YNC12S20 Datasheet, PDF (6/28 Pages) Power-One – 9.6-14 VDC Input; 0.7525-5.5 VDC Programmable 20 A

YNC12S20 DC-DC Converter Data Sheet
9.6-14 VDC Input; 0.7525-5.5 VDC Programmable @ 20 A
Vin
Nex^TM-c Series
SENSE
Converter
(Top View)
Rw
ON/OFF
Vout
Vin
GND
TRIM
Rload
Rw
Fig. B: Remote sense circuit configuration.
Because the sense lead carries minimal current,
large traces on the end-user board are not
required. However, sense traces should be
located close to a ground plane to minimize
system noise and ensure optimum performance.
When utilizing the remote sense feature, care
must be taken not to exceed the maximum
allowable output power capability of the converter,
equal to the product of the nominal output voltage
and the allowable output current for the given
conditions.
When using remote sense, the output voltage at
the converter can be increased up to 0.5V above
the nominal rating in order to maintain the required
voltage across the load. Therefore, the designer
must, if necessary, decrease the maximum current
(originally obtained from the derating curves) by
the same percentage to ensure the converter’s
actual output power remains at or below the
maximum allowable output power.
Output Voltage Programming (Pin 3)
The output voltage can be programmed from
0.7525V to 5.5V by connecting an external resistor
between TRIM pin (Pin 3) and GND pin (Pin 5);
see Fig. C.
A trim resistor, R_TRIM, for a desired output voltage
can be calculated using the following equation:
RTRIM =
10.5
−1
(VO-REQ - 0.7525)
[kΩ]
where,
RTRIM = Required value of trim resistor [kΩ]
VO−REQ = Desired (trimmed) output voltage [V]
Vin
Nex^TM-c Series
SENSE
Converter
ON/OFF
(Top View)
Vout
Vin
GND
TRIM
Rload
R_TRIM
Fig. C: Configuration for programming output voltage.
Note that the tolerance of a trim resistor directly
affects the output voltage tolerance. It is
recommended to use standard 1% or 0.5%
resistors; for tighter tolerance, two resistors in
parallel are recommended rather than one
standard value from Table 1.
The ground pin of the trim resistor should be
connected directly to the converter GND pin (Pin
5) with no voltage drop in between. Table 1
provides the trim resistor values for popular output
voltages.
Table 1: Trim Resistor Value
V_0-REG [V]
R_TRIM [kΩ]
The Closest
Standard Value [kΩ]
0.7525
open
1.0
41.2
41.2
1.2
22.46
22.6
1.5
13.0
13.0
1.8
9.0
9.09
2.0
7.4
7.32
2.5
5.0
4.99
3.3
3.12
3.09
5.0
1.47
1.47
5.5
1.21
1.21
The output voltage can be also programmed by
external voltage source. To make trimming less
sensitive, a series external resistor Rext is
recommended between the TRIM pin and the
programming voltage source. Control Voltage can
be calculated by the formula:
VCTRL = 0.7 − ^{(1+ REXT)(VO-REQ - 0.7525)}
[V]
15
where,
OCT 12, 2006 revised to APR 23, 2007
Page 6 of 28
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