MC7800, MC7800A, NCV A Positive Voltage Regulators

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MC7800, MC7800A, NCV7805 A Positive Voltage Regulators These voltage regulators are monolithic integrated circuits designed as fixed voltage regulators for a wide variety of applications including

1 MC7800, MC7800A, NCV7805 A Positive Voltage Regulators These voltage regulators are monolithic integrated circuits designed as fixed voltage regulators for a wide variety of applications including local, on card regulation. These regulators employ internal current limiting, thermal shutdown, and safe area compensation. With adequate heatsinking they can deliver output currents in excess of A. Although designed primarily as a fixed voltage regulator, these devices can be used with external components to obtain adjustable voltages and currents. Output Current in Excess of A No External Components Required Internal Thermal Overload Protection Internal Short Circuit Current Limiting Output Transistor Safe Area Compensation Output Voltage Offered in 2% and 4% Tolerance Available in Surface Mount 3, DPAK 3 and Standard 3 Lead Transistor Packages NCV Prefix for Automotive and Other Applications Requiring Site and Control Changes Pb Free Packages are Available MAXIMUM RATINGS (T A = 25 C, unless otherwise noted) Pin Ground 3. Output TO T SUFFIX CASE 221A Heatsink surface connected to Pin 2. 3 D2T SUFFIX CASE Heatsink surface (shown as terminal 4 in case outline drawing) is connected to Pin STANDARD APPLICATION DPAK 3 DT SUFFIX CASE 369C Value Unit MC78XX Output Rating Symbol 369C 221A 936 Voltage ( V) (24 V) V I 35 Vdc C in * 0.33 F C O ** Power Dissipation P D Internally Limited W Thermal Resistance, Junction to Ambient Thermal Resistance, Junction to Case Storage Junction Temperature Range R JA Figure 14 C/W R JC C/W T stg 65 to +1 C Operating Junction Temperature T J +1 C Maximum ratings are those values beyond which device damage can occur. Maximum ratings applied to the device are individual stress limit values (not normal operating conditions) and are not valid simultaneously. If these limits are exceeded, device functional operation is not implied, damage may occur and reliability may be affected. *This device series contains ESD protection and exceeds the following tests: Human Body Model 2000 V per MIL_STD_883, Method Machine Model Method 200 V. A common ground is required between the input and the output voltages. The input voltage must remain typically V above the output voltage even during the low point on the input ripple voltage. XX, These two digits of the type number indicate nominal voltage. * C in is required if regulator is located an appreciable distance from power supply filter. ** C O is not needed for stability; however, it does improve transient response. Values of less than 0.1 F could cause instability. ORDERING INFORMATION See detailed ordering and shipping information in the package dimensions section on page 22 of this data sheet. DEVICE MARKING INFORMATION See general marking information in the device marking section on page 28 of this data sheet. Semiconductor Components Industries, LLC, 2005 April, 2005 Rev Publication Order Number: MC7800/D

2 R k D1 Zener Q7 R k R k Q8 LAT Q17 Q9 2 Q6 Q5 2 MC7800 R11 15 k R24 LAT 3 A Q18 Q10 Q15 C3 R R P Q12 R Q19 R D2 Zener R k R10 33 (3316ACT) R14 k R R k R k R k Q20 R V in R k R k R k R30 18 k V out 5.01 Sense R k Q14 R6 k R5 4.5 k C2 3.0 P 6 Q13 Q1 N+ Q4 Q2 Q16 4 Diode C1 30 P R9 3.0 k Q3 SUB Q11 2 R R7 14 k R3 1.8 k R8 5.0 k This device contains 22 active transistors. Figure 1. Representative Schematic Diagram 2

3 ELECTRICAL CHARACTERISTICS (V in = 19 V, I O = 0 ma, T J = T low to T high (Note 16), unless otherwise noted) MC7812B MC7812C Characteristic Symbol Min Typ Max Min Typ Max Unit Output Voltage (T J = 25 C) V O Vdc Output Voltage (5.0 ma I O A, P D 15 W) V O Vdc 14.5 Vdc V in 27 Vdc Vdc V in 27 Vdc Line Regulation, T J = 25 C (Note 17) Reg line mv 14.5 Vdc V in 30 Vdc Vdc V in 22 Vdc Vdc V in 27 Vdc, I O = A 48 Load Regulation, T J = 25 C (Note 17) Reg load mv 5.0 ma I O 1.5 A Quiescent Current I B ma Quiescent Current Change I B ma 14.5 Vdc V in 30 Vdc, I O = A, T J = 25 C Vdc V in 30 Vdc ma I O A Ripple Rejection RR db 15 Vdc V in 25 Vdc, f = 120 Hz Dropout Voltage (I O = A, T J = 25 C) V I V O Vdc Output Noise Voltage (T A = 25 C) V n V/V O 10 Hz f 100 khz Output Resistance f = khz r O m Short Circuit Current Limit (T A = 25 C) I SC A V in = 35 Vdc Peak Output Current (T J = 25 C) I max A Average Temperature Coefficient of Output Voltage TCV O mv/ C 16.T low =0 C for MC78XXAC, C T high = +125 C for MC78XXAC, C, NCV7805 = C for MC78XXB, MC78XXAB, NCV Load and line regulation are specified at constant junction temperature. Changes in V O due to heating effects must be taken into account separately. Pulse testing with low duty cycle is used. 11

4 I MC7800, MC7800A, NCV T J = C 80, OUTPUT CURRENT (A) IO T J = 85 C T J = 125 C T J = 0 C T J = 25 C RR, RIPPLE REJECTION (db) PART #М V in MC7805C = 10 V MC7806C = 11 V MC7808C = 14 V MC7812C = 19 V MC7815C = 23 V MC7818C = 27 V MC7824C = 33 V f = 120 Hz I O = 20 ma V in = V(RMS) V in V out, INPUT/OUTPUT VOLTAGE DIFFERENTIAL (V) Figure 2. Peak Output Current as a Function of /Output Differential Voltage (MC78XXC, AC, B) V O, OUTPUT VOLTAGE (V) Figure 3. Ripple Rejection as a Function of Output Voltages (MC78XXC, AC, B) 80 RR, RIPPLE REJECTION (db) MC78XXB, C, AC V in = 8.0 V to 18 V I O = 0 ma f = 120 Hz T A = 25 C O, OUTPUT VOLTAGE (V) V V in = 20 V I O = 5.0 ma f, FREQUENCY (khz) Figure 4. Ripple Rejection as a Function of Frequency (MC78XXC, AC, B) T J, JUNCTION TEMPERATURE ( C) Figure 5. Output Voltage as a Function of Junction Temperature (MC7805C, AC, B), OUTPUT IMPEDANCE (mм) O Ω Z f = 120 Hz I O = 0 ma C L = 0 F B, QUIESCENT CURRENT (ma) V in = 10 V V O = 5.0 V I L = 20 ma V O, OUTPUT VOLTAGE (V) T J, JUNCTION TEMPERATURE ( C) Figure 6. Output Impedance as a Function of Output Voltage (MC78XXC, AC, B) Figure 7. Quiescent Current as a Function of Temperature (MC78XXC, AC, B) 19

5 APPLICATIONS INFORMATION Design Considerations The MC7800 Series of fixed voltage regulators are designed with Thermal Overload Protection that shuts down the circuit when subjected to an excessive power overload condition, Internal Short Circuit Protection that limits the maximum current the circuit will pass, and Output Transistor Safe Area Compensation that reduces the output short circuit current as the voltage across the pass transistor is increased. In many low current applications, compensation capacitors are not required. However, it is recommended that the regulator input be bypassed with a capacitor if the regulator is connected to the power supply filter with long wire lengths, or if the output load capacitance is large. An input bypass capacitor should be selected to provide good high frequency characteristics to insure stable operation under all load conditions. A 0.33 F or larger tantalum, mylar, or other capacitor having low internal impedance at high frequencies should be chosen. The bypass capacitor should be mounted with the shortest possible leads directly across the regulators input terminals. Normally good construction techniques should be used to minimize ground loops and lead resistance drops since the regulator has no external sense lead. MC F R The MC7800 regulators can also be used as a current source when connected as above. In order to minimize dissipation the MC7805C is chosen in this application. Resistor R determines the current as follows: I O Constant Current to Grounded Load 0.33 F MC7805 k MC1741G 10 k Output 0.1 F I 5.0 V O R I B I B 3.2 ma over line and load changes. For example, a A current source would require R to be a 5.0, 10 W resistor and the output voltage compliance would be the input voltage less 7.0 V. Figure 8. Current Regulator V O = 7.0 V to 20 V V IN = V O V The addition of an operational amplifier allows adjustment to higher or intermediate values while retaining regulation characteristics. The minimum voltage obtainable with this arrangement is V greater than the regulator voltage. Figure 9. Adjustable Output Regulator R Source MJ2955 or Equiv. R Source R SC MJ2955 or Equiv F 0.33 F 10 F R F MC78XX F Output 10 F R 2N6049 or Equiv. F MC78XX Output XX = 2 digits of type number indicating voltage. The MC7800 series can be current boosted with a PNP transistor. The MJ2955 provides current to 5.0 A. Resistor R in conjunction with the V BE of the PNP determines when the pass transistor begins conducting; this circuit is not short circuit proof. /output differential voltage minimum is increased by V BE of the pass transistor. XX = 2 digits of type number indicating voltage. The circuit of Figure 10 can be modified to provide supply protection against short circuits by adding a short circuit sense resistor, R SC, and an additional PNP transistor. The current sensing PNP must be able to handle the short circuit current of the three terminal regulator. Therefore, a four ampere plastic power transistor is specified. Figure 10. Current Boost Regulator Figure 11. Short Circuit Protection 20

6 D, POWER DISSIPATION (W) P HS = 0 C/W HS = 15 C/W No Heatsink HS = 5 C/W JC = 5 C/W JA = 65 C/W T J(max) = 1 C in V out, INPUT OUTPUT VOLTAGE DIFFERENTIAL (V) V I O = A I O = 0 ma I O = 200 ma I O = 20 ma I O = 0 ma V O = 2% of V O Extended Curve for MC78XXB T A, AMBIENT TEMPERATURE ( C) Figure 12. Worst Case Power Dissipation versus Ambient Temperature (Case 221A) T J, JUNCTION TEMPERATURE ( C) Figure 13. Output Differential as a Function of Junction Temperature (MC78XXC, AC, B) R θja, THERMAL RESISTANCE JUNCTION-TO-AIR ( C/W) Free Air Mounted Vertically Minimum Size Pad P D(max) for T A = C R JA oz. Copper L L, LENGTH OF COPPER (mm) L P D, MAXIMUM POWER DISSIPATION (W) Figure 14. Thermal Resistance and Maximum Power Dissipation versus P.C.B. Copper Length R θja, THERMAL RESISTANCE JUNCTION TO AIR ( C/W) Free Air Mounted Vertically Minimum Size Pad P D(max) for T A = C R JA L, LENGTH OF COPPER (mm) 2.4 oz. Copper L 1.6 L 1.2 Figure 15. DPAK Thermal Resistance and Maximum Power Dissipation versus P.C.B. Copper Length , MAXIMUM POWER DISSIPATION (W) P D 21

7 ORDERING INFORMATION Device Nominal Voltage Operating Package Shipping Temperature Range MC7809ACT 9.0 V T = 0 C to +125 C TO 220 MC7809ACTG TO 220 MC7809BT T = C to +125 C TO 220 MC7809BTG TO 220 MC7809CD2T T = 0 C to +125 C MC7809CD2TG MC7809CD2TR4 800 / Tape & Reel MC7809CD2TR4G 800 / Tape & Reel MC7809CT TO 220 MC7809CTG TO 220 MC7812ABD2T 12 V T = C to +125 C MC7812ABD2TG MC7812ABD2TR4 800 / Tape & Reel MC7812ABD2TR4G 800 / Tape & Reel MC7812ABT TO 220 MC7812ABTG TO 220 MC7812ACD2T T = 0 C to +125 C MC7812ACD2TG MC7812ACD2TR4 800 / Tape & Reel MC7812ACD2TR4G 800 / Tape & Reel MC7812ACT TO 220 MC7812ACTG TO 220 MC7812BD2T T = C to +125 C MC7812BD2TG MC7812BD2TR4 800 / Tape & Reel MC7812BD2TR4G 800 / Tape & Reel MC7812BDT DPAK 75 Units / Rail MC7812BDTG DPAK 75 Units / Rail For information on tape and reel specifications, including part orientation and tape sizes, please refer to our Tape and Reel Packaging Specifications Brochure, BRD8011/D. *NCV devices: T low = C, T high = +125 C. Guaranteed by design. NCV prefix is for automotive and other applications requiring site and change control. 25

8 PACKAGE DIMENSIONS 3 D2T SUFFIX CASE ISSUE B B K F J D (0.254) M T C A G S OPTIONAL CHAMFER H N R T E M L V TERMINAL 4 P U SOLDERING FOOTPRINT* NOTES: 1. DIMENSIONING AND TOLERANCING PER ANSI Y14.5M, CONTROLLING DIMENSION: INCH. 3. TAB CONTOUR OPTIONAL WITHIN DIMENSIONS A AND K. 4. DIMENSIONS U AND V ESTABLISH A MINIMUM MOUNTING SURFACE FOR TERMINAL DIMENSIONS A AND B DO NOT INCLUDE MOLD FLASH OR GATE PROTRUSIONS. MOLD FLASH AND GATE PROTRUSIONS NOT TO EXCEED (0.635) MAXIMUM. INCHES MILLIMETERS DIM MIN MAX MIN MAX A B C D E F REF REF G BSC 2.5 BSC H J MAX MAX K 0.0 REF REF L M N P R 5 REF 5 REF S REF REF U MIN MIN V 0.2 MIN 6.3 MIN SCALE 3:1 mm inches *For additional information on our Pb Free strategy and soldering details, please download the ON Semiconductor Soldering and Mounting Techniques Reference Manual, SOLDERRM/D. 30

MC7800, MC7800A, NCV A Positive Voltage Regulators

MC7800, MC7800A, NCV A Positive Voltage Regulators MC7800, MC7800A, NCV7805 1.0 A Positive Voltage Regulators These voltage regulators are monolithic integrated circuits designed as fixedvoltage regulators for a wide variety of applications including local,