ZHCSK37 August 2019 LP8867C-Q1 , LP8869C-Q1
PRODUCTION DATA.
A summary of the LP886xC-Q1 fault detection behavior is shown in Table 3. Detected faults (excluding LED open or short) cause device to enter FAULT RECOVERY state. In FAULT_RECOVERY the DC-DC and LED current sinks of the device are disabled, and the FAULT pin is pulled low. The device will exit FAULT RECOVERY mode after 100 ms and try the start-up sequence again. When recovery is successful and device enters into NORMAL state, the FAULT pin is released high.
FAULT/
PROTECTION |
FAULT NAME | CONDITION | FAULT PIN | Enter FAULT_
RECOVERY STATE |
ACTIVE STATE | ACTION |
---|---|---|---|---|---|---|
VIN overvoltage protection | VIN_OVP | VIN > 42 V
|
Yes | Yes | SOFT START, BOOST START, NORMAL | Device enters into FAULT RECOVERY state, and restarts after 100 ms |
VIN undervoltage protection | VIN_UVLO | Effective when VIN < 3.85 V
Released when VIN >4 V |
Yes | Yes | SOFT START, BOOST START, NORMAL | Device enters into FAULT RECOVERY state, and restarts after 100 ms |
Open LED fault | LED _OPEN | Adaptive Voltage is max. and
any OUTx voltage < 0.9 V |
Yes | No | NORMAL | Open string is removed from the DC-DC voltage control loop and output is disabled.
Fault pin low could be released by toggling VDDIO/EN pin, If VDDIO/EN is low for a period of 2 µs to 20 µs, LEDs are turned off for this period but device stays in NORMAL. |
Shorted LED fault | LED_SHORT | One of OUTx voltage is [0.9 V, 1.9 V] and
any OUTx voltage > 6 V |
Yes | No | NORMAL | Short string is removed from the DC-DC voltage control loop and output is disabled.
Fault pin low could be released by toggling VDDIO/EN pin, If VDDIO/EN is low for a period of 2 µs to 20 µs, LEDs are turned off for this period but device stays NORMAL. |
Boost overvoltage protection | BST_OVP | VFB > 2.3 V | Yes | Yes | NORMAL | Fault is detected if boost overvoltage condition duration is more than 560 ms
Device enters into FAULT RECOVERY state, and restarts after 100 ms |
SW overvoltage protection | SW_OVP | VSW > 49 V | Yes | Yes | SOFT START, BOOST START, NORMAL | Device enters into FAULT RECOVERY state, and restarts after 100 ms |
Thermal protection | TSD | Effective when Tj > 165 ºC
Released when Tj < 145 ºC |
Yes | Yes | SOFT START, BOOST START, NORMAL | Device enters into FAULT RECOVERY state, and restarts until TSD fault is released |