
MCD10206 Rev. 1.0, 24-Jun-10
Page 6 of 27
www.power-one.com
YS12S10 DC-DC Converter Data Sheet
9.6-14 VDC Input; 0.7525-5.5 VDC Programmable @ 10 A
Because the sense lead carries minimal current,
large traces on the end-user board are not required.
However, sense trace should be located close to a
ground plane to minimize system noise and ensure
the optimum performance.
When utilizing the remote sense feature, care must
be taken not to exceed the maximum allowable
output power capability of the converter which is
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 0.5 V 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
0.7525 to 5.5 V by connecting an external resistor
between TRIM pin (Pin 3) and GND pin (Pin 5); see
Fig. C. Note that when trim resistor is not connected,
output voltage of the converter is 0.7525 V.
A trim resistor, RTRIM, for a desired output voltage
can be calculated using the following equation:
1
0.7525)
-
(V
5
.
10
R
REQ
-
O
RIM
T
[k]
where,
TRIM
R
Required value of trim resistor [k]
REQ
O
V
Desired (trimmed) output voltage [V]
Rload
Vin
R T-INCR
Converter
Vin
GND
ON/OFF
SENSE
(Top View)
TRIM
Vout
Y-Series
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
V0-REG [V]
RTRIM [k]
The Closest
Standard Value [k]
0.7525
open
1.0
41.42
41.2
1.2
22.46
22.6
1.5
13.05
13.0
1.8
9.02
9.09
2.0
7.42
7.50
2.5
5.01
4.99
3.3
3.12
3.09
5.0
1.47
5.5
1.21
The output voltage can also be programmed by
external voltage source. To make trimming less
sensitive, a series external resistor REXT is
recommended between TRIM pin and programming
voltage source. Control Voltage can be calculated by
the formula:
15
0.7525)
-
)(V
R
1
(
7
.
0
V
REQ
-
O
EXT
CTRL
[V]
where
CTRL
V
Control voltage [V]
EXT
R
External resistor between TRIM pin and
voltage source; the k value can be chosen
depending on the required output voltage range.
Control voltages with
EXT
R
0 and
EXT
R
15 k are
shown in Table 2.
Table 2: Control Voltage [VDC]
V0-REG [V]
VCTRL (REXT = 0)
VCTRL(REXT = 15 k)
0.7525
0.700
1.0
0.684
0.436
1.2
0.670
0.223
1.5
0.650
-0.097
1.8
0.630
-0.417
2.0
0.617
-0.631
2.5
0.584
-1.164
3.3
0.530
-2.017
5.0
0.417
-3.831
5.5
0.384
-4.364