TL431的幾種基本用法

1、TL431的幾種基本用法介紹:TL431是一個(gè)有良好的熱穩(wěn)定性能的三端可調(diào)分流基準(zhǔn)電壓源。它的輸出電壓用兩個(gè)電阻就可以任意地設(shè)置到從Vref（2.5V）到36V范圍內(nèi)的任何值。該器件的典型動(dòng)態(tài)阻抗為0.2，在很多應(yīng)用中可以用它代替齊納二極管，例如，數(shù)字電壓表，運(yùn)放電路、可調(diào)壓電源，開關(guān)電源等等。特點(diǎn)：可編程輸出電壓為36V電壓參考誤差：0.4 ，典型值25（TL431B） 低動(dòng)態(tài)輸出阻抗，典型0.22負(fù)載電流能力1.0mA to 100mA等效全范圍溫度系數(shù)50 ppm/典型 溫度補(bǔ)償操作全額定工作溫度范圍低輸出噪聲電壓 圖1 TO92封裝引腳圖圖2 8腳封裝引腳功能圖3 SOP-8 貼片封裝

2、引腳圖圖4 TL431符號(hào)及內(nèi)部方框圖 圖5 TL431內(nèi)部電路圖MAXIMUM RATINGS (Full operating ambient temperature range applies, unlessotherwise noted.)最大額定值（環(huán)境溫度范圍適用，除非另有說明。 ）Rating 參數(shù)Symbol 符號(hào) 數(shù)值Unit 單位 Cathode to Anode Voltage陰極陽極電壓VKA 37 V Cathode Current Range, Continuous 陰極電流范圍，連續(xù)IK 100 to +150 mA Reference Input Current

3、Range, Continuous 參考輸入電流范圍，連續(xù)Iref 0.05 to +10 mA OperatingJunctionTemperature工作結(jié)溫TJ 150 Operating Ambient Temperature Range 操作環(huán)境溫度范圍TL431I,TL431AI, TL431BI TA 40 to +85 TL431C, TL431AC, TL431BC0 to +70StorageTemperature Range儲(chǔ)存溫度范圍Tstg 65 to +150 Total Power Dissipation總耗散功率 常溫 TA = 25 Derate above

4、25 Ambient TemperatureD, LP后綴塑封PD 0.70W P后綴塑封1.10 DM 后綴塑封0.52Total Power Dissipation TC = 25 Derate above 25 Case Temperature 總耗散功率 外殼溫度D, LP后綴塑封PD 1.5 W P后綴塑封3.0RECOMMENDED OPERATING CONDITIONS建議操作條件 Condition 條件Symbol 符號(hào) Min最大值 Max最小值 Unit 單位 Cathode to Anode Voltage 陰極陽極電壓VKA Vref 36 V Cathode Cu

5、rrent 陰極電流IK 1.0 100 mA THERMAL CHARACTERISTICS熱特性 Characteristic 特性 Symbol 符號(hào) D, LP后綴封裝P后綴封裝DM 后綴封裝Unit 單位 Thermal Resistance, JunctiontoAmbient 熱阻，結(jié)點(diǎn)到環(huán)境RqJA 178 114 240 /W Thermal Resistance, JunctiontoCase 熱阻，結(jié)到外殼RqJC 83 41 /WELECTRICAL CHARACTERISTICS(TA=25, unless otherwise noted.)電氣特性（25 ，除非另有

6、說明。） Characteristic 特性 Symbol 符號(hào) TL431I TL431C Unit 單位最小值 典型值 最大值最小值 典型值 最大值Reference Input Voltage (Figure 1)參考輸入電壓 VKA = Vref, IK = 10 mA TA = 25Vref 2.44 2.495 2.55 2.44 2.495 2.55 V TA = Tlow to Thigh (Note 1)2.412.582.423 2.567Reference Input Voltage Deviation Over Temperature Range參考輸入電壓偏差溫度范圍

7、 (Figure 1, Notes 1, 2) VKA= Vref, IK = 10 mA DVref 7.0 30 3.0 17 mV Ratio of Change in Reference Input Voltage to Change in Cathode to Anode Voltage IK = 10 mA (Figure 2), VKA = 10 V to Vref VrefVKA 1.4 2.7 1.4 2.7 mV/V VKA=36V to 10 V-1.0 2.01.02.0 Reference Input Current (Figure 2) 參考輸入電流IK = 10

8、mA, R1 = 10k, R2 = TA = 25Iref 1.8 4.0 1.8 4.0 A TA = Tlow to Thigh (Note 1)6.55.2 Reference Input Current Deviation Over Temperature Range參考輸入電流偏差溫度范圍 (Figure 2, Note 1, 4) IK = 10 mA, R1 = 10 k, R2 = DIref 0.8 2.5 0.4 1.2 A Minimum Cathode Current For Regulation VKA = Vref (Figure 1) 最小陰極電流調(diào)節(jié)Imin

9、0.5 1.0 0.5 1.0 mA OffState Cathode Current (Figure 3) VKA = 36 V, Vref = 0 V 斷態(tài)陰極電流Ioff 260 1000 260 1000 nA Dynamic Impedance (Figure 1, Note 3)動(dòng)態(tài)阻抗 VKA = Vref, DIK=1.0mA to 100mA f 3 1.0kHz |ZKA| 0.22 0.5 0.22 0.5 ELECTRICAL CHARACTERISTICS (TA = 25, unless otherwise noted.)電氣特性（25，除非另有說明。） Chara

10、cteristic 特性 Symbol 符號(hào) TL431AI TL431AC TL431BI Unit 單位最小值 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)參考輸入電壓 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 to Thigh 2.44 2.552.4532.5372.4752.4952.515 Reference Input Voltage Deviat

11、ion Over Temperature Range (Figure 1, Notes 1, 2) 參考輸入電壓偏差溫度范圍VKA= Vref, IK = 10 mA DVref 7.0 30 3.0 17 3.0 17 mV Ratio of Change in Reference Input Voltage to Change in Cathode to Anode Voltage IK = 10 mA (Figure 2), VKA = 10 V to VrefVrefVKA 1.4 2.7 1.4 2.7 1.4 2.7 mV/V VKA = 36 V to 10 V 1.02.01.

12、02.01.02.0 Reference Input Current (Figure 2)參考輸入電流 IK = 10 mA, R1 = 10 k, R2 = TA = 25 Iref 1.8 4.0 1.8 4.0 1.1 2.0 A TA = Tlow to Thigh (Note 1)6.5 5.24.0 Reference Input Current Deviation Over Temperature Range (Figure 2, Note 1) IK = 10 mA, R1 = 10k, R2 = 參考輸入電流偏差溫度范圍DIref 0.8 2.5 0.4 1.2 0.8 2.

13、5 A Minimum Cathode Current For Regulation 最小陰極電流調(diào)節(jié)VKA = Vref (Figure 1) Imin 0.5 1.0 0.5 1.0 0.5 1.0 mA OffState Cathode Current(Figure 3) 斷態(tài)陰極電流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 動(dòng)態(tài)阻抗|ZKA| 0.22 0.5 0.22 0.5 0.14 0.3 圖6 測(cè)試電路VKA = Vref 圖7 測(cè)試電路VKA Vref圖8 測(cè)試電路for Ioff曲線圖：圖9 陰極電流與陰極電壓 圖10陰極電流與陰極電壓圖11 參考輸入電壓與常溫 圖12 參考輸入電流與常溫圖13 變化的參考輸入電壓與陰極電壓圖14 斷態(tài)陰極電流隨環(huán)境溫度圖15 動(dòng)態(tài)阻抗與頻率圖16 動(dòng)態(tài)阻抗隨環(huán)境溫度圖17開環(huán)電壓增益與頻率圖18譜噪聲密度 圖19 脈沖響應(yīng)圖20 穩(wěn)定的邊界條件應(yīng)用法：圖21測(cè)試電路曲線a 邊界條件的穩(wěn)定性 圖22曲線測(cè)試電路的B，C和D邊界條件的穩(wěn)定性圖23并