ZY7120L-T2 POWER ONE, ZY7120L-T2 Datasheet - Page 18

• Manufacturer Part Number: ZY7120L-T2
• Description: Module DC-DC 1-OUT 0.5V to 5.5V 20A 25-Pin SMT T/R
• Manufacturer: POWER ONE
• Type: Step Downr

Specifications of ZY7120L-T2

• Package: 25SMT
• Output Current: 20 A
• Output Voltage: 0.5 to 5.5 V
• Input Voltage: 3 to 13.2 V
• Number Of Outputs: 1

8.1.1
The output voltage programming range is from 0.5V
to 5.5V. Within this range, there are 256 predefined
voltage setpoints.
output voltage settings, the voltage range is divided
into three sub-ranges as shown in Table 2.
8.1.2
If the output voltage needs to be varied by a certain
percentage, the margining function can be utilized.
The margining can be programmed in the GUI
Output Configuration window or directly via the I
bus using high level commands as described in the
‘”DPM Programming Manual”.
In order to properly margin POLs that are connected
in parallel, the POLs must be members of one of the
Parallel Buses.
Configuration Window shown in Figure 55.
8.1.3
Optimal voltage positioning increases the voltage
regulation window by properly positioning the output
voltage setpoint. Positioning is determined by the
load regulation that can be programmed in the GUI
Output Configuration window shown in Figure 27 or
directly via the I
register shown in Figure 38.
Figure 29 illustrates optimal voltage positioning
concept. If no load regulation is programmed, the
headroom (voltage differential between the output
voltage
approximately half of the voltage regulation window.
When load regulation is programmed, the output
voltage
increases, so the VI characteristic will have a
negative slope. Therefore, by properly selecting the
operating point, it is possible to increase the
headroom as shown in the picture.
ZD-00194 Rev. 2.5, 01-Jul-10
V
OUT MIN
0.500
2.025
Table 2. Output Voltage Adjustment Resolution
5.3
will
Output Voltage Setpoint
Output Voltage Margining
Optimal Voltage Positioning
setpoint
, V
decrease
2
C bus by writing into the CLS
and
To improve resolution of the
V
Refer to the
OUT MAX
2.000
5.25
5.5
as
a
, V
regulation
the
output
Resolution, mV
GUI System
www.power-one.com
12.5
25
50
limit)
ZY7120 20A DC-DC Intelligent POL Data Sheet
current
2
C
is
3V to 13.2V Input
Increased headroom allows tolerating larger voltage
deviations. For example, the step load change from
light to heavy load will cause the output voltage to
drop. If the optimal voltage positioning is utilized, the
output voltage will stay within the regulation window.
Otherwise, the output voltage will drop below the
lower regulation limit. To compensate for the voltage
drop external output capacitance will need to be
added, thus increasing cost and complexity of the
system.
The effect of optimal voltage positioning is shown in
Figure 30 and Figure 31.
output load causes large peak-to-peak deviation of
the output voltage. By programming load regulation,
the peak to peak deviation is dramatically reduced.
Figure 30. Transient Response without Optimal Voltage
Upper Regulation
Lower Regulation
Limit
Limit
Figure 29. Concept of Optimal Voltage Positioning
V
OUT
Positioning
Load Regulation
Headroom with
Light
Load
Headroom without
Load Regulation

0.5V to 5.5V Output
Operating
I
OUT
Point
In this case, switching
Load Regulation
VI Curve With
Page 18 of 34
VI Curve Without
Load Regulation
Heavy
Load