I have a 200V boost converter here that is powering a pulsed load (ie. the actual load is much higher current than what the converter can supply so I'm charging capacitors during the off-time). The boost converter needs a minimum load though, but the current output is so low I don't really want to waste current through a minimum load resistor if it could be better used to charging the capacitors more quickly.
Can I use a 200V zener diode as the minimum load instead so that if the charging capacitors ever do reach max voltage then the zener turns on to stop the converter from surging? The zener can easily handle the maximum output current of the converter without the need for a resistor to drop the extra voltage across. Or is the zener not fast enough (or is the current is too low for the zener to effectively do it's job of clamping).
Zener - 1SMB5956BT3G (https://www.electro-tech-online.com/custompdfs/2007/12/1SMB5913BT3-DPDF.pdf)
Converter Voltage 200V, 6.25mA maximum, 10% load at all times
Also if the zener ever does turn on, it will completely drain the charge that has been built up on the capacitor right? THat's not such a good thing though I guess I could always add a diode to stop the capacitor from discharging through the zener. But the loss of the 10% load resistor might not have a very noticeable effect (but I am not sure) to warrant an extra zener and switching diode in place of a simple load resistor.
Can I use a 200V zener diode as the minimum load instead so that if the charging capacitors ever do reach max voltage then the zener turns on to stop the converter from surging? The zener can easily handle the maximum output current of the converter without the need for a resistor to drop the extra voltage across. Or is the zener not fast enough (or is the current is too low for the zener to effectively do it's job of clamping).
Zener - 1SMB5956BT3G (https://www.electro-tech-online.com/custompdfs/2007/12/1SMB5913BT3-DPDF.pdf)
Converter Voltage 200V, 6.25mA maximum, 10% load at all times
Also if the zener ever does turn on, it will completely drain the charge that has been built up on the capacitor right? THat's not such a good thing though I guess I could always add a diode to stop the capacitor from discharging through the zener. But the loss of the 10% load resistor might not have a very noticeable effect (but I am not sure) to warrant an extra zener and switching diode in place of a simple load resistor.
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