VIN UVLO

SS

SSSR

1.25V

1.25V

0.45V

1.0V

SS

Primary

SR1, SR2

SSSR

1.0V

VOUT

1.0V

Prebiased Load

COMP

Secondary

Bias

2.0V

LM5045

SNVS699G – FEBRUARY 2011 – REVISED MARCH 2013

www.ti.com

Figure 17. Pre-Bias Voltage Startup Waveforms

Soft-Stop Off

The Soft-Start Off (SSOFF) pin gives additional flexibility by allowing the power converter to be configured for

hard-stop during line UVLO and hiccup mode condition. If the SS OFF pin is pulled up to the 5V REF pin, the

power converter hard-stops in any fault condition. Hard-stop drives each control output to a low state

immediately. Refer to Table 1 for more details.

Figure 18. Stop-Stop Waveforms during a UVLO Event

20

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