AT1382A
Preliminary Product Information
4-Channel DC-DC Converter for DSC
7. Setting time constant for Time-latch Short-circuit protection
The SCP comparator detects each channel output voltage while the power converter work at
normal condition. Q1 is turn on, and the voltage level of CSCP pin is held at low level. If the load
of one channel rapidly due to a short of the load, causing the output voltage to drop, the SCP
comparator output on that channel goes to "H" level. The transistor Q1 to be turned off and the
external capacitor CSCP to be charged at 1.0μA. The time period of short circuit protection as show
below equation.
tPE(s): Short detection time
tPE (s) = 0.7 * CSCP (μF)
When the CSCP is charged to the 0.7V, the timer-latch is set and output is turn off (dead time is set to 100
﹪). At this point, the timer-latch is closed and the CSCP terminal is held at "L" level. It could be
disabled short circuit protection function by connecting CSCP pin into the ground.
2F, No.10, Prosperity RD. II, Science-Based Industrial Park, Hsinchu 300,Taiwan, R.O.C.
Tel: 886-3-563-0878
Fax: 886-3-563-0879
WWW: http://www.aimtron.com.tw
Email: service@aimtron.com.tw
16
AIMTRON [ AIMTRON TECHNOLOGY ]
