4 Apr 2012

Sometimes when engineers are trying to decide on a suitable microcontroller for simple applications like LED display panel control and battery charging, they have a difficult time because many of the newer microcontrollers have so many features and modes of operation that would never be used in their system. And their long list of features doesn’t usually include extra circuitry designed for LED lighting applications, so an engineer would have to design with separate LED drive components.

The new PIC12F752 and PIC12FHV752 microcontrollers from Microchip have just been introduced for general purpose applications and includes several next generation analog and digital peripherals from the PIC mid-range architecture. This 8-pin chip would work well not only for general purpose applications, but would be a good choice for specific applications like LED lighting, ballast control, battery chargers, power supplies, and system control.

The main enhancements of this MCU are the 50mA drive capability of two of the I/O pins, 25mA capability in four other pins, two high performance comparators(down to 20 ns response time), and a Complementary Output Generator (COG) peripheral that provides non-overlapping complementary outputs with dead band, blanking, and phase control.

The COG also provides advance features like auto reset and auto shutdown. These features alone would eliminate many external components and simplify code for a wide range of applications. The PIC12F752 is optimized for lighting and power-supply applications as the 50mA drive and COG features in particular can provide efficient power supply conversion for applications like LED lighting and battery charging. This MCU would also be suitable for AC-to-DC or DC-to-DC conversion applications.

The device also includes 1.75 KB of self read-write program memory, which can be very useful when an application requires remote updates or needs to store system data or look up tables.

Additionally, the new MCUs feature 64B of RAM, a 4 channel on-chip 10-bit ADC, a 5-bit DAC, and a Capture-Compare PWM module. The 4 channel, 10-bit ADC can be used to implement various sensor and mTouch applications. The capture-compare PWM module can be used to implement a variety of motor control and lighting applications. The high-voltage version, the PIC12HV752, incorporates a shunt regulator that allows for connection to an application that has high voltage rails, without the need of an external regulator. The standby current of the PIC12F752 in the sleep mode is only 50 nA at 2V, and the operating current is 11 uA at 32 kHz, 2.0V, and 260 uA at 4 MHz, 2V.