Texas Instruments Incorporated Deutschland, Gmbh

Avago Technologies General IP (singapore) Pte. Ltd.

Marcin Kamil Augustyniak

Bernhard Wicht

Weng Fei Wong

Ingo Hehemann

Cheng Kwong Cheang

Kek Leong Yap

Aun Choon Chong

An optical encoder is disclosed. Specifically, a three-channel encoder is disclosed which utilizes a single track for all three channels. An index channel is provided on the same optical track as the first and second channels which are used to determine incremental angular position. Thus, a more compact and simple three-channel encoder is provided.

Single track three-channel encoder with differential index

Optical encoding system and optical encoder having an array of incremental photodiodes and an index photodiode for use in an optical encoding system

With conventional charge pumps, significant noise is present due at least in part to large changes in the supply current. To combat this problem, a charge pump is provided that includes a number of stages. These stages are coupled to receive periodic alternating voltages having a phase shift with respect to each other so that the changes in the supply current are reduced, which reduces noise.

Charge pump with self-timing and method

A linear voltage regulator is provided which has a pair of complementary power transistors connected 'back to back' in series between a voltage input and a voltage output. A current sense circuit including a current sense resistor is connected in parallel across one of the power transistors, such as the one connected to the voltage input. As long as the voltage drop in the current sense circuit remains small, i.e. less than app. 0.7V, the current flowing through the bulk diode of the power transistor remains negligible and the entire output current flows through the current sense circuit. For higher output currents the voltage drop across the current sense circuit is limited by the parallel bulk diode of the power transistor. The current sense resistor can be dimensioned to generate a relatively high voltage drop of e.g. 100 mV, and a high accuracy of open load detection is achieved without the requirement for a high precision comparator.

Linear voltage regulator with accurate open load detection

An electronic device includes an operational amplifier, with the operational amplifier having an amplifier input stage coupled with a first output node to an amplifier output stage. A compensation capacitance is connected between an output node of the amplifier output stage and the first output node of the amplifier input stage, thereby operating as a compensator for stabilizing the operational amplifier. The compensation capacitance provides a parasitic diode drawing a first leakage current from the first output node of the amplifier input stage, a leakage current compensation circuit being coupled to the first output node of the amplifier input stage and coupled to a second output node of the amplifier input stage for drawing a first current from the first output node and a second current from the second output node. The leakage current compensation circuit is adapted such that the second current is greater than the first current by an amount corresponding to the first leakage current.

Circuit for compensation of leakage current-induced offset in a single-ended op-amp

An integrated electronic device includes a sample and hold stage. The sample and hold stage has a sampling capacitor (C) for an input voltage at an input node (Vin), a first switch (S) coupled between the input node (Vin) and the sampling capacitor (C) for connecting the input node (Vin) to the sampling capacitor (C). There is also a voltage follower with an input coupled to the sampling capacitor (C). The first switch (S) includes a first MOS transistor (NM) coupled between the input node (Vin) and the sampling capacitor (C). The first MOS transistor has a bulk. The sample and hold stage is adapted to selectively couple the bulk to a node having a voltage level (V) which is equal or close to the voltage level at the input node of the voltage follower.

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Wuppertal, Germany

Marcin Kamil Augustyniak