HOW DOES IT WORK?

Smart Buck 4 Click is based on the LTS3562, a quad synchronous step-down DC-DC regulator from Analog Devices. The LTS3562 has four independent I2C controllable step-down regulators, two of them with an output current of up to 600mA and two with an output current of up to 400mA. The Type A regulators are externally adjustable and have a programmable feedback voltage of 425mV up to 800mV (R600A, R400A) in 25mV steps. The Type B regulators have a fixed output, and their output voltages can be programmed between 600mV and 3.755V (R600B, R400B) in 25mV steps. The R600A regulator has a Power-on-reset output feature. Both Type A and Type B have separate RUN pins that can be enabled if I2C control is unavailable.

The LTS3562 has several programmable modes in which all four regulators can operate. In Pulse skip mode, an internal latch is set at the start of every 2.25MHz cycle, which turns the main P-channel MOSFET on. In LDO mode, the switching regulators are converted to linear regulators, thus delivering continuous power. This mode gives the LTS3562 a DC option and the lowest possible output noise. In Burst mode, the switching regulator automatically switches between the hysterical control and a fixed-frequency pulse skip operation. The first is automatically switched at light loads, while the latter is switched at heavy loads. In Forced Burst mode, the switching regulators use a constant-current algorithm to control the inductor current, and in this mode, the output power is limited.

The Smart Buck 4 Click uses a standard 2-Wire I2C interface to communicate with the host MCU supporting speeds up to 400KHz. The LTS3562 is a receive-only device, and the I2C address is fixed and can not be changed. As mentioned above, you can manage both Type A and Type B regulators with active LOW by a host MCU over the R40 and R60 pins.

This Click board™ can be operated only with a 3.3V logic voltage level. The board must perform appropriate logic voltage level conversion before using MCUs with different logic levels. However, the Click board™ comes equipped with a library containing functions and an example code that can be used, as a reference, for further development.

SPECIFICATIONS