dsPIC33F Digital Signal Controllers (DSCs)
Microchip's dsPIC33F Digital Signal Controller (DSC) family is built around a base architecture and instruction set in common with the 16-bit controller families while adding full Digital Signal Processing (DSP) capabilities.
The dsPIC33F DSC family offers the following features:
- 16-bit data, 24-bit wide instructions
- Up to 60 MIPS at 3.3 V
- 3.0 to 3.6 V operation
- -40 °C to 85 °C (extended temperature planned)
- Data EEPROM emulation in program Flash
- 64 to 100 pin packages
- Up to 15 channel Direct Memory Access (DMA)
- Timers/Capture/Compare/Pulse-Width Modulation (PWM)
- Motor control peripherals
- Analog-to-Digital Converters (ADCs)
- Communication modules
- Power management
- Switch between clock sources in real-time
- Programmable power-on reset start-up
- Programmable low-voltage detect
- Programmable brown-out reset
- Idle and Sleep modes with fast wake-up
In addition to the above features, dsPIC33 devices offer a specialized Switch Mode Power Supply (SMPS) peripheral. See the figure below.
dsPIC33F SMPS Comparator
The dsPIC33F SMPS comparator module monitors current and/or voltage transients that may be too fast for the CPU and ADC to capture. The SMPS comparator module contains the following major features:
- 16 selectable comparator inputs
- Up to four analog comparators
- 10-bit Digital-to-Analog Converters (DAC) for each analog comparator
- Programmable output polarity
- Interrupt generation capability
- DACOUT pin to provide DAC output
- DAC has three ranges of operation:
- AVDD/2
- Internal Reference (INTREF)
- External Reference (EXTREF)
- ADC sample and convert trigger capability
- Disable capability reduces power consumption
- Functional support for PWM module:
- PWM duty-cycle control
- PWM period control
- PWM fault detect
The figure below shows a functional block diagram of one analog comparator from the SMPS comparator module. The analog comparator provides high-speed operation with a typical delay of 20 ns. The comparator has a typical offset voltage of ±5 mV. The negative input of the comparator is always connected to the DAC circuit. The positive input of the comparator is connected to an analog multiplexer that selects the desired source pin. The analog comparator input pins are typically shared with pins used by the ADC module. Both the comparator and the ADC can use the same pins at the same time. This capability enables you to measure an input voltage with the ADC and detect voltage transients with the comparator.