Reduced Power Modes

The power consumed during sleep when the RTO oscillator is left running is greater than the power consumed during sleep when the CRO oscillator is left running.

If the idle state clock control is clear, then the PLL circuitry, active during sleep, will attempt to regulate the MC to whatever frequency is programmed in the PLL multiplier (see Section 2.9.3, Clock Speed Control Register). The MC con- tinues to run at this frequency, even during sleep, provided that the reference oscillator is enabled.

If the idle state clock control is set, then neither the MC, CPU clock, nor the TIMER clocks run during sleep, unless the TIMER source is linked to the reference oscillator (Section 2.8, Time Registers). These relationships are shown explicitly, as a function of the reduced power mode, in Table 2±4.

Because the DAC circuitry is the single most source of power consumed on the C614, it is important to disable the DAC entirely before engaging any IDLE instruction. This is accomplished at the DAC control register, address 0x34. Refer to Section 3.2.2, DAC Control and Data Registers.

The ARM bit is another important control to consider before engaging the reduced power mode. It is recommended that the ARM bit be cleared whenever the idle state clock control is clear, and set whenever the idle state clock control is set Table 2±3. The set ARM bit causes an asynchronous response to all programmable interrupts when in the sleep state. (The cleared ARM bit yields the standard synchronous response at all times.) Affected interrupts include those tied to TIMER1 and TIMER2, as well as those tied to the inputs at Ports F, D2, D3, D4, and D5. The advantage to having the ARM bit set is that the device may be awakened by one of these interrupts, even when the PLL clock circuitry is stopped in sleep (by virtue of the idle state control). The disadvantage of the asynchronous response, however, is that it can render irregularities in the timing of response to these same inputs.

Note: Idle State Clock Control Bit

If the idle state clock control bit is set and the ARM bit is clear, the only event that can wake the C614 after an IDLE instruction is a hardware RESET low- to-high. When at sleep, the device will not respond to the input ports, nor to the internal timers.

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Texas Instruments MSP50C614 manual Reduced Power Modes

MSP50C614 specifications

The Texas Instruments MSP50C614 is a microcontroller that belongs to the MSP430 family, renowned for its low power consumption and versatile functionality. Primarily designed for embedded applications, this microcontroller is favored in various industries, including consumer electronics, industrial automation, and healthcare devices.

One of the standout features of the MSP50C614 is its ultra-low power technology, which enables it to operate in various power modes. This makes it ideal for battery-powered applications, where energy efficiency is crucial. The MSP430 architecture allows for a flexible power management system, ensuring that energy is conserved while providing robust performance.

The MSP50C614 is equipped with a 16-bit RISC CPU that delivers high performance while maintaining low power usage. With a maximum clock frequency of 16 MHz, it can execute most instructions in a single cycle, resulting in swift operation and responsive performance. This microcontroller also comes with a generous flash memory capacity, allowing developers to store large amounts of code and data conveniently.

In terms of peripherals, the MSP50C614 is highly versatile. It features a range of digital and analog input/output options, including multiple timers, GPIO ports, and various communication interfaces like UART, SPI, and I2C. This extensive set of peripherals allows for seamless integration with other components and simplifies the design of complex systems.

The integrated 12-bit Analog-to-Digital Converter (ADC) stands out as a valuable characteristic of the MSP50C614. This feature enables the microcontroller to convert physical analog signals into digital data, making it particularly useful for sensing applications and real-time monitoring.

Another noteworthy technology employed in the MSP50C614 is its support for low-voltage operations. With a broad supply voltage range, this microcontroller can function efficiently in diverse environments and is suitable for low-power applications, enhancing its practicality.

Moreover, Texas Instruments provides software support in the form of Code Composer Studio and various libraries that make it easier for developers to program and utilize the MSP50C614 effectively.

In summary, the Texas Instruments MSP50C614 microcontroller is a powerful, low-power solution equipped with the features and technologies necessary for efficient operation in a wide array of applications. Its blend of performance, flexibility, and energy efficiency makes it a popular choice among engineers and designers looking to create innovative, sustainable designs in the rapidly evolving tech landscape.