SCANSTA476 Eight Input IEEE 1149.1 Analog Voltage Monitor
April 2005
SCANSTA476
Eight Input IEEE 1149.1 Analog Voltage Monitor
General Description
The SCANSTA476 is a low power, Analog Voltage Monitor
used for sampling or monitoring up to 8 analog/mixed-signal
input channels. Analog Voltage Monitors are valuable during
product development, environmental test, production, and
field service for verifying and monitoring power supply and
reference voltages. In a supervisory role, the 鈥橲TA476 is
useful for card or system-level health monitoring and prog-
nostics applications.
Instead of requiring an external microcontroller with a GPIO
interface, the 鈥橲TA476 features a common IEEE 1149.1
(JTAG) interface to select the analog input, initiate a mea-
surement, and access the results - further extending the
capabilities of an existing JTAG infrastructure.
The SCANSTA476 uses the V
REF
input as a reference. This
enables the SCANSTA476 to operate with a full-scale input
range of 0 to V
DD
, which can range from +2.7V to +5.5V.
The SCANSTA476 is packaged in a 16-lead non-pullback
LLP package that provides an extremely small footprint for
applications where space is a critical consideration. This
product operates over the industrial temperature range of
鈭?0藲C to +85藲C.
Features
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Eight selectable Analog input channels
Analog full-scale input range 0V to V
DD
Typical accuracy of 2 mV at maximum V
DD
Very low power operation
Small package footprint in 16-lead, 5 x 5 x 0.8 mm LLP
Single +2.7V to +5.5V supply operation
IEEE 1149.1 (JTAG) compliant interface
Applications
Measurement of Point Voltages
Real-time Signal Monitoring
System Health Monitoring and Prognostics
Debug, Environmental Test, Production Test, Field
Service
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Supplement In-Circuit Tester (ICT) access
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Vital in Servers, Computing, Telecommunication and
Industrial equipment
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Essential in Medical, Data Storage, and Networking
equipment
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Block Diagram
20083521
漏 2005 National Semiconductor Corporation
DS200835
www.national.com
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