TOTAL POWER INT'L
Test Configurations
Input Reflected-Ripple Current Test Setup
To Oscilloscope
+
Battery
+
Lin
Current
Probe
+Vin
+Out
Load
MIW1500 Series
Overcurrent Protection
To provide protection in a fault (output overload)
condition, the unit is equipped with internal current limiting
circuitry and can endure current limiting for an unlimited
duration. At the point of current-limit inception, the unit shifts
from voltage control to current control. The unit operates
normally once the output current is brought back into its
specified range.
DC / DC
Converter
-Vin
-Out
Cin
Input Source Impedance
Input reflected-ripple current is measured with a inductor
Lin (4.7uH) and Cin (220uF, ESR < 1.0[ at 100 KHz) to
simulate source impedance.
Capacitor Cin, offsets possible battery impedance.
Current ripple is measured at the input terminals of the
module, measurement bandwidth is 0-500 KHz.
The power module should be connected to a low
ac-impedance input source. Highly inductive source
impedances can affect the stability of the power module.
In applications where power is supplied over long lines
and output loading is high, it may be necessary to use a
capacitor at the input to ensure startup.
Capacitor mounted close to the power module helps
ensure stability of the unit, it is recommended to use a good
quality low Equivalent Series Resistance (ESR < 1.0[ at 100
KHz) capacitor of a 8.2uF for the 5V input devices, a 3.3uF for
the 12V input devices and a 1.5uF for the 24V devices.
Peak-to-Peak Output Noise Measurement Test
Use a Cout 0.47uF ceramic capacitor.
Scope measurement should be made by using a BNC
socket, measurement bandwidth is 0-20 MHz. Position the
load between 50 mm and 75 mm from the DC/DC Converter.
+Vin
+Out
Copper Strip
Cout
Resistive
Scope
Load
Output Ripple Reduction
+
DC Power
Source
-
+
Cin
-Vin
-Out
+Vin
DC / DC
Converter
+Out
Load
Single Output
DC / DC
Converter
-Vin
-Out
+Vin
+Out
Copper Strip
Cout
Cout
Scope
Resistive
Load
Scope
Dual Output
DC / DC
Com.
Converter
-Vin
-Out
A good quality low ESR capacitor placed as close as
practicable across the load will give the best ripple and
noise performance.
To reduce output ripple, it is recommended to use 3.3uF
capacitors at the output.
+
+Vin
+Out
Design & Feature Considerations
Maximum Capacitive Load
The MIW1500 series has limitation of maximum
connected capacitance at the output.
The power module may be operated in current limiting
mode during start-up, affecting the ramp-up and the startup
time.
For optimum performance we recommend 220uF
maximum capacitive load for dual outputs and 470uF
capacitive load for single outputs.
The maximum capacitance can be found in the data
.
DC Power
Source
-
-Vin
Single Output
DC / DC
Converter
-Out
Cout
Load
+
DC Power
Source
-
+Vin
+Out
Cout
Dual Output
DC / DC Com.
Converter
-Vin
-Out
Load
TOTAL-POWER [ TOTAL POWER INTERNATIONAL ]
