ISL85403DEMO1Z

The ISL85403DEMO1Z is an evaluation board designed and manufactured by Intersil, Inc. It is a DC/DC & AC/DC (Off-Line) SMPS, which stands for Switch-Mode Power Supply. This evaluation board is designed to demonstrate the features and performance of the ISL85403 buck controller, a 265 kHz synchronous buck controller. It is ideal for applications such as server, storage, networking, boards and remote sites.

The evaluation board is designed with a wide input voltage range of 4.5 V to 36 V. It provides an output current up to 10 A and can support output voltages from 0.6 V to 5 V. The output power of 50 W complies with the ESA-PSAC level V. The high efficiency up to 97% is due to an improved primary side control algorithm and an optimized switch-node design. The load transient performance is improved by the new control architecture. It features soft-start, dynamic voltage scaling, and current limit protection.

This evaluation board is primarily designed for use as single output supplies. However, it can also be used in parallel to meet higher current requirements. The board is emulated to be connected to a resistor current-sensing pin to measure the highest accuracy of output current. The board has many programmable logic internal and external connections, including a precision clock signal, SPI/I2C interface, boot and enable pins, and an enable/disable pin. It also has an onboard protection circuitry with a signal topology fault detector, such as overload, output short-circuit, overvoltage, and undervoltage protection.

Working principle of the ISL85403DEMO1Z evaluation board is described as follows. The built-in PWM (Pulse Width Modulation) controller creates a pulse width modulated signal using the powertrain divider, the control loop function, and the clock. The closed loop design constantly monitors the output voltage by comparing it with a reference voltage. When the output voltage is higher than the reference voltage, the controller reduces the duty cycle and thus reduces the energy being supplied to the load. On the other hand, when the output voltage is lower than the reference voltage, the duty cycle is increased and the energy being supplied to the load is also increased. This ensures that the output voltage remains constant regardless of the load. The loop compensator stabilizes the system by reducing oscillations and ringing, and providing fast response times to any output voltage change due to high or low load current conditions.

The ISL85403DEMO1Z evaluation board is a powerful and reliable DC/DC & AC/DC (Off-Line) SMPS solution. With this evaluation board, users can easily design and prototype the designs of their products. This evaluation board provides the best solution for applications such as server, storage, networking, boards and remote sites.