爱华网TL431是一个有良好的热稳定性能的三端可调分流基准电压源。它的输出电压用两个电阻就可以任意地设置到从Vref（2.5V）到36V范围内的任何值。该器件的典型动态阻抗为0.2Ω，在很多应用中可以用它代替齐纳二极管，例如，数字电压表，运放电路、可调压电源，开关电源等等。
特点：
•可编程输出电压为36V
•电压参考误差：±0.4％ ，典型值@25℃（TL431B）
•低动态输出阻抗，典型0.22Ω
•负载电流能力1.0mA to 100mA
•等效全范围温度系数50 ppm/℃典型
• 温度补偿操作全额定工作温度范围
•低输出噪声电压
图1 TO92封装引脚图
图3 SOP-8 贴片封装引脚图
图4 TL431符号及内部方框图
图5 TL431内部电路图
MAXIMUM RATINGS (Full operatingambient temperature range applies, unless
otherwise noted.)最大额定值（环境温度范围适用，除非另有说明。 ）
Rating 参数 | Symbol符号 | 数值 | Unit单位 | |
Cathode to Anode Voltage阴极阳极电压 | VKA | 37 | V | |
Cathode Current Range, Continuous阴极电流范围，连续 | IK | –100 to +150 | mA | |
Reference Input Current Range, Continuous参考输入电流范围，连续 | Iref | –0.05 to +10 | mA | |
OperatingJunctionTemperature工作结温 | TJ | 150 | ℃ | |
Operating Ambient Temperature Range操作环境温度范围 | TL431I,TL431AI, TL431BI | TA | –40 to +85 | ℃ |
| TL431C, TL431AC, TL431BC | 0to +70 | |||
StorageTemperature Range储存温度范围 | Tstg | –65 to +150 | ℃ | |
Total Power Dissipation总耗散功率 常温@ TA = 25℃ Derateabove 25℃ Ambient Temperature | D, LP后缀塑封 | PD | 0.70 | W |
| P后缀塑封 | 1.10 | |||
| DM 后缀塑封 | 0.52 | |||
Total Power Dissipation @ TC = 25℃ Derate above25℃ Case Temperature 总耗散功率 外壳温度 | D, LP后缀塑封 | PD | 1.5 | W |
| P后缀塑封 | 3.0 | |||
RECOMMENDED OPERATINGCONDITIONS建议操作条件
Condition 条件 | Symbol符号 | Min最大值 | Max最小值 | Unit单位 |
Cathode to Anode Voltage 阴极阳极电压 | VKA | Vref | 36 | V |
Cathode Current 阴极电流 | IK | 1.0 | 100 | mA |
THERMALCHARACTERISTICS热特性
| Characteristic特性 | Symbol符号 | D,LP后缀封装 | P后缀封装 | DM 后缀封装 | Unit单位 |
| Thermal Resistance,Junction–to–Ambient 热阻，结点到环境 | RqJA | 178 | 114 | 240 | ℃/W |
| Thermal Resistance, Junction–to–Case热阻，结到外壳 | RqJC | 83 | 41 | – | ℃/W |
ELECTRICAL CHARACTERISTICS(TA=25℃,unless otherwise noted.)电气特性（25℃ ，除非另有说明。）
| Characteristic 特性 | Symbol符号 | TL431I | TL431C | Unit 单位 | |||||
| 最小值 | 典型值 | 最大值 | 最小值 | 典型值 | 最大值 | ||||
| Reference Input Voltage(Figure 1)参考输入电压 VKA = Vref, IK = 10mA | TA = 25℃ | Vref | 2.44 | 2.495 | 2.55 | 2.44 | 2.495 | 2.55 | V |
| TA = Tlow to Thigh (Note1) | 2.41 | – | 2.58 | 2.423 | – | 2.567 | |||
| Reference Input VoltageDeviation Over Temperature Range参考输入电压偏差温度范围 (Figure 1, Notes 1, 2)VKA= Vref, IK = 10 mA | DVref | – | 7.0 | 30 | – | 3.0 | 17 | mV | |
| Ratio of Change inReference Input Voltage to Change in Cathode to Anode Voltage IK =10 mA (Figure 2), | △VKA = 10 V toVref | △Vref △VKA | – | –1.4 | –2.7 | – | –1.4 | –2.7 | mV/V |
| △VKA=36V to 10 V | - | –1.0 | –2.0 | – | –1.0 | –2.0 | |||
| Reference Input Current(Figure 2) 参考输入电流IK = 10 mA, R1 = 10k, R2 =∞ | TA = 25℃ | Iref | – | 1.8 | 4.0 | – | 1.8 | 4.0 | μA |
| TA = Tlow to Thigh (Note1) | – | – | 6.5 | – | – | 5.2 | |||
| Reference Input CurrentDeviation Over Temperature Range参考输入电流偏差温度范围 (Figure 2, Note 1, 4)IK = 10 mA, R1 = 10 k, R2 = ∞ | DIref | – | 0.8 | 2.5 | – | 0.4 | 1.2 | μA | |
| Minimum Cathode CurrentFor Regulation VKA = Vref (Figure 1) 最小阴极电流调节 | Imin | – | 0.5 | 1.0 | – | 0.5 | 1.0 | mA | |
| Off–State CathodeCurrent (Figure 3) VKA = 36 V, Vref = 0 V 断态阴极电流 | Ioff | – | 260 | 1000 | – | 260 | 1000 | nA | |
| Dynamic Impedance(Figure 1, Note 3)动态阻抗 VKA = Vref, DIK=1.0mA to 100mA f 31.0kHz | |ZKA| | – | 0.22 | 0.5 | – | 0.22 | 0.5 | Ω | |
ELECTRICAL CHARACTERISTICS (TA =25℃, unless otherwise noted.)电气特性（25℃，除非另有说明。）
Characteristic特性 | Symbol 符号 | TL431AI | TL431AC | TL431BI | Unit单位 | |||||||||
| 最小值 | 典型值 | 最大值 | 最小值 | 典型值 | 最大值 | 最小值 | 典型值 | 最大值 | ||||||
| Reference Input Voltage(Figure 1)参考输入电压 VKA = Vref, IK = 10 mA | TA = 25℃ | Vref | 2.47 | 2.495 | 2.52 | 2.47 | 2.495 | 2.52 | 2.483 | 2.495 | 2.507 | V | ||
| TA = Tlow toThigh | 2.44 | – | 2.55 | 2.453 | – | 2.537 | 2.475 | 2.495 | 2.515 | |||||
| Reference Input VoltageDeviation Over Temperature Range (Figure 1, Notes 1, 2)参考输入电压偏差温度范围VKA= Vref, IK = 10 mA | DVref | – | 7.0 | 30 | – | 3.0 | 17 | – | 3.0 | 17 | mV | |||
| Ratio ofChange in Reference Input Voltage to Change in Cathode to AnodeVoltage IK = 10 mA (Figure 2), | △VKA = 10 V toVref | △Vref △VKA | – | –1.4 | –2.7 | – | –1.4 | –2.7 | – | –1.4 | –2.7 | mV/V | ||
| △VKA = 36 V to 10V | – | –1.0 | –2.0 | – | –1.0 | –2.0 | – | –1.0 | –2.0 | |||||
| ReferenceInput Current (Figure 2)参考输入电流 IK = 10 mA, R1 = 10 k, R2 =∞ | TA = 25℃ | Iref | – – | 1.8 | 4.0 | – | 1.8 | 4.0 | – | 1.1 | 2.0 | μA | ||
| TA = Tlow to Thigh (Note1) | – | 6.5 | – | – | 5.2 | – | – | 4.0 | ||||||
| Reference Input CurrentDeviation Over Temperature Range (Figure 2, Note 1) IK = 10 mA, R1= 10k, R2 = ∞ 参考输入电流偏差温度范围 | DIref | – | 0.8 | 2.5 | – | 0.4 | 1.2 | – | 0.8 | 2.5 | μA | |||
| Minimum Cathode CurrentFor Regulation 最小阴极电流调节VKA = Vref (Figure 1) | Imin | – | 0.5 | 1.0 | – | 0.5 | 1.0 | – | 0.5 | 1.0 | mA | |||
| Off–State CathodeCurrent(Figure 3) 断态阴极电流VKA = 36V, Vref =0V | Ioff | – | 260 | 1000 | – | 260 | 1000 | – | 230 | 500 | nA | |||
| Dynamic Impedance(Figure 1, Note 3) VKA = Vref, DIK = 1.0 mA to 100 mA f 3 1.0 kHz动态阻抗 | |ZKA| | – | 0.22 | 0.5 | – | 0.22 | 0.5 | – | 0.14 | 0.3 | Ω | |||
图6 测试电路VKA =Vref图7 测试电路VKA >Vref图8测试电路for Ioff
应用法：
图2--3并联稳压器电路图图24大电流并联稳压器电路
图25控制三端固定稳压输出电路图26串联稳压调节电路图27 过压保护电路
图28恒流源电路图29恒定流入电流源电路图30双向可控硅过压保护电路
图31电压监视器电路图32单电源比较温度补偿电路
图33线性欧姆表电路图图34简单的400毫瓦唱机放大器电路
图35 高效率降压型开关转换器电路图
图36 简体TL431器件模型
封装图
SOP-8 贴片封装图
