SNVSCD1 September 2024 LM706A0-Q1
PRODUCTION DATA
The LM706A0-Q1 operational input voltage range is from 4.5V to 65V. The device is intended for step-down conversions from 12V, 24V and 48V automotive supply rails. The LM706A0-Q1 uses internal LDOs to provide an 8V or 5V VCC bias rail and a 5V VDDA rail for the gate drive and control circuits.
In high input voltage applications, make sure that the VIN and SW pins do not exceed the absolute maximum voltage rating of 70V during line or load transient events. Voltage excursions that exceed the absolute maximum ratings of these pins can damage the IC. Follow PCB board layout recommendations and use high-quality input bypass capacitors to minimize voltage overshoot and ringing.
As VIN approaches VOUT, the LM706A0-Q1 skips tOFF cycles to allow the controller to extend the duty cycle up to approximately 99%. Refer to Figure 6-1.
When in dropout, the output voltage tracks the input voltage and the peak current mode control is open loop. As a result, larger output voltage perturbations due to line and load transients are possible. Additional output capacitance and more aggressive external compensation can improve the output response.
Use Equation 1 to calculate when the LM706A0-Q1 enters dropout mode.