SM2188EH 线性恒流产品系列
产品介绍
SM2188EH 是一款无频闪、可满足新 ERP 标准的 LED 线性恒流控制芯片，内置过温保护功能，提升系统应用可靠性。外围可通过调节 REXT 电阻值对输出电流进行调节。同时 SM2188EH 集成了输入线电压补偿功能，在输入线高电压过时，按照外置的补偿电阻减小电解充电电流，以满足新 ERP 标准。
其主要应用于 LED 照明、建筑亮化工程等领域，系统结构简单， 外围元件少，PCB 走线简洁，方案成本低。
产品特点
本司专利的恒流控制技术
支持输入电压：120Vac/220Vac
无频闪、可满足新 ERP 标准要求
芯片间输出电流偏差<±5%
无需磁性元器件可满足 EMI 应用
具有过温调节功能
封装形式：ESOP8
产品应用
LED 日光灯管 T5/T8
LED 球泡灯
投光灯
工矿灯
灯具类 LED 照明
应用电路图原理
典型方案
1. Adjust the output current value by changing the resistance value of R1;
2. Adjust the electrolysis charging current by changing the resistance value of R2; R3 is the detection resistance of the system VT pin, and the recommended value is 1M;
3. The voltage drop of the light string is recommended to be 250~260V;
4. To improve system reliability, RV1 is recommended to be retained.
PCB layout Attention
（1） IC substrate and PCB use solder paste process, to guarantee better touch of IC substrate and PCB. Red glue process is prohibited on IC substrate.
（2） Actual system output power is related to heat dissipation of PCB board and lamp shell, actual application power needs to match heat dissipation condition.
（3） Laying copper on IC substrate for heat dissipation and improve reliability. Copper laying is shown above, suggested substrate bonding pad size is 2.5mm*1.8mm.
（4） Leakage of copper from IC substrate pad must keep at least 0.8mm away from the OUT port
引脚定义及功能详解
管脚说明
| 编号 | 名称 | 说明 |
| 1、2 | NC | No connection |
| 3 | REXT1 | Output current setting port1 |
| 4 | REXT2 | Output current setting port2 |
| 5 | OUT2 | Power input and constant current output port 2 |
| 6 | VT | Constant power setting port2 |
| 7 | NC | Connect to ground when applied |
| 8 | OUT1 | Power input and constant current output port 1 |
| Substrate | GND | Ground |
