TOTAL POWER INT'L
MIW1500 Series
Te s t Configura tions
Ove rcurre nt P rote ction
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.
Input Reflected-Ripple Current Test Setup
To Oscilloscope
+Vin
+Out
+
+
Lin
DC / DC
Converter
Current
Probe
Load
Battery
Cin
-Vin
-Out
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 a t the input to ensure startup.
Peak-to-Peak Output Noise Measurement Test
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 .
Output Ripple Re duction
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
+Vin
+Out
Copper Strip
Cout
+
DC / DC
Converter
DC Power
Source
Single Output
DC / DC
Converter
Load
Resistive
Load
Scope
Cin
-
-Vin
-Out
-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 us e 3.3uF
capacitors at the output.
Copper Strip
Cout
+Vin
+Out
Com.
-Out
Scope
Scope
Dual Output
DC / DC
Converter
Resistive
Load
Cout
-Vin
+
+Vin
+Out
Single Output
DC Power
Source
DC / DC
Converter
De s ign & Fe a ture Cons ide ra tions
Cout
Load
-
-Vin
-Out
Ma ximum Ca pa citive Loa d
The MIW1500 series has limitation of maximum
connected capacitance a t the output.
The power module may be operate d 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.
+
+Vin
-Vin
+Out
Dual Output
Cout
Load
DC Power
Source
DC / DC Com.
Converter
-
-Out
The maximum capacitance can be found in the data .
TOTAL-POWER [ TOTAL POWER INTERNATIONAL ]
