Lx1692 Protection Pin Jun 2026

In a standard backlight inverter circuit, the protection pins are configured using passive components to fine-tune the safety thresholds:

This pin monitors the output voltage of the transformer via a capacitive or resistive voltage divider. If the voltage exceeds a preset threshold, the IC limits the duty cycle or initiates a shutdown timer.

Protection on the LX1692 is typically managed through the following mechanisms:

: On the LX1692 , protection is typically managed via specific pins like Pin 4 (COMP) or Pin 14 (TIMER) , depending on the specific board revision and implementation. lx1692 protection pin

| 引脚号 | 引脚名称 | 功能说明 | 实测电压参考值（例） | | :--- | :--- | :--- | :--- | | | | | | | 20 | VDDP | 工作电压输入端，标称5V供电，最大耐压5.5V | 5.07V | | 6 | ENABLE | 点灯延时/使能控制脚，高电平有效 | 3.99V | | 1 | VDDA | 模拟电压调节器输出（4V LDO），可外接滤波电容 | 3.99V | | 17 | GND | 芯片地 | 0V | | 5 | IR | 内部偏置电流设定电阻输入端 | 理论值由R_IR决定 | | 故障检测与保护类 | | | | | 11 | OC_SNS | 过电流感测输入 ，接外部电阻采样变压器初级电流，超2V阈值即触发保护 | 0V（保护未被触发） | | 13 | OV_SNS | 过电压检测输入 ，监视灯管两端电压分压信号，配合1000:1分压网络 | 0.2V（灯管正常点燃） | | 14 | ISNS | 电流检测输入 ，采CCFL灯管回路电流，用于点火判定与稳流控制 | 0.14V（正常运行） | | 12 | ICOMP | 电流误差放大器输出端，外接RC补偿网络 | 3.99V | | 10 | VCOMP | 电压误差放大器补偿端 | 2.96V | | 亮度控制类 | | | | | 7 | BRITE_A | 模拟调光控制输入端（0–2.5V模拟电压） | 5.07V | | 9 | BRITE_D | 数字PWM调光控制输入端 | 0V | | 3 | C_BST | Burst调光模式频率设定电容引脚 | 0V | | 振荡与时序类 | | | | | 2 | C_R | 灯管工作频率设定电容引脚 | 0V | | 4 | C_TO | 外部定时电容，设定点火超时保护时长 | 0V | | 8 | VIN_SNS | 工作电压感测（配合输入电压前馈补偿） | 0V | | 驱动输出类 | | | | | 15 | DOUT | 缓冲器N-FET激励输出D（全桥逆变器下管驱动） | 0V | | 16 | COUT | 缓冲器N-FET激励输出C（全桥逆变器上管驱动） | 0V | | 18 | BOUT | 缓冲器N-FET激励输出B（副半桥下管驱动） | 56V（峰值） | | 19 | AOUT | 缓冲器N-FET激励输出A（副半桥上管驱动） | 0.058V（静默状态） |

Old CCFL bulbs require higher voltage to "strike," which can trip the over-voltage protection.

：LX1692IPW采用薄型TSSOP-20，适用于高度受限的超薄电视方案；LX1692IDW采用SOIC-20宽体封装，散热更好、人工焊接容错率更高，在维修市场更易操作。两者在不改变PCB布局的情况下 不能 直接互换。 In a standard backlight inverter circuit, the protection

Understanding the LX1692 Protection Pin: A Guide to Troubleshooting CCFL Inverter Circuits

To help you troubleshoot or design with this IC, let me know:

The LX1692 is a highly efficient Direct Drive CCFL (Cold Cathode Fluorescent Lamp) inverter controller designed for backlight applications in LCD monitors and televisions. A critical aspect of designing with or troubleshooting this integrated circuit (IC) is understanding its comprehensive protection mechanisms. These mechanisms are primarily monitored and controlled through a specific protection pin: . The Role of Pin 5 (PROT) in the LX1692 low-voltage DC signals.

If you are working on a specific display model right now, let me know of the TV or monitor. I can also help you look up the pinout diagram or detail what resistor values you will need for your specific board layout. Share public link

The PROT pin does not measure the high-voltage outputs directly. Instead, it interfaces with a network of sensing components that scale down the dangerous voltages and currents into manageable, low-voltage DC signals.