Active rectification and battery protection circuit

An active rectification circuit comprising:

• a) an amplifier element coupled to a voltage source;
• and
• a body-diode-free transistor element, said transistor element being a MOSFET and having a gate terminal coupled to an output of said amplifier element, wherein said MOSFET is coupled to an input of said amplifier, said output is couplable to a reversible current source, and said amplifier is designed to switch said MOSFET on or off as a function of a current from said current source.
• wherein said MOSFET acts as a rectifier to rectify an input signal, said amplifier element automatically controls said MOSFET in response to a predetermined condition of said signal, and wherein said MOSFET has four terminals including a source terminal, a bulk terminal, a drain terminal, and said gate terminal, wherein said source terminal and said body terminal serve as an anode of said rectifier, and wherein said drain terminal serves as a cathode of said rectifier.

An active rectification circuit, said circuit comprising:

• a) a difference amplifier, said difference amplifier being coupled to a current mirror designed to modify the gain of said difference amplifier;
• and
• b) a body-diode-free transistor element, said transistor element being a MOSFET pair,
• wherein said difference amplifier automatically controls said transistor element in response to a predetermined condition of a signal.

A method of rectifying a reversible current comprising the steps of:

• a) coupling a pair of MOSFETs to said reversible current;
• b) coupling a difference amplifier to a control node of said pair of MOSFETs;
• c) supplying a biasing reference voltage to a difference amplifier by coupling a first bipolar transistor to a noninverting terminal of said difference amplifier, and
• coupling a second bipolar transistor to an inverting terminal of said difference amplifier, so as to define a threshold potential for operation of said pair of MOSFETs,
• wherein a current density of said first bipolar transistor is greater than a current density of said second bipolar transistor.