TS4431AILT

TS4431 1.224V Open Collector Shunt Voltage Reference ■ Internal 1.224V ±0.5% precision ■ Low output saturation voltage 75 mV max between SINK and GND ■ Low current consumption: 250µA ■ Industrial temperature range: -40 to +85°C ■ 100ppm/°C temperature coefficient SOT23-5L (Plastic Micropackage) Pin connections (top view) Description The TS4431 is a four-terminal device dedicated to low voltage Switch Mode Power Supplies (SMPS). It integrates a 1.224V voltage reference, an amplifier, and an open collector output transistor in a single package. The TS4431’s operating mode is similar to the well-known standard voltage reference, the TL431. It maintains the desired feedback voltage at the REF pin in a closed loop configuration by sinking a current proportional to the error voltage at the REF pin. TS4431 features an open collector transistor with an ultra-low saturation voltage, allowing it to be used in series with the optocoupler in an SMPS architecture to regulate low voltage SMPS. 1 Vc c Sink 5 Ref 4 2 Gnd 3 Nc Applications ■ Low voltage switch mode power supplies ■ Isolated DC/DC converter ■ Computers ■ Low voltage discrete regulator Order Codes Part Number TS4431AILT TS4431ILT November 2005 Accuracy Temperature Range Package Packing -40, +85°C SOT23-5 Tape & Reel 0.5% 1% Marking L288 L275 Rev 2 1/8 www.st.com 8 Absolute Maximum Ratings 1 TS4431 Absolute Maximum Ratings Table 1. Key parameters and their absolute maximum ratings Symbol Parameter Value Unit ISINK Output sink current 30 mA VCC Supply voltage 12 V VSINK Output voltage 12 V Power Dissipation (1)SOT23-5 500 mW -65 to +150 °C 2 kV Machine Model (MM) 200 V Lead Temperature (soldering, 10 seconds) 250 °C Value Unit Operating temperature range -40 to +85 °C VCC Supply voltage 1.5 to 10 V ISINK Output sink current 20 mA PD TSTD Storage Temperature Human Body Model (HBM) ESD TLEAD 1. PD has been calculated with TAMB = 25°C, TJunction=150°C and RthJA = 250°C/W for the SOT23-5 package RthJC = 81°C/W for the SOT23-5 package Table 2. Operating conditions Symbol TOPER 2/8 Parameter Typical Application Schematic 2 TS4431 Typical Application Schematic Figure 1. SMPS power supply: secondary side Vout L1 D1 D2 C1 R1 1 Vcc U1 TS4431 Sink 5 R2 Cd1 100nF 2 Gnd Vref R3 3 3/8 Nc Ref 4 Electrical Characteristics 3 TS4431 Electrical Characteristics Table 3. Electrical characteristics for Tamb = 25°C, VCC = 1.8V, ISINK = 2mA unless otherwise specified Symbol Parameter VREF Reference voltage TS4431A 0.5% VREF Reference voltage TS4431 1% TC Min. Typ. Max. 1.218 1.224 1.230 1.209 1.212 1.239 1.224 1.203 1.245 Temperature coefficient ∆ V REF ----------------∆ ISIN K Change in VREF due to change in ISINK Supply current 100 VCC =1.5 to 10V 1 2 -40°C < T < +85°C 2 3 ISINK=0.5 to 20mA 7 10 mV -40°C < T < +85°C ISINK=2mA Ref < 0.6V OFF-State supply current IREF Reference input current 15 250 15 0.1< ISINK < 10mA ISINK=5mA IOH Note: 4/8 Output leakage current µA 20 µA -40°C < T < +85°C Output transistor saturation voltage 300 350 30 0.4 1 µA -40°C < T < +85°C VSAT ppm/°C mV -40°C < T < +85°C IOFF 1.236 V -40°C < T < +85°C Change in VREF due to change in VCC Unit V -40°C < T < +85°C ∆ VREF ----------------∆ VCC ICC Test Condition 2 30 -40°C < T < +85°C 50 60 mV ISINK=20mA 90 100 -40°C < T < +85°C 120 VSINK=VCC 0.05 -40°C < T < +85°C 0.1 µA Limits are 100% production tested at 25°C. Limits over temperature are guaranteed through correlation and by design. Electrical Characteristics Vref vs. temp. Isink=2mA Figure 3. 1.225 1.228 1.224 1.226 1.223 1.224 Vref (V) Vref (V) Figure 2. TS4431 1.222 1.221 1.22 1.222 1.22 1.218 1.219 1.216 1.218 -40°C -20°C 0°C 25°C 50°C -40°C -20°C 85°C Figure 5. Vcc=1.5V Icc vs. temp. Isink=2mA 300 250 200 150 100 50 0 -20°C 0°C 25°C 50°C 85°C -40°C -20°C Tem perature (°C) 0°C 25°C 50°C 85°C Tem perature (°C) Vcc=1.5V to 10V Vcc=1.8V Icc vs. temp. Isink=2mA Figure 7. Vref vs. temp. Vcc=1.8V 1.235 400 350 300 250 200 150 100 50 0 1.23 Vref (V) Icc (µA) 85°C 350 1.6 1.4 1.2 1 0.8 0.6 0.4 0.2 0 Icc (µA) dVref/dVcc (mV) dVref/dVcc vs. temp. Isink=2mA -40°C 1.225 1.22 -40°C -20°C 0°C 25°C 50°C Tem perature (°C) Vcc=1.5V 5/8 25°C 50°C Vcc=10V Vcc=1.8V Figure 6. 0°C Tem perature (°C) Te m perature (°C) Figure 4. Vref vs. temp. Isink=2mA Vcc=10V 85°C 1.215 -40°C -20°C 0°C 25°C 50°C 85°C Tem perature (°C) Isink=20mA Isink=0.5mA Electrical Characteristics dVref/dIsink vs. temp. Vcc=1.8V 8 7 6 5 4 3 2 1 0 -40°C -20°C 0°C 25°C 50°C 85°C Figure 10. Vsat vs. temp. Vcc=1.8V 100 Vsat (mV) 80 60 40 20 0 0°C 25°C 50°C Tem perature (°C) Isink=20mA 0.8 0.7 0.6 0.5 0.4 0.3 0.2 0.1 0 -40°C -20°C 0°C 25°C 50°C Isink 0.1 to 10mA Isink 0.5 to 20mA -40°C -20°C Iref vs. temp. Vcc=1.8V Tem perature (°C) Tem perature (°C) 6/8 Figure 9. Iref (µA) dVref/DIsink (mV) Figure 8. TS4431 Isink=5mA 85°C 85°C TS4431 4 Package Mechanical Data Package Mechanical Data In order to meet environmental requirements, ST offers these devices in ECOPACK® packages. These packages have a Lead-free second level interconnect. The category of second level interconnect is marked on the package and on the inner box label, in compliance with JEDEC Standard JESD97. The maximum ratings related to soldering conditions are also marked on the inner box label. ECOPACK is an ST trademark. ECOPACK specifications are available at: www.st.com. SOT23-5L Package SOT23-5L MECHANICAL DATA mm. mils DIM. MIN. TYP MAX. MIN. TYP. MAX. A 0.90 1.45 35.4 57.1 A1 0.00 0.15 0.0 5.9 A2 0.90 1.30 35.4 51.2 b 0.35 0.50 13.7 19.7 C 0.09 0.20 3.5 7.8 D 2.80 3.00 110.2 118.1 E 2.60 3.00 102.3 118.1 E1 1.50 1.75 59.0 68.8 e 0 .95 37.4 e1 1.9 74.8 L 0.35 0.55 13.7 21.6 7/8 Revision History 5 TS4431 Revision History Date Revision Changes March 2005 1 First release corresponding to Preliminary Data version of datasheet. Nov. 2005 2 First release of fully mature product data sheet. Information furnished is believed to be accurate and reliable. However, STMicroelectronics assumes no responsibility for the consequences of use of such information nor for any infringement of patents or other rights of third parties which may result from its use. No license is granted by implication or otherwise under any patent or patent rights of STMicroelectronics. Specifications mentioned in this publication are subject to change without notice. This publication supersedes and replaces all information previously supplied. STMicroelectronics products are not authorized for use as critical components in life support devices or systems without express written approval of STMicroelectronics. The ST logo is a registered trademark of STMicroelectronics. All other names are the property of their respective owners © 2005 STMicroelectronics - All rights reserved STMicroelectronics group of companies Australia - Belgium - Brazil - Canada - China - Czech Republic - Finland - France - Germany - Hong Kong - India - Israel - Italy - Japan Malaysia - Malta - Morocco - Singapore - Spain - Sweden - Switzerland - United Kingdom - United States of America www.st.com 8/8