E2S Series – Eighth-Brick DC/DC Converter
48V Input
Data Sheet
5.0V, 3.3V, 2.5V, 2.0V, 1.8V, 1.5V, 1.2V Output
REV. MAR 11, 2003
Page 4 of 10
Output Voltage Trim
The trim feature allows the user to adjust the
output voltage from the nominal value. This can
be used to compensate distribution drops,
perform margining in production, or accommodate
other requirements when output voltage needs to
be adjusted from the nominal.
The converter’s output voltage (at the terminals)
can be adjusted up 10% or down 20% relative to
the nominal output voltage by connecting the
TRIM pin to sense (+) or sense (-) via a trim
resistor. The Trim pin should be left open if the
trimming function is not to be used.
To trim up the output voltage, a trim resistor, RT-
INCR, should be connected between TRIM (Pin 6)
and SENSE(+) (Pin 7), as illustrated in Fig. 1.
The trim-up resistor can be calculated from:
Figure 1. Output Voltage Trim-up
5.1(100+)VO-NOM – 624.75
RT-INCR =
__________________________________ - 10.2 [K]
1.225
where,
RT-INCR Required value of trim-up resistor
VO-NOM = Nominal value of output voltage
insert absolute value bars
VO-REQ - VO-NOM
=
_________________________
x 100
[%]
VO-NOM
VO-REQ = Desired (trimmed) output voltage
When trimming up, care must be taken not to
exceed the converter‘s maximum allowable output
power.
To trim down the output voltage, a trim resistor,
RT-DECR, should be connected between TRIM (Pin
6) and SENSE(-) (Pin 5), as illustrated in Figure 2.
Figure 2. Output Voltage Trim-down
The trip-down resistor can be calculated from:
510
RT-DECR =
____________ - 10.2 [K]
where,
RT-DECR Required value of trim-down resistor
and is as defined above.