5 V). When a
channel’s analog input exceeds the power supplies (including
V_DD and V_SS = 0 V), one of the MOSFETs will switch off,
clamping the output to either V_SS + 2 V or V_DD – 1.5 V. Circuitry
and signal source protection is provided in the event of an
PRODUCT HIGHLIGHTS
1. Fault Protection.
The ADG466 and 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 overvolt-
age being applied to the ADG466 and ADG467, the output
is clamped. When power is turned off, current is limited to
the microampere level.
overvoltage or power loss. The channel protectors can withstand
overvoltage inputs from –40 V to +40 V. See the “Circuit
Information” section of this data sheet.
The ADG466 and 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 ADG466 and
2. Low Power Dissipation.
3. Low R_ON.
ADG466/ADG467 60 Ω typ.
4. Trench Isolation Latch-Up Proof Construction.
A dielectric trench separates the p- and n-channel MOSFETs
thereby preventing latch-up.
REV. 0
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© Analog Devices, Inc., 1996