HIP6013 datasheet(10/11 Pages) INTERSIL

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Schottky Selection

Rectiﬁer D2 conducts when the upper MOSFET Q1 is off.

The diode should be a Schottky type for low power losses.

The power dissipation in the Schottky rectiﬁer is

approximated by:

In addition to power dissipation, package selection and

heatsink requirements are the main design tradeoffs in

choosing the Schottky rectifier. Since the three factors are

interrelated, the selection process is an iterative procedure.

The maximum junction temperature of the rectifier must

remain below the manufacturer’s specified value, typically

125oC. By using the package thermal resistance specification

and the Schottky power dissipation equation (shown above),

the junction temperature of the rectifier can be estimated. Be

sure to use the available airflow and ambient temperature to

determine the junction temperature rise.

FIGURE 10. UPPER GATE DRIVE - DIRECT VCC DRIVE OPTION

+12V

HIP6013

GND

UGATE

PHASE

BOOT

VCC

+5V OR LESS

NOTE:

VG-S ≈ VCC - 5V

PCOND = IO x Vf x (1 - D)

Where: D is the duty cycle = VO/VIN, and

Vf is the schottky forward voltage drop

HIP6013

HIP6013 Datasheet(PDF) 10 Page - Intersil Corporation