D12S400-A Datasheet, PDF (8/12 Pages) Delta Electronics, Inc. – Delphi D12S400 Non-Isolated Point of Load DC/DC Modules

FEATURES DESCRIPTIONS (CONT.)
Output Voltage Programming
The output voltage of the D12S400 is trimmable by
connecting an external resistor between the Trim(+) and
Trim(-) pins as shown in Figure 26 and the typical trim
resistor values are shown in Table 1.
Unit
Vin
Enable
GND
Vout
Trim(+)
Trim(-)
Rtrim
Figure 26: Trimming Output Voltage
The D12S400 module has a trim range of 0.8375V to
5.0V. The trim resistor equation for the D12S400 is:
Rtrim()  ^1.675
Vout  0.8375
Vout is the output voltage set point
Rtrim is the resistance between Trim(+) and Trim(-)
Rtrim values should not be less than 360Ω
Output Voltage
0.8375V
+1.0V
+1.2V
+1.5V
+1.8V
+2.5V
+3.3V
+5.0V
Rtrim (Ω)
open
10.3K
4.631K
2.528K
1.74K
1.008K
680
402
Table 1: Typical trim resistor values
Power Good
The converter provides an open collector signal called Power
Good. This output pin uses positive logic and is open-drain. This
power good output is able to sink 4mA.
The power good signal is pulled low when an input under
voltage, output over voltage, or output over current conditions is
detected or when the converter is disabled by ENABLE pin.
Paralleling
D12S400 converters do not have built-in current sharing
(paralleling) ability. Hence, paralleling of multiple D12S400
converters are not recommended.
Output Capacitance
There is output capacitor on the D12S400. Hence, no external
output capacitor is required for stable operation.
Reflected Ripple Current and Output Ripple and
Noise Measurement
The measurement set-up outlined in Figure 27 has been used
for both input reflected/ terminal ripple current and output
voltage ripple and noise measurements on D12S400
converters.
Input reflected current measurement point
Vin+
Ltest
DC-DC Converter
Cs
Cin
1uF
Ceramic
10uF
Tan
Load
Output voltage ripple noise measurement point
Cs=330μF OS-CON cap x 1, Ltest=1μH, Cin=330μF
OS-CON cap x 1,
Figure 27: Input reflected ripple/ capacitor ripple current and
output voltage ripple and noise measurement setup for
D12S400
DS_D12S400_10152013
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