NCV78514

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16

Table 14. ILED DERATING SUMMARY TABLE

ILED Derating List

Reset

DIM Current Sink

Output State

IC over temperature (Warning)

−

> P_DIM_IQ

ILED Derated

Low BAT voltage

−

> P_DIM_IQ

ILED Derated following (BAT +1)/10 rule

PTC or NTC Over temperature (ILED < ISTOP)

> P_DIM_IQ

ILED Derate

Inductor I PEAK

−

> P_DIM_IQ

ON but limited power

Table 15. PROTECTIONS AND ERROR MANAGEMENT SUMMARY TABLE

Protections and Errors List

Reset

DIM Current Sink

Output State

Overvoltage

Comp. Hysteresis

< P_DIM_IFAULT

LED OFF

BAT < UVLO

Comp Hysteresis

< P_DIM_IFAULT

LED OFF

IC over temperature (TJ_OFF)

Comp. Hysteresis

< P_DIM_IFAULT

LED OFF

IC over temperature (TJ_OFF) − 40 % ILED derate

BAT POR

< P_DIM_IFAULT

LED OFF

ILED = ISTOP more than TFAULT

BAT POR

< P_DIM_IFAULT

LED OFF

LED + shorted to GND or LED −

BAT POR

< P_DIM_IFAULT

LED OFF

LED + string opened

BAT POR

< P_DIM_IFAULT

LED OFF

SNS P or N opened

BAT POR

< P_DIM_IFAULT

LED OFF

SNS P and N shorted

BAT POR

< P_DIM_IFAULT

LED OFF

RSET out of range

Auto restart

< P_DIM_IFAULT

LED OFF

Table 16. TIMING TABLE SUMMARY

Parameter

Timings

VREG_OK

No debounce, 2 ms response time

VREF_OK

No debounce, 2 ms response time

VDRV_OK

No debounce, 2 ms response time

UVLO

No debounce, 2 ms response time, Functional State Machine. Synchro rise & fall

OVLO

No debounce, 2 ms response time, Functional State Machine. Falling + 20 ms FAULT state timer

TSD

No debounce, 2 ms response time, Functional State Machine. Falling + 20 ms FAULT state timer

VLED H

Debounce 8 ms rising

VLED L

Debounce 5 ms after bob_running. Debounce 8 ms in running mode.

SNSP&N opened

Debounce 150 ms in running mode.

SNSP&N shorted

Blanking 8 ms after bob_running. Debounce 150 ms in running mode.

RSET OOR

90 ms

BAT

10 ms before derating

BAT derating

256 ms (de)rating slope

PTC/NTC derating

256 ms (de)rating slope

DIM slope

P_DIM_SLOPE (Option)

IC temp

Direct derating