The MC68HC908LB8 Microcontroller

•Dual channel high resolution PWM (HRP) with deadtime insertion and shutdown input to perform light control and dimming functions for ballasts. The outputs use frequency dithering to achieve a 3.9 ns output resolution.

•Dual channel pulse width modulator module to provide power factor correction capability

•7-channel, 8-bit successive approximation analog-to-digital converter (ADC)

•Comparator for power factor correction capability or for general-purpose use

•7-bit keyboard interrupt

•One 16-bit, 2-channel timer interface module with one output available on port pin (PTA6) for input capture and PWM

•17 general-purpose input/output (I/O) pins and one input-only pin

– Three shared with HRP module

– Three shared with PWM module

– Three shared with comparator

– Seven shared with ADC module (AD[0:6])

– One shared with timer channel 0

– Two shared with OSC1 and OSC2

– One shared with reset

– Seven shared with keyboard interrupt

– One input-only pin shared with external interrupt (IRQ)

•Available packages:

– 20-pin small outline integrated chip (SOIC) package

– 20-pin plastic dual in-line package (PDIP)

•On-chip programming firmware for use with host personal computer which does not require high voltage for entry

•System protection features:

– Optional computer operating properly (COP) reset

– Low-voltage reset

– Illegal opcode detection with reset

– Illegal address detection with reset

•Low-power design; fully static with stop and wait modes

•Standard low-power modes of operation:

– Wait mode

– Stop mode

•Master reset pin and power-on reset (POR)

•674 bytes of FLASH programming routines in read-only memory (ROM)

•Break module (BRK) to allow single breakpoint setting during in-circuit debugging

•Internal pullup on RST pin to reduce customer system cost

•Selectable pullups on ports A and C

– Selection on an individual port bit basis

– During output mode, pullups are disengaged

•High current 10 mA sink / 10 mA source capability on all port pins

Dimmable Light Ballast with Power Factor Correction, Rev. 1

Freescale Semiconductor

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Freescale Semiconductor M68HC08 manual MC68HC908LB8 Microcontroller
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M68HC08 specifications

Freescale Semiconductor, known for its innovative solutions in the field of embedded systems, developed the M68HC08 microcontroller family, which includes the MC68HC908QT2. This 8-bit microcontroller is engineered to meet the demands of diverse applications, including automotive, industrial, and consumer electronics.

The MC68HC908QT2 is designed around Freescale’s M68HC08 core, which is renowned for its efficient and reliable performance. This microcontroller integrates a powerful instruction set, enabling developers to create high-performance applications with relatively low power consumption. The device operates at a clock frequency of up to 3 MHz, which is adequate for various control tasks.

One of the key features of the MC68HC908QT2 is its memory architecture. It includes a 2 KB Flash memory for program storage, representing a significant advantage for developers requiring non-volatile memory. Additionally, it encompasses 128 bytes of EEPROM memory, allowing for data retention even after power loss. The microcontroller also has 256 bytes of RAM for efficient data manipulation during operation.

In terms of input/output capabilities, the MC68HC908QT2 supports a variety of interfacing options. The microcontroller features up to 20 general-purpose I/O pins for flexibility in connecting with peripheral devices. Additionally, it provides multiple analog-to-digital converters (ADC) and timers that facilitate efficient analog signal processing and precise control through timing functions.

The architecture of the MC68HC908QT2 also incorporates sophisticated on-chip peripherals, enhancing its functionality. These peripherals include PWM (Pulse Width Modulation) outputs, which are essential for applications requiring motor control and other precise duty cycle processes. The integrated watchdog timer ensures reliable operation by resetting the system in the event of an application failure.

Moreover, the MC68HC908QT2 is equipped with an efficient power management system, enabling operation in a low-power mode, ideal for battery-powered applications. This microcontroller is packaged in a compact 28-pin dual in-line package (DIP), making it suitable for space-constrained designs.

In summary, the Freescale Semiconductor MC68HC908QT2 microcontroller is distinguished by its robust performance, extensive memory options, and versatile I/O capabilities. Its advanced features, including built-in timers, ADC, and a power management system, make it an exceptional choice for developers seeking to implement reliable and efficient embedded solutions. With its comprehensive architecture, the MC68HC908QT2 remains a popular choice in the landscape of 8-bit microcontrollers.
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