Specifications

POWER SUPPLY
TESTING
For design testing and
verification, the need for
regulated power supplies are
increasing with ongoing
advancement in technology.
More so, it has become a
necessity in newer electronic
devices to be tested with
precise and sophisticated
power supplies. There are
some specifications that
determine some underlying
performance factors in typical
power supplies. Particularly,
the load transient response,
load regulation, and current
limit. In the following
sections, each of these factors
are addressed as an example
to describe and demonstrate
the setup, configuration, and
equipment required for testing
and verification. Each
example will utilize B&K
Precision's 8500 DC load as
part of the setup.
Disclaimer: The following
sections include general
setups with some settings
specified for the test
environment. Some details
are ignored, and therefore
results may vary and may not
reflect exactly what is shown
in the following sections.
Load Transient
Response
An important element to
power supply testing is a
measurable unit of load
transient response, which
characterizes the capability of
the power supply to stabilize
itself upon a step change in
the load current. In order to
verify the response,
measurements of the rise and
fall times upon a step change
in the load is necessary.
Generally, this type of test
requires a load that is able to
produce a rise and fall time
approximately five times
faster than the power supply.
The following application
demonstrates an effective
approach to testing the load
transient response of a B&K
Precision power supply model
9130.
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Figure 2. Transient Response for B&K Precision 9130
Figure 1. Load Transient Response Test Setup
Power Supply
Settings: 5 V
Limit: 3.1 A
+ -
Digital Oscilloscope
Trigger: negative slope
DC Load
Mode: Transient
Trigger: Pulse 0.1 A to 3.0 A
+ -