Microchip Technology Inc.

Brian Dellacroce

James B Nolan

Hung Q Nguyen

Russell E Cooper

A semiconductor device for receiving analog input signals includes a microprocessor for processing signal information. The microprocessor is put in a sleep mode when not called upon to process signal information, and is either left in that mode or awakened depending on the level of a continuously variable analog input signal relative to a programmed threshold level. If the relative levels of the analog input signal and the programmed threshold level result in the microprocessor being awakened, information contained in the analog input signal is processed to initiate a selected action. In typical applications, the semiconductor device performs a control function, such as to control the operation of an external circuit in response to information from at least one continuously variable analog input signal derived from the external circuit. The microprocessor, when awakened, assists in controlling the external circuit to restore that analog input signal to a predetermined level distinct from the threshold level. In some applications, such as for battery charging and monitoring, the device is responsive to a plurality of different continuously variable analog input signals derived from the external circuit and indicative of a specified circuit function thereof. These signals are applied to the device in interleaved sequence according to a priority that depends on their respective rates of variation. The specified circuit function of the external circuit such as the level of charge on a battery is monitored, and the degree of control exercised by the device over the external circuit such as halting a charging of the battery based on level of charge, is a function of the designated priority of the plurality of analog input signals.

Microcontroller wake-up function having an interleaving priority scheme

A microcontroller for use in battery charging and monitoring applications is disclosed. The microcontroller includes a microprocessor and various front-end analog circuitry such as a slope A/D converter and a multiplexer for allowing a plurality of analog input signals to be converted to corresponding digital counts indicative of signal level. The microcontroller also includes an I.sup.2 C interface for supporting a bi-directional two wire bus and data transmission protocol that is useful for serially communicating with other peripheral or microcontroller devices. By making use of the I.sup.2 C interface, the microcontroller can be programmed while in the end application circuit. Such a feature allows customers to manufacture boards with unprogrammed devices and then program the microcontroller just before shipping the product. This allows the most recent firmware or a custom firmware to be programmed.

Serial communication interface system having programmable

A microcontroller for use in battery charging and monitoring applications is disclosed. The microcontroller includes a microprocessor and various front-end analog circuitry including a slope A/D converter and a multiplexer for allowing a plurality of analog input signals to be converted to corresponding digital counts indicative of signal level. The slope A/D converter includes a digital-to-analog converter (DAC) for providing a programmable charging current to generate a voltage across a capacitor, a precision comparator having inputs for receiving a selected analog input and the capacitor voltage, a counter and a capture register. After a reset is performed, the capacitor is charged while the counter begins counting such that when the capacitor voltage exceeds the selected analog input voltage, the comparator switches logic states thereby causing the obtained count of the counter to be stored in the register. This stored count represents the time that it took for the capacitor to charge up and exceed the selected analog input voltage and corresponds to voltage measurement of the selected analog input.

Microcontroller with analog front-end for providing intelligent battery

A microcontroller for use in battery charging and monitoring applications is disclosed. The microcontroller includes a microprocessor and various front-end analog circuitry such as a slope A/D converter and a multiplexer for allowing a plurality of analog input signals to be converted to corresponding digital counts indicative of signal level. In order to make the measurements of the selected analog inputs more precise, the microcontroller uses a unique calibration procedure whereby selected parameters associated with the analog circuitry that are subject to variation are measured during test and corresponding calibration constants are calculated therefrom and stored in program memory. These stored calibration constants are subsequently used by the microprocessor in conjunction with the digital counts of the analog input signals for calculating a more precise measurement of the analog input signals.

Digital trimming of on-chip analog components

A microcontroller for use in battery charging and monitoring applications is disclosed. The microcontroller includes a microprocessor and various front-end analog circuitry including a slope A/D converter and a multiplexer for allowing a plurality of analog input signals to be converted to corresponding digital counts indicative of signal level. The microcontroller further includes an on-chip temperature sensor, used in conjunction with the A/D converter, to monitor the temperature of the microcontroller. The temperature sensor generates and uses a differential voltage that is obtained across the base-emitter functions of two compatible bipolar transistors having dissimilar emitter areas. This differential voltage is proportional to temperature and may be sampled by the A/D converter to obtain a digital count indicative of the temperature of the microcontroller.

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Sedona, AZ, United States of America

Brian Dellacroce