STEVAL-A6986IV2

38V, 5W synchronous iso-buck converter evaluation board with single isolated output based on the A6986I. The primary output voltage can be accurately adjusted, whereas the isolated secondary output is generated by a transformer. No optocoupler is required. The primary sink capability (typ. 1.9 A) allows a proper energy transfer to the secondary side as well as enables a tracked soft-start of the secondary output. The control loop is based on a peak current mode architecture and the device operates in forced PWM. The 300ns blanking time filters oscillations generated by the transformer leakage inductance and makes the solution more robust. Pulse by pulse current sensing on both power elements implements an effective constant current protection on the primary side. Due to the primary reverse current limit, the secondary output is protected against short-circuit events. The secondary voltage is stabilized over current by using a power transistor and a shunt voltage reference (TL431).

• AEC-Q100 qualified
• Operating temperature range: -40 °C to 135 °C for Tj
• Designed for iso-buck topology
• 4V to 38V operating input voltage
• 8µA IQ-shutdown
• Adjustable fSW and synchronization
• Embedded primary output voltage supervisor
• Adjustable soft-start time
• Internal primary current limiting
• Overvoltage protection and thermal shutdown