ADP2311

Data Sheet

Rev. B | Page 16 of 20

THERMAL SHUTDOWN

If the ADP2311 junction temperature exceeds 150°C, the PFO

pin is immediately pulled low, and Channel 2 enters power feed-

the POR and RSTO pins are pulled low. When the FB2 voltage falls

below 48 mV, Channel 1 turns off and enters discharge mode.

A 15°C hysteresis is included so that the ADP2311 does not

recover from thermal shutdown until the on-chip temperature

falls below 135°C. Upon recovery, a soft start is initiated before

normal operation. Figure 37 shows the power sequence during

thermal protection based on the circuit shown in Figure 38.

FB2

(INT)

WDI

(FROM

PROCESSOR)

PFO

WHEN THE JUNCTION TEMPERATURE IS

HIGHER THAN 150°C, PFO IS IMMEDIATELY

PULLED LOW, AND CHANNE L 2 ENTERS

POWER FEEDBACK MODE.

WHEN FB2 FALLS TO 95% OF ITS NOMINAL

VALUE, POR AND RSTO ARE PULLED LOW.

WHEN FB2 DISCHARGES TO 48mV,

CHANNEL 1 TURNS OFF.

FB1

POR

THERMAL

SHUTDOWN

WHEN THE JUNCTION

TEMPERATURE IS LOWER

THAN 135°C, THE PART

POWERS UP AGAIN USING THE

NORMAL START-UP ROUTINE.

PWM1

PWM2

48mV

95%

POWER

FEEDBACK MODE

48mV

RSTO

Figure 37. Power Sequence During Thermal Protection Based on the Circuit Shown in Figure 38