Microcontroller with optimized ADC controller

摘要

An analog-to-digital (ADC) controller is used in combination with a digital processor of a microcontroller to control the operation of capacitance measurements using the capacitive voltage division (CVD) method. The ADC controller handles the CVD measurement process instead of the digital processor having to run additional program steps for controlling charging and discharging of a capacitive touch sensor and sample and hold capacitor, then coupling these two capacitors together, and measuring the resulting voltage charge thereon in determining the capacitance thereof. The ADC controller may be programmable and its programmable parameters stored in registers.

主权项

1. A microcontroller comprising:
a plurality of ports coupled with an analog bus through an analog multiplexer; an analog-to-digital converter (ADC) coupled with the analog bus, wherein the ADC comprises a sample and hold capacitor; and a sample and hold pull up/down circuit coupled with the sample and hold capacitor, wherein each one of the plurality of ports is programmable to operate as an analog input port, a digital input port or a digital output port and comprises a respective port pull up/down circuit.