LR8_07

LR8 High Input Voltage Adjustable 3-Terminal Linear Regulator Features ► ► ► ► ► ► 13.2V to 450V input voltage range Adjustable 1.20V to 440V output regulation 5% output voltage tolerance Output current limiting 10µA typical ADJ current Internal junction temperature limiting General Description The Supertex LR8 is a high voltage, low output current, adjustable linear regulator. It has a wide operating input voltage range of 13.2V to 450V. The output voltage can be adjusted from 1.20V to 440V provided that the input voltage is at least 12V greater than the output voltage. The output voltage can be adjusted by means of two external resistors R1 and R2 as shown in the typical application circuits. The LR8 regulates the voltage difference between VOUT and ADJ pins to a nominal value of 1.20V. The 1.20V is amplified by the external resistor ratio R1 and R2. An internal constant bias current of typically 10µA is connected to the ADJ pin. This increases VOUT by a constant voltage of 10µA times R2. The LR8 has current limiting and temperature limiting. The output current limit is typically 20mA and the minimum temperature limit is 125°C. An output short circuit current will therefore be limited to 20mA. When the junction temperature reaches its temperature limit, the output current and/or output voltage will decrease to keep the junction temperature from exceeding its temperature limit. For SMPS start-up circuit applications, the LR8 turns off when an external voltage greater than the output voltage of the LR8 is applied to VOUT of the LR8. To maintain stability, a bypass capacitor of 1.0µF or larger and a minimum DC output current of 500µA are required. The device is available in TO-243AA (SOT-89), TO-252 (DPAK), and TO-92 packages. Applications ► ► ► ► ► ► Off-line SMPS startup circuits Adjustable high voltage constant current source Industrial controls Motor controls Battery chargers Power supplies Typical Application Circuit * VOUT VIN VIN VOUT ADJ R1 C2 R2 RLOAD LR8 C1 *Required for conditions where VIN is less than VOUT. LR8 Ordering Information DEVICE LR8 Package Option TO-243AA LR8N8-G TO-252 LR8K4-G TO-92 LR8N3-G -G indicates package is RoHS compliant (‘Green’) Absolute Maximum Ratings Parameter VIN input voltage (voltages ref to ADJ) Output voltage range Operating ambient temperature range Operating junction temperature range Storage temperature range Value -0.5V to +480V -0.5V to +470V -40°C to +85°C -40°C to +125°C -65°C to +150°C Pin Configurations VOUT VOUT VIN VOUT ADJ VIN ADJ VIN VOUT ADJ Stresses beyond those listed under “Absolute Maximum Ratings” may cause permanent damage to the device. These are stress ratings only, and functional operation of the device at these or any other conditions beyond those indicated in the operational sections of the specifications is not implied. Exposure to absolute maximum rating conditions for extended periods may affect device reliability. TO-243AA (SOT-89) TO-252 (D-PAK) (top view) (top view) TO-92 (front view) Product Marking Product marking for TO-243AA: LR8 where = 2-week alpha date code Electrical Characteristics (Test conditions unless otherwise specified: Symbol VIN - VOUT VOUT VOUT ΔVOUT ΔVOUT ΔVOUT IOUT IOUT IOUT IADJ C2 DVOUT/DVIN TLIMIT Parameter Input to output voltage difference Overall output voltage regulation Overall output voltage regulation Line regulation Load regulation Temperature regulation Output current limit Output current limit Minimum output current Adjust output current Minimum output load capacitance Ripple rejection ratio Junction temperature limit Min 12 1.14 375 -1 10 5 1 50 125 Typ 1.20 400 0.003 1.4 0.3 10 60 - -40°C < TA < 85°C.) Max 450 1.26 425 0.01 3.0 +1 30 0.5 0.5 15 - Units Conditions V V V %/V % % mA mA mA µA µF dB °C --13.2V < VIN< 400V, R1 = 2.4KΩ, R2 = 0 R1 = 2.4KΩ, R2 = 782KΩ 17V < VIN< 400V, VOUT = 5V, IOUT = 0.5mA VIN = 17V, VOUT = 5V, 0.5mA 125°C, VIN - VOUT = 450V Includes R1 and load current ----120Hz, VOUT = 5V --- 2 LR8 Thermal Characteristics Package TO-92 TO-243AA TO-252 Power Dissipation @ TA = 25°C 0.74W 1.6W 2.5W θJC °C/W 125 15 6.25 θJA °C/W 170 78† 50† †Mounted on FR4 board, 25mm x 25mm x 1.57mm. Significant PD increase possible on ceramic substrate. Functional Block Diagram VIN Pass Element LR8 VOUT Overtemp & Overcurrent 1.2V 10µA ADJ Typical Application Circuits Figure 1: High Input Voltage, 5.0V Output Linear Regulator * VOUT = 5.0V VIN = 17V to 450V VIN VOUT ADJ LR8 C1 R2 18.2KΩ 1% R1 6.04KΩ 1% C2 1.0µF RLOAD ≤16.5KΩ * Required for conditions where VIN is less than VOUT R2 VOUT = 1.20V 1+ R1 + IADJ R2 3 LR8 Typical Application Circuits Figure 2: SMPS Start-Up Circuit VIN = (VOUT + 12V) to 450V + VAUXILIARY VOUT1 VIN VOUT ADJ + VOUT2 VCC FB - LR8 PWM IC Figure 3: High Voltage Adjustable Constant Current Source IOUT = R + VIN VOUT ADJ VIN = (VOUT + 12V) to 450V 1.20V R LR8 1.0µF LOAD - 4 LR8 Typical Performance Curves Temperature Variation 1.30 VIN VOUT = 1.2V VOUT (V) 1.25 LR8 ADJ 12V 2.4KΩ 1.0µF 1.20 1.15 1.10 1.05 1.00 -50 -25 0 25 50 75 100 125 T(junction) ( OC) Adjustment Current 12 11 VIN VOUT = 1.2V IADJ (µA) LR8 12V, 200V, 400V ADJ 2.4KΩ I ADJ 10 VIN = 400V 9 VIN = 12V 1.0ΩF 8 VIN = 200V 7 6 -50 -25 0 25 50 75 100 125 T(junction) (OC) Load Regulation 5.2 V IN V OUT = 5.0V IOUT 5.1 LR8 ADJ 25V 18.2KΩ ±1% VOUT (V) RLOAD 6.04KΩ ±1% 1.0µF 5.0 4.9 4.8 0 2 4 6 8 10 IOUT (mA) 5 LR8 Typical Performance Curves (cont.) VOUT vs. VIN 6 VIN VOUT = 5.0V 5 LR8 ADJ 0V to 50V 18.2KΩ ±1% 6.04KΩ ±1% 1.0µF 1KΩ VOUT (V) 4 3 2 1 0 0 10 20 30 40 50 VIN (V) Ripple Rejection -65 VIN LR8 ADJ VOUT = 5.0V IOUT Ripple Rejection Ratio (dB) -64 20VP-P @ 60Hz 65V 6.04KΩ ±1% 1.0µF RLOAD 18.2KΩ ±1% -63 -62 -61 -60 0 2 4 6 8 10 I OUT (mA) 30 25 l c l (m A ) 20 15 10 -40 -20 0 20 40 60 80 100 Temperature (°C) 6 LR8 Typical Performance Curves (cont.) LR8 ± Ω Ω ± Ω Ω Load Transient Response LR8 ± Ω Ω ± Ω Line Transient Response Line Power Up Transient Line Power Down Transient 7 LR8 3-Lead TO-243AA (SOT-89) Package Outline (N8) 4.50 ± 0.10 1.72 ± 0.10 0.40 ± 0.05 Exclusion Zone 1.50 ± 0.10 4.10 ± 0.15 2.45 ± 0.15 2.21 ± 0.08 No Vias/Traces in this area. Shape of pad may vary. 1.05 ± 0.15 0.42 ± 0.06 1.50 BSC 3.00 BSC 0.5 ± 0.06 Top View Side View Bottom View Notes: All dimensions are in millimeters; all angles in degrees. 3-Lead TO-252 (D-PAK) Package Outline (K4) 0.250 - 0.265 0.195 -0.215 0.035 - 0.050 0.018 - 0.035 0.086 - 0.094 4 0O - 15O 0.370 - 0.410 0.240 ± 0.005 0.040 MAX 0.005 MAX 1 2 3 0.047 - 0.070 0.108 REF 0O - 10O 0.018 - 0.024 0.20 BSC 0.030 - 0.045 0.025 - 0.035 0.170 MIN 0.090 BSC 4 Cutouts may not be present 0.205 MIN Notes: All dimensions in inches; angles in degrees 3 2 1 8 LR8 3-Lead TO-92 Package Outline (N3) 0.135 MIN 0.125 - 0.165 0.080 - 0.105 1 2 3 Top View 0.175 - 0.205 0.170 - 0.210 123 Seating Plane 0.500 MIN 0.014 - 0.022 0.014 - 0.022 0.045 - 0.055 0.095 - 0.105 Front View Side View Notes: All dimensions are in millimeters; all angles in degrees. (The package drawing(s) in this data sheet may not reflect the most current specifications. For the latest package outline information go to http://www.supertex.com/packaging.html.) Doc.# DSFP-LR8 A121806 9