www.fairchildsemi.com LM79M05 3-Terminal 0.5A Negative Voltage Regulator Features Description • • • • • • The LM79M05 of 3-Terminal medium current negative voltage regulator is monolithic integrated circuits designed as fixed voltage regulator. This regulator employs internal current limiting, thermal shutdown and safe area compensation making them essentially indestructible. No External Components Required Output Current in Excess of 0.5A Internal Thermal Overload Internal Short Circuit Current Limiting Output Transistor Safe Area Compensation Output Voltages of -5V TO-220 (Single Gauge) 1 1. GND 2. Input 3. Output Schematic Diagram GND R6 R2 Q15 Q13 Q8 D1 D2 D3 R10 R11 R9 Q12 R3 R1 R4 R15 Q14 Q10 Q9 R14 R12 Q11 R5 R8 Q16 R13 R7 D5 Q18 Q2 Q17 Q3 R16 Q24 Q25 OUT Q5 Q1 R17 Q4 Q6 D4 Q7 C1 Q19 R24 R25 Q20 R19 R18 C2 Q23 Q26 R20 Q21 Q22 R21 R22 Q27 R23 IN Rev. 1.0.5 ©2012 Fairchild Semiconductor Corporation LM79M05 Absolute Maximum Ratings Parameter Symbol Value Unit VI -35 V Thermal Resistance Junction-Cases RJC 5 C/W Thermal Resistance Junction-Air RJA 65 C/W Operating Temperature Range TOPR 0 ~ +125 C Storage Temperature Range TSTG -65 ~ +150 C Input Voltage(for VO = -5V) Electrical Characteristics (LM79M05) (Refer to test circuit, 0CTJ +125C, lO =350mA, VI = -10V,unless otherwise specified, CI =0.33F,CO=0.1F) Parameter Output Voltage Symbol VO Conditions Min. Typ. Max. TJ = +25C -4.8 -5 -5.2 IO = 5mA to 350mA VI = -7V to -25V -4.75 -5 -5.25 VI = -7V to -25V - 7.0 50 VI = -8V to -25V - 2.0 30 Unit V Line Regulation (Note1) VO TJ =+25C Load Regulation (Note1) VO IO = 5mA to 500mA TJ = +25C - 30 100 mV TJ = +25C - 3.0 6.0 mA IO = 5mA to 350mA - - 0.4 IO = 200mA VI = -8V to -25V - - 0.4 IO = 5mA - -0.2 - mV/C - 40 - V 54 60 - dB Quiescent Current Quiescent Current Change Output Voltage Drift IQ IQ Vo/T mV mA Output Noise Voltage VN f = 10Hz, 100kHz TA = +25C Ripple Rejection RR f = 120Hz VJ = -8 to -18V Dropout Voltage VD TJ =+25C, IO = 500mA - 1.1 - V Short Circuit Current ISC TJ = +25C, VI = -35V - 140 - mA Peak Current IPK TJ = +25C - 650 - mA Note: 1. Load and line regulation are specified at constant junction temperature. Change in VO due to heating effects must be taken into account separately. Pulse testing with low duty is used. 2 LM79M05 Typical Performance Characteristics 0.0 VD - Dropout Voltage [V] VIN = -10V VO = -5V -0.2 IOUT = 0mA -0.4 IOUT = 200mA -0.6 IOUT = 300mA IOUT = 100mA -0.8 -1.0 IOUT = 400mA -1.2 0 25 50 75 IOUT = 500mA 100 125 150 o TA - Temperature [ C] Figure 1. Dropout Voltage 3 LM79M05 Typical Applications 2 VI 3 LM79M05 VO 1 1.0uF 2.0uF Figure 2. Fixed Output Regulator VI VO LM79M05 R1 C1 _ 2.2uF SOLID + TANTALUM _ 1uF + _ + C2 25uF C3 SOLID TANTALUM R2 Figure 3. Variable Output Notes: 1. Required for stability. For value given, capacitor must be solid tantalum. 25F aluminum electrolytic may be substituted. 2. C2 improves transient response and ripple rejection. Do not increase beyond 50F. 4 LM79M05 Mechanical Dimensions Package Dimensions in millimeters TO-220 [ SINGLE GAUGE ] 5 LM79M05 Ordering Information Product Number Package Operating Temperature LM79M05CT TO-220 (Single Gauge) 0 ~ +125C DISCLAIMER FAIRCHILD SEMICONDUCTOR RESERVES THE RIGHT TO MAKE CHANGES WITHOUT FURTHER NOTICE TO ANY PRODUCTS HEREIN TO IMPROVE RELIABILITY, FUNCTION OR DESIGN. FAIRCHILD DOES NOT ASSUME ANY LIABILITY ARISING OUT OF THE APPLICATION OR USE OF ANY PRODUCT OR CIRCUIT DESCRIBED HEREIN; NEITHER DOES IT CONVEY ANY LICENSE UNDER ITS PATENT RIGHTS, NOR THE RIGHTS OF OTHERS. LIFE SUPPORT POLICY FAIRCHILD’S PRODUCTS ARE NOT AUTHORIZED FOR USE AS CRITICAL COMPONENTS IN LIFE SUPPORT DEVICES OR SYSTEMS WITHOUT THE EXPRESS WRITTEN APPROVAL OF THE PRESIDENT OF FAIRCHILD SEMICONDUCTOR CORPORATION. As used herein: 1. Life support devices or systems are devices or systems which, (a) are intended for surgical implant into the body, or (b) support or sustain life, and (c) whose failure to perform when properly used in accordance with instructions for use provided in the labeling, can be reasonably expected to result in a significant injury of the user. 2. A critical component in any component of a life support device or system whose failure to perform can be reasonably expected to cause the failure of the life support device or system, or to affect its safety or effectiveness. www.fairchildsemi.com 7/18/12 0.0m 001 Stock#DS903555 2012 Fairchild Semiconductor Corporation