The LX1692 uses several pins to monitor for fault conditions like open lamps, broken lamps, or short circuits:
: When the system starts, an internal current source feeds the external capacitor on the C_TO pin. This action initiates a predictable voltage ramp.
Extends the charge duration, allowing older lamps more time to strike. Disabling the high-voltage block Permanently ground the primary protection sense lines.
Use 1% tolerance components in the divider network to prevent loose tolerances from causing premature shutdowns.
其保护逻辑较为精密。当灯管开路或接触不良时，变压器次级电压迅速上升，OV_SNS电压持续超过3.2V峰值后，芯片内部会启动一个4位累加计数器——每超限一次计数值递增，累计满16次后判定为开路故障，IC输出被永久锁存。此4位计数器会以100–300Hz的频率被C_BST信号周期性清零，因此只有持续时间足够长的连续过压才会触发锁定。
The LX1692 includes safety features to protect against fault conditions such as , broken lamp , and short-circuit faults . The protection mechanism operates as follows:
During normal operation, the IC expects the voltage at the PROT pin to remain within a tightly regulated, safe operating window. If an anomaly occurs in the CCFL circuit, the voltage on this pin shifts, triggering an internal latch that shuts down the controller to prevent catastrophic component failure or fire hazards. Internal Architecture and Fault Thresholds