Application Notes
CoolConverter™ Family
Galaxy’s COOLCONVERTERS™ feature:
• Single-stage power conversion architecture, control, and
magnetic design allow unprecedented power density and
efficiency in an isolated power supply.
• An advanced microcontroller reduces parts count while
adding features, performance, and flexibility in the design.
Protection and Control
Valid Input Voltage Range:
Undervoltage Hysteresis
60
50
40
30
20
10
0
The converter measures the input voltage and will
not allow operation outside of the input voltage
specification. As shown by the graphs, hysteresis is
added to both the high and low voltage to prevent
the converter from turning on and off repeatedly
when the voltage is held near either voltage extreme.
At low line this assures the maximum input current is
not exceeded; at high line this assures the semicon-
ductor devices in the converter are not damaged by
excessive voltage stress.
0Aout
5Aout
33
34
35
36
37
Input Voltage (V)
ON/OFF Logic Option:
The ON/OFF control logic can be either Negative
(standard) or Positive to enable the converter. For
Negative logic, bring the ON/OFF pin to less than
1.0V with respect to the –INPUT pin to enable the
converter. The pull-down must be able to sink
100µA. For Positive logic, bring the ON/OFF pin to
greater than 4.0V with respect to the –INPUT pin
and be limited to less than 10V. To request the
Positive logic version, add the suffix (P) to the stan-
dard part number. The ON/OFF pin has a built-in pull
up resistor of approximately 100kΩ to +5V.
Overvoltage Hysteresis
60
50
40
30
20
10
0
0Aout
5Aout
54
54.5
55
55.5
56
56.5
57
Input Voltage (V)
Part No. 02-GHB-03 Rev. 0.94– 031605
WWW.GALAXYPWR.COM
GHBW53V08 – 3
Galaxy Power Inc. 155 Flanders Road Westborough, MA 01581 Telephone: 508-870-9775 Fax: 508-870-9796 e-mail: info@galaxypwr.com