Stmicroelectronics S.r.l.

Stmicroelectronics International N.v.

Giuseppe Calderoni

Stefano Ramorini

Marco Attanasio

A load is powered between positive and negative rails. A switching converter generates the negative rail voltage based on an input voltage, with a power transistor involved therein. A replica generator produces a replica voltage mirroring the drain-to-source voltage of the power transistor. A buffer buffers the replica voltage. A first switch selectively connects the buffered voltage to an output node, in response to a control signal with a duty-cycle proportional to the input voltage divided by the negative rail voltage. A second switch selectively connects the buffered voltage to ground, according to the inverse of the control signal, resulting in a PWM signal at the output node. An output filter filters the PWM signal to generate a sense voltage indicative of the output current flowing from the load device. A processing circuit determines the input current from the positive rail to the load device based on the sense voltage.

Time modulation for DC-DC analog current sensing

A multiphase DC-DC converter has two converter arrangements, each with a switching stage that has a switching node, an inductor, a converter output node, a high-side switch, and a low-side switch. Current sensing circuits detect the instantaneous current flowing through either the high-side or low-side switches, and signal time-averaging circuits produce time-averaged signals indicating the average current during a switch conduction interval. The time-averaged signals are added up and re-scaled based on the time period of the switching nodes' electrical coupling to the converter output nodes to generate an output signal for the average output current.

Multiphase DC-DC switching converter circuit, corresponding power management integrated circuit and display device

A first node of converter circuit receives an input, provides an output at a second node, and has a third node coupled by an inductance to ground. A first switch has a current path between the first and third nodes and a second switch has a current path between the third and second nodes. The converter circuit operates in a first state (with the first switch conductive and the second switch non-conductive) and a second state (with the first switch non-conductive and the second switch conductive). Current flowing through the first switch is sensed during the first state to produce a sensing signal indicative of inductance current. The sensing signal is averaged to produce an averaged sensing signal indicative of an average value of the current. The averaged sensing signal is then weighted by a time during which the second switch is conductive to produce a weighted signal.

Growing community of inventors

Catania, Italy

Giuseppe Calderoni