Sounds like I can use a Schottky diode. I found one with a voltage
drop of about a half a volt. My chips downstream appear to be able to
handle that drop. I suppose I'll have some adjustment of the 5V at
the power supply too. If I can crank it as high as 5.5V I might be
able to compensate.
Re: Circuit ideas for undervoltage protection? ... Look in the link below for "Circuit Protects FPGAs From killer Spikes", ... The forward voltage drop is heavily depending on the ... > Only very few schottky diodes guarantee Vfw values of less than 0.3 Volt... > qualities of a schottky diode that seem to be incompatible. ... (sci.electronics.components)
Re: Circuit ideas for undervoltage protection? ... >For most standard integrated circuits manufacturers rate the min/max ... The forward voltage drop is heavily depending ... >Only very few schottky diodes guarantee Vfw values of less than 0.3 Volt... >qualities of a schottky diode that seem to be incompatible. ... (sci.electronics.design)
Re: Circuit ideas for undervoltage protection? ... I think the out pin is a high impeadant pin used for regulating the current. ... For most standard integrated circuits manufacturers rate the min/max voltage levels at the pins with something like -0.3V to Vcc + 0.3V, which is probably derived from the idea of having schottky diodes, either internal or external, clamping the pin to the above levels. ... Which seems so obvious proves problematic when taking a closer look at various schottky diode datasheets.... The forward voltage drop is heavily depending on the forward current which can easily result in voltage drops of more than 1 volt. ... (sci.electronics.design)
Circuit ideas for undervoltage protection? ... For most standard integrated circuits manufacturers rate the min/max voltage levels at the pins with something like -0.3V to Vcc + 0.3V, which is probably derived from the idea of having schottky diodes, either internal or external, clamping the pin to the above levels. ... Which seems so obvious proves problematic when taking a closer look at various schottky diode datasheets.... The forward voltage drop is heavily depending on the forward current which can easily result in voltage drops of more than 1 volt. ... (sci.electronics.design)
Circuit ideas for undervoltage protection? ... For most standard integrated circuits manufacturers rate the min/max voltage levels at the pins with something like -0.3V to Vcc + 0.3V, which is probably derived from the idea of having schottky diodes, either internal or external, clamping the pin to the above levels. ... Which seems so obvious proves problematic when taking a closer look at various schottky diode datasheets.... The forward voltage drop is heavily depending on the forward current which can easily result in voltage drops of more than 1 volt. ... (sci.electronics.components)
