A synchronous rectifier includes: an integrator configured to integrate a voltage across a secondary side winding of a transformer over an integral period having an expected zero integral value; a first comparator configured to detect an end of a demagnetization phase of the secondary side winding based on diode detection; and a digital circuit configured to adjust a channel gain of the synchronous rectifier based on an integration error at the end of the integral period, the integration error corresponding to the difference between the integrated voltage at the end of the integral period and the expected zero integral. Corresponding methods of gain tuning and a power converter are also described.

An exemplary air cushion inflation machine includes: a first terminal connected to a direct current input; a second terminal; a reference resistor powered by the direct current input; an op-amp; and a transistor. The first terminal of the op-amp is connected to a variable voltage source and the second terminal of the op-amp is connected to the reference resistor. The transistor has a base connected to an output of the op-amp, an emitter connected to the reference resistor, and a collector connected to a first terminal of a sealing band apparatus having first and second terminals. A meltable material placed between the first and second terminals is melted by resistance of current flowing between the first and second terminals. The variable voltage source changes voltage based on a voltage drop measured across the first and second terminals by a voltage measurement device and the constant current.

A voltage adjustment apparatus, a chip, a power source, and an electronic device. The apparatus comprises: a voltage input module, used for receiving an input voltage; a current determining module, electrically connected to the voltage input module and used for determining an adjustment current on the basis of the input voltage and a load current; a control module, electrically connected to the current determining module and used for outputting a control signal on the basis of the adjustment current; and a voltage output module, electrically connected to the voltage input module, the current determining module, and the control module, and being used for outputting a target voltage on the basis of the control signal and the input voltage.

An overcurrent detection device of the present disclosure has two charge storage circuits, a control module and a counter circuit. The control module controls and provides charge paths of the two charge storage circuits, so that the two charge storage circuits are charged by a reference current and a sensed current respectively, wherein the sensed current is generated by an output current of a low-dropout regulator. The counter circuit obtains a voltage of the charge storage circuit charged by the sensed current, and counts accordingly. When the counting of the counter circuit reaches a specific value, the counter circuit outputs an overcurrent detection signal. When the output current is an overcurrent, the counter circuit first counts to the specific value before the charge storage circuit which is charged by the reference current is charged to a specific voltage.

In examples, an apparatus includes a FET, first and second voltage-to-current circuits, a current selection circuit, and a comparator. The FET has first and second segments. The first segment has a first gate coupled to the first voltage-to-current circuit, a first source, and a first drain. The second segment has a second gate coupled to the second voltage-to-current circuit, a second source coupled to the first source, and a second drain coupled to the first drain. The current selection circuit has a current selection circuit output and first and second current selection inputs. The first current selection circuit input is coupled to the first voltage-to-current circuit. The second current selection circuit input is coupled to the second voltage-to-current circuit. The comparator has a comparator output and first and second comparator inputs, the first comparator input is coupled to the current selection circuit output.

In an embodiment, a voltage comparator includes: a first switch having a conduction terminal coupled to an internal node that is coupled to an output of the voltage comparator; a current source; a capacitor; and a second switch connected in parallel with the capacitor, wherein the current source, the capacitor, and the first switch are coupled in series.

An N-tap feedforward equalizer (FFE) comprises a set of N FFE taps coupled together in parallel, a filter coupled between the (N−1)th FFE tap and the Nth FFE tap, and a summer coupled to an output of the set of N FFE taps. Each FFE tap includes a unique sample-an-hold (S/H) circuit that generates a unique time-delayed signal and a unique transconductance stage that generates a unique transconductance output based on the unique time-delayed signal. The filter causes the N-tap FFE to have the behavior of greater than N taps. In some examples, the filter is a first order high pass filter that causes coefficients greater than N to have an opposite polarity of the Nth coefficient. In some examples, the filter is a first order low pass filter that causes coefficients greater than N to have the same polarity as the Nth coefficient.

A voltage-to-current converter includes a first transistor having a drain coupled to a first node, a second transistor having a drain coupled to the first node, an operational amplifier having a first input terminal configured to receive a reference voltage and a second input terminal coupled to a source of the first transistor or a source of the second transistor, a control circuit having an input terminal coupled to an output terminal of the operational amplifier, a first output terminal coupled to a gate of the first transistor, and a second output terminal coupled to a gate of the second transistor, a first resistor coupled between the source of the first transistor and a ground, and a second resistor coupled between the source of the second transistor and the ground. An output current of the voltage-to-current converter is generated from the first node.

An electronic circuit is provided. The electronic circuit includes a first current generating circuit configured to output a first operating current based on a first operating voltage; and an input circuit configured to: receive a first current corresponding to a first input voltage and a second current corresponding to a second input voltage, wherein the first current and the second current are based on the first operating current; receive a third current and a fourth current that are generated based on the first operating voltage; and generate a fifth current corresponding to the second input voltage based on a second operating current. The electronic circuit is configured to generate an output voltage that is associated with a difference between the first input voltage and the second input voltage based on the second current, the fourth current and the fifth current, and the fourth current corresponds to the third current.

An environmental energy harvesting device comprises: an energy converting element that converts environmental energy into electric energy; an environmental sensor that is disposed in an identical environment as the energy converting element; and a power supply circuit that receives electricity converted into by the energy converting element and outputs the electricity to an outside. The power supply circuit changes an operation condition in accordance with an output of the environmental sensor.