PQ60280FTA26 Datasheet, PDF (12/14 Pages) SynQor Worldwide Headquarters – Full-brick DC/DC Converter

Technical Specification
Input: 36-75 V
Output: 28 V
Current: 26 A
Package: Full-brick
PROTECTION FEATURES
Input Under-Voltage Lockout: The converter is designed to
turn off when the input voltage is too low, helping avoid an input
system instability problem, described in more detail in the appli-
cation note titled “Input System Instability”. The lockout circuitry
is a comparator with DC hysteresis. When the input voltage is ris-
ing, it must exceed the typical “Turn-On Voltage Threshold”
value* before the converter will turn on. Once the converter is
on, the input voltage must fall below the typical Turn-Off Voltage
Threshold value before the converter will turn off.
Output Current Limit: If the output current exceeds the
"Output DC Current Limit Inception" point*, then a fast linear cur-
rent limit controller will reduce the output voltage to maintain a
constant output current. There is no minimum operating output
voltage. The converter will run with low on-board power dissi-
pation down to zero output voltage. A redundant circuit will shut-
down the converter if the primary current limit fails.
Back-Drive Current Limit: If there is negative output current
of a magnitude larger than the "Back-Drive Current Limit while
Enabled" specification*, then a fast back-drive limit controller will
increase the output voltage to maintain a constant output current.
If this results in the output voltage exceeding the "Output Over-
Voltage Protection" threshold*, then the unit will shut down. The
full I-V output characteristic can be seen in Figure 19.
Output Over-Voltage Limit: If the voltage across the output
pins exceeds the “Output Over-Voltage Protection” threshold*,
the converter will immediately stop switching. This prevents dam-
age to the load circuit due to 1) excessive series resistance in out-
put current path from converter output pins to sense point, 2) a
release of a short-circuit condition, or 3) a release of a current
limit condition. Load capacitance determines exactly how high
the output voltage will rise in response to these conditions.
Over-Temperature Shutdown: A temperature sensor on the
converter senses the average temperature of the module. The
thermal shutdown circuit is designed to turn the converter off
when the temperature at the sensed location reaches the Over-
Temperature Shutdown value. It will allow the converter to turn on
again when the temperature of the sensed location falls by the
amount of the Over-Temperature Shutdown Restart Hysteresis
value.
Start-up Inhibit Period: If any protection feature causes the
converter to shut down, the converter will attempt to restart after
320ms (typical), the "Restart Inhibit Period".* On initial appli-
cation of input voltage, the first startup delay is about 200ms
from input voltage valid to unit output rising. With the on/off pin
set to enable the converter, the "Turn-On Time"* will increase by
only 2ms.
* See specifications page for details.
Product # PQ60280FTA26
Phone [phone]
www.synqor.com
Doc.# 005-2FT628P Rev. C
5/21/08
Page 12