S7KS-25D Datasheet, PDF (3/4 Pages) Bel Fuse Inc. – NON-ISOLATED DC/DC CONVERTERS

NON-ISOLATED DC/DC CONVERTERS
3 –15V Input / Programmable Output / 25A
Feature Descriptions
Remote Sense
These modules employ double-ended remote
sense. The +Sense lead should be connected to
Vout at the desired point of regulation (typically as
close to the load as possible). Similarly, the –
Sense lead should be connected to Gnd at the
desired point of regulation. If the Sense feature is
not being used, these signals should be connected
to Vout and Gnd at the module.
Voltage Programming
The output voltage may be digitally programmed
with a 6-bit word to any voltage from 0.7V (000000)
to 5.4V (111111). When the most significant bit
(MSB) is 0 the resolution is 50mV per step. When
the MSB toggles to 1, the resolution becomes
100mV per step.
Analog Trim
An analog trim pin may be used to margin the
output voltage up or down 10% for any give digitally
programmed set point.
Vpp / Reset
This pin is used in the factory to program the
embedded micro-controller.
Power Good
The PwrGood pin is an open drain signal that is
pulled low whenever the output voltage is within
10% of its expected voltage. The maximum pull-up
voltage for this signal is 7V. Typically it would be
pulled high to a 3.3V or 5V rail.
Bias Voltage
This pin supplies voltage to the micro-controller and
to the multi-chip module. If the source voltage is 5V
then Vin and Vbias may be tied together. If the
source voltage is lower or higher than the 5V
requirement for the bias voltage then this pins
should be connected to a source capable of
supplying at least 200mA.
Load Sharing
When the outputs and the I share pins of multiple
modules are tied together, the units will share the
load to within 2A.
Auto-Phasing
When multiple Keystone modules are used on
the same board they may be connected together
in a such a way that they operate as a single
multiphase unit. Each of the CLK signals should
be tied together in a star connection. The A
signal of the first unit should be left floating. The
B signal of the each unit should be connected to
the A signal of the following unit. The B signal of
the last unit should be grounded.
Regardless of whether or not the units are of the
same output voltage and/or whether or not they
are load sharing, the units may still be
autophased to provide for input ripple current
cancellation.
Efficiency
Vin = 5V
98.0
96.0
94.0
92.0
90.0
88.0
86.0
84.0
82.0
5A 10A 15A 20A 25A
3.3V
1.8V
Vin = 12V
96.0
94.0
92.0
90.0
88.0
86.0
84.0
82.0
80.0
5A 10A 15A 20A 25A
3.3V
1.8V
Bel Fuse Inc. 206 Van Vorst Street, Jersey City, NJ 07302 • Tel [phone] • Fax [phone] • www.belfuse.com