3ms

3ms

1ms

GPI

GPO

UCD90160

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SLVSAC8A

– NOVEMBER 2010 – REVISED APRIL 2011

Table 5. Rail-Status Types for Boolean Logic

Rail-Status Types

POWER_GOOD

TON_MAX_FAULT

VOUT_UV_WARN_LATCH

MARGIN_EN

TOFF_MAX_WARN

VOUT_UV_FAULT_LATCH

MRG_LOW_nHIGH

SEQ_ON_TIMEOUT

TON_MAX_FAULT_LATCH

VOUT_OV_FAULT

SEQ_OFF_TIMEOUT

TOFF_MAX_WARN_LATCH

VOUT_OV_WARN

SYSTEM_WATCHDOG_TIMEOUT

SEQ_ON_TIMEOUT_LATCH

VOUT_UV_WARN

VOUT_OV_FAULT_LATCH

SEQ_OFF_TIMEOUT_LATCH

VOUT_UV_FAULT

VOUT_OV_WARN_LATCH

SYSTEM_WATCHDOG_TIMEOUT_LATCH

GPO Delays

The GPOs can be configured so that they manifest a change in logic with a delay on assertion, deassertion, both

or none. GPO behavior using delays will have different effects depending if the logic change occurs at a faster

rate than the delay. On a normal delay configuration, if the logic for a GPO changes to a state and reverts back

to previous state within the time of a delay then the GPO will not manifest the change of state on the pin. In

Figure 15 the GPO is set so that it follows the GPI with a 3ms delay at assertion and also at de-assertion. When

the GPI first changes to high logic state, the state is maintained for a time longer than the delay allowing the

GPO to follow with appropriate logic state. The same goes for when the GPI returns to its previous low logic

state. The second time that the GPI changes to a high logic state it returns to low logic state before the delay

time expires. In this case the GPO does not change state. A delay configured in this manner serves as a glitch

filter for the GPO.

Figure 15. GPO Behavior When Not Ignoring Inputs During Delay

The Ignore Input During Delay bit allows to output a change in GPO even if it occurs for a time shorter than the

delay. This configuration setting has the GPO ignore any activity from the triggering event until the delay expires.

Figure 16 represents the two cases for when ignoring the inputs during a delay. In the case in which the logic

changes occur with more time than the delay, the GPO signal looks the same as if the input was not ignored.

Then on a GPI pulse shorter than the delay the GPO still changes state. Any pulse that occurs on the GPO when

having the Ignore Input During Delay bit set will have a width of at least the time delay.

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© 2010–2011, Texas Instruments Incorporated

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