Hi there,
I've just started looking into current sense chips, in preparation for building a robot that navigates using no sensors apart from current sense resistors in series with the motors, and probably a LTC 2991 for the current sensing.
What I'm wondering is whether or not I should be protecting the current sense circuits with a diode in the same fashion I would protect a transistor. I'll be using a H Bridge, with the current sense resistor either between Vcc and the sources of the P channel FETs or between the source of the N Channel enable FET and gnd.
The LTC2991 can only handle input voltages of up to Vcc, which will be regulated 5v for it, but unregulated 7.4v for the motor. Obviously I need to attenuate the signal with voltage dividers, but do I need some kind of back EMF protection for the current sense resistor?
Thanks a lot,
Barnaby
I've just started looking into current sense chips, in preparation for building a robot that navigates using no sensors apart from current sense resistors in series with the motors, and probably a LTC 2991 for the current sensing.
What I'm wondering is whether or not I should be protecting the current sense circuits with a diode in the same fashion I would protect a transistor. I'll be using a H Bridge, with the current sense resistor either between Vcc and the sources of the P channel FETs or between the source of the N Channel enable FET and gnd.
The LTC2991 can only handle input voltages of up to Vcc, which will be regulated 5v for it, but unregulated 7.4v for the motor. Obviously I need to attenuate the signal with voltage dividers, but do I need some kind of back EMF protection for the current sense resistor?
Thanks a lot,
Barnaby