Abstract: A controller (10) for a constant frequency current-mode buck-boost converter, the converter including an inductor (L), a first switch (SW1, S1) connected between an input terminal (Vin) of the converter and one end of the inductor (L), a diode or a switch (D1, S2), connected between the first end of the inductor and ground, a second diode or switch (D2, S3) connected between a second end of the inductor and an output terminal (Vout) of the converter, and a second switch (SW2, S4) coupled between the other end of the inductor and ground. A current sensor is also present for sensing current in the first switch (SW1, S1) as a measure of the inductor (L) current. The controller (10) comprises a feedback circuit for deriving a feedback signal from the output terminal (Vout) and a waveform generator (31, 32) for generating buck and boost slope compensation ramps (RMP-BUCK, RMP-BOOST) used for improving stability of operation in both buck and boost operating modes of the converter.

Abstract: An apparatus and a method for charging and for charge monitoring of a rechargeable battery. A charging circuit contains a rechargeable battery (B) and a charging device (L) for charging the rechargeable battery. A measurement device (M) is arranged in the charging circuit and contains a device for determining the rechargeable-battery current and the state of charge of the rechargeable battery. A control device (R) compares a value that is proportional to the rechargeable-battery current with a set value, and controls the charging device.

Abstract: A reliable start-up circuit for starting a bandgap type voltage reference generator which ensures that the bandgap reference cell will operate at a stable operating point before the start-up circuit is disabled.

Abstract: According to the suggested principle, a comparator (9) is provided in an integrated circuit (1), which reads out an externally attachable component (4) and compares the value with the value of a reference component (6). The comparison result is forwarded to a control unit (12) which addresses at least one function block (13a, 13b) of the integrated circuit arrangement (1) depending on the comparison result. Accordingly, the mode of operation of the chip (1) is determined by the value (Rprog) of the externally attachable component (4) and/or is programmed thereby. The suggested principle is applicable, for example, with Power Management Units.

Abstract: A current sensing circuit for sensing the current through a main switch, such as the PMOS or NMOS switches of a switching regulator, is disclosed. The circuit includes a mirror switch, said mirror switch being substantially similar to said main switch but with a smaller aspect ratio, a difference amplifier for ensuring that the voltage across said first leg and across said second leg are substantially equal and thereby to derive from said mirror switch a sensing current nominally equal to a current flowing in said main switch divided by a sensing ratio, a current source for producing a quiescent current in said difference amplifier and a compensatory device for compensating for said quiescent current such that said current sensing circuit can sense currents in the main switch which are smaller than the quiescent current multiplied by the sensing ratio. The compensatory device may be one or two switches essentially similar to the mirror switch.

Abstract: A current-mode switching regulator including at least: an inductor; a main switch for controlling the current flow through the inductor; and a feedback control circuit for operating the main switch cyclically and to vary a duty cycle of the main switch so as to substantially maintain an output voltage of the regulator at a desired level. The feedback control circuit further includes slope compensation circuitry adding slope compensation to a signal representing the inductor current prior to the slope compensated signal being compared to the fed-back output error voltage.

Abstract: A current sensing circuit for sensing the current through a main switch, such as the PMOS or NMOS switches of a switching regulator, is disclosed. The circuit comprises a mirror switch, said mirror switch being substantially similar to said main switch but with a smaller aspect ratio, a difference amplifier for ensuring that the voltage across said first leg and across said second leg are substantially equal and thereby to derive from said mirror switch a sensing current nominally equal to a current flowing in said main switch divided by a sensing ratio, a current source for producing a quiescent current in said difference amplifier and a compensatory device for compensating for said quiescent current such that said current sensing circuit can sense currents in the main switch which are smaller than the quiescent current multiplied by the sensing ratio. The compensatory device may be one or two switches essentially similar to the mirror switch.