K
kell
- Jan 1, 1970
- 0
I need a blocking diode and charging current sensing into the positive
terminal of a twelve volt battery. It occured to me that I could use a
mosfet as the blocking diode and bias it on during charging, with the
Rds serving as sense resistor... and the side benefit of eliminating a
wasteful power diode.
How accurate is the Rds listed in mosfet datasheets? They all seem to
have a number with one or two sig figs and no tolerance spec.
And important is the Rds temperature coefficient; supposed positive but
I have no idea of the magnitude.
Max charging current is ten amps in the application. If it works, I
may use the same circuit on a 35 amp charger.
terminal of a twelve volt battery. It occured to me that I could use a
mosfet as the blocking diode and bias it on during charging, with the
Rds serving as sense resistor... and the side benefit of eliminating a
wasteful power diode.
How accurate is the Rds listed in mosfet datasheets? They all seem to
have a number with one or two sig figs and no tolerance spec.
And important is the Rds temperature coefficient; supposed positive but
I have no idea of the magnitude.
Max charging current is ten amps in the application. If it works, I
may use the same circuit on a 35 amp charger.