Patent ID: 9722420
Date: 2017-08-01
CPC Classifications: H02J

Claim:
1. A circuit comprising: a photovoltaic cell; a first resistor coupled to the photovoltaic cell; a second resistor having a first lead coupled to the first resistor and a second lead coupled to ground; a third resistor having a first lead coupled to the first resistor and the second resistor; an integrator having a first input coupled to the third resistor and a second input coupled to a reference voltage; a capacitor having a first lead coupled to the first input of the integrator and a second lead coupled to an output of the integrator; a first transistor having a control terminal coupled to the output of the integrator, a first conducting terminal coupled to a current source and a second conducting terminal coupled to a fourth resistor; a second transistor having a control terminal and a first conducting terminal coupled to the first conducting terminal of the first transistor and a second conducting terminal coupled to ground; a third transistor having a control terminal coupled to the control terminal of the second transistor, a first conducting terminal coupled to ground and a second conducting terminal coupled to an operational amplifier; a fourth transistor having a first conducting terminal coupled to the current source and a second conducting terminal coupled to the operational amplifier; a fifth transistor having a first conducting terminal coupled to the current source, a second conducting terminal coupled to the operational amplifier and a control terminal coupled to a control terminal of the fourth transistor; and a diode coupled to the operational amplifier and the fifth transistor.