ZY2160 60A No-Bus POL Data Sheet
8V to 14V Input
• 0.5V to 2.75V Output
ZD-01966 Rev. 1.3, 11-Oct-2011 www.power-one.com
Page 13 of 14
10. Application Information
10.1 Output Voltage Programming
Resistance of the trim resistor is determined from the
equation below:
,
)5.5(20
OUT
OUT
TRIM
V
V
R
−×
= kΩ
where V
OUT
is the desired output voltage in Volts.
If the R
TRIM
is open or the TRIM pin is shorted to
PGND, the V
OUT
=0.5V.
10.2 Output Voltage Margining
Margining can be implemented by changing the
resistance between the REF and TRIM pins.
Figure 12. Margining Configuration
In the schematic shown in Figure 12, the nominal
output voltage is set with the trim resistor R
TRIM
calculated from the equation in the paragraph 10.1.
Resistors R
UP
and R
DOWN
are added to margin the
output voltage up and down respectively and
determined from the equations below.
∆
∆−×
×
+
×
=
%
%5
20
20
V
VR
R
R
R
TRIM
TRIM
TRIM
UP
, kΩ
( )
∆−
∆
×+=
%100
%
20
V
V
RR
TRIMDOWN
, kΩ
where R
TRIM
is the value of the trim resistor in kΩ and
ΔV% is the absolute value of desired margining
expressed in percents of the nominal output voltage.
During normal operation the resistors are removed
from the circuit by the switches. The “Margining
Down” switch is normally closed shorting the resistor
R
DOWN
while the “Margining Up” switch is normally
open disconnecting the resistor R
UP
.
An alternative configuration of the margining circuit is
shown in Figure 13. In the configuration both
switches are normally open that may be
advantageous in some implementations.
Figure 13. Alternative Margining Configuration
R
UP
and R
DOWN
for this configuration are determined
from the following equations:
∆
∆−×
×
+
×
=
%
%5
20
20
V
V
R
R
R
R
TRIM
TRIM
TRIM
UP
, kΩ
∆
∆
−
×
+
×
=
%
%100
20
20
V
V
R
R
R
TRIM
TRIM
DOWN
, kΩ
Caution: Noise injected into the TRIM node may affect accuracy
of the output voltage and stability of the POL
converter. Always minimize the PCB trace length from
the TRIM pin to external components to avoid noise
pickup.
Refer to No-Bus
TM
POL Converters. Application
Note on
www.power-one.com for more application
information on this and other product features.
