LR12LG

LR12 LR12 High Input Voltage Adjustable 3-Terminal Linear Regulator Features ❏ ❏ ❏ ❏ ❏ ❏ ❏ ❏ 13.2V to 100V Input Voltage Range Stable with 100nF output capacitor Adjustable 1.20V to 88V output regulation 5% reference voltage tolerance Output current limiting, 50mA min. 10µA typical ADJ current Over temperature protection Available in 3 different packages General Description The Supertex LR12 is a high voltage, low output current, adjustable linear regulator. It has a wide operating input voltage range of 13.2V to 100V. The output voltage can be adjusted from 1.20V to 88V 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 LR12 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 LR12 has current limiting and temperature limiting. The output current limit is 100mA maximum and the minimum temperature limit is 125°C. An output short circuit current will therefore be limited to 100mA maximum. 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 LR12 turns off when an external voltage greater than the output voltage of the LR12 is applied to VOUT of the LR12. To maintain stability, a bypass capacitor of 100nF or larger and a minimum DC output current of 500µA are required. The device is available in TO-92, SO-8, and TO-252 (D-PAK) packages. Applications ❏ ❏ ❏ ❏ ❏ ❏ ❏ ❏ ❏ DC/DC SMPS startup circuits Adjustable high voltage constant current sources Industrial Controls Motor Controls Battery Powered Systems Power Supplies Telecom Applications LED Drivers Automotive Applications LR12 Typical Application * VOUT 1.2V to 88V VIN 13.2V to 100V C1 VIN V ADJ OUT LR12 R1 C2 RLOAD R2 *Required for conditions where VIN is less than VOUT. A081605 A081605 1 LR12 Ordering Information Package Options SO-8 LR12LG LR12LG-G TO-2521 LR12K4 LR12K4-G TO-92 LR12N3 LR12N3-G Notes: 1. TO-252 supplied on 2000 piece carrier tape reels only -G indicates package is RoHS compliant “Green” Pin Configurations VOUT ADJ NC 1 2 3 4 8 7 6 5 VOUT VOUT VOUT VOUT VIN ADJ Absolute Maximum Ratings VIN-ADJ VOUT-ADJ VIN – VOUT Operating Ambient Temperature Range Operating Junction Temperature Range Storage Temperature Range -0.5V to +120V -10V to +10V -0.5V to +120V -40°C to +85°C NC VIN SO-8 TO-92 TO-252 (D-PAK) -65°C to +150°C Electrical Characteristics Test conditions unless otherwise specified: -40°C < TA < 85°C. Symbol VIN - VOUT VOUT ∆VOUT ∆VOUT ∆VOUT IOUT IOUT IOUT IADJ C2 Parameter Input to Output Voltage Difference 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 0.5 5 100 50 125 60 10 15 -1 50 Min 12 1.14 1.20 0.003 1.4 Typ Max 98.8 1.26 0.03 3.0 +1 100 0.5 Units V V %/V % % mA mA mA µA nF dB °C 120Hz, VOUT = 5V 13.2V