BA51W12SAT Regulator ICs Dual output voltage regulator with power saving BA51W12SAT The BA51W12SAT is a general-purpose, low saturation power supply with two outputs : 9V, 1A and 5V, 500mA. The IC is available in a compact TO220FP-5 package. The outputs can be turned off during the power saving state with the built-in switch. Also built in the IC is an overcurrent protection circuit, an overvoltage protection circuit, and a thermal shutdown circuit. !Applications Car audio systems, VCRs, facsimiles, air conditioners, and other household and industrial equipment !Features 1) Minimum I / O voltage differential is 0.5V or less. 2) Built-in protection circuits against overcurrent, over voltage, and overheat. 3) Available in a compact TO220FP-5 package (pins are bendable). 4) Zero power saving current. (Typ.) !Absolute maximum ratings (Ta=25°C) Parameter Symbol Power supply voltage VCC Power dissipation Pd Limits Unit 35 V 2000∗1 mW Topr −40~+85 °C Storage temperature Tstg −55~+150 °C Peak applied voltage VCCPeak 50∗2 V Operating temperature ∗1 Reduced by 16mW for each increase in Ta of 1°C over 25°C. ∗2 Applied time is less than 200 ms (tr≥1ms). tr≥1ms 50V 35V Max.200ms 0V !Recommended operating conditions (Ta=25°C) Parameter Power supply voltage Symbol Min. Typ. Max. Unit VCC 10 14 25 V BA51W12SAT Regulator ICs !Measurement circuits OUT1 VCC OUT2 CTL GND 0.33µ + 22µ V VCC 5V + IO1 22µ V IO2 VCC=14V, IO1=500mA when measuring output voltage 1 VCC=14V, IO2=350mA when measuring output voltage 2 VCC=10→25V, IO1=500mA when measuring input stability 1 VCC=6→25V, IO2=350mA when measuring input stability 2 VCC=14V, IO1=5mA→1A when measuring load reguration 1 VCC=14V, IO2=5mA→500mA when measuring load reguration 2 VCC=14V when measuring output current capacity 1 VCC=14V when measuring output current capacity 2 Fig.1 Circuit for measuring output voltage, input stability, load regulation, and output current capacity VCC OUT1 10Ω5W VCC CTL + GND OUT2 + 22µ 0.33µ 100µ υ + eIN=1Vrms f=120Hz 5V 500mA 22µ υ 350mA VCC=14V, IO1=500mA when meauring the ripple rejection ratio 1 VCC=14V, IO2=350mA when meauring the ripple rejection ratio 2 Fig.2 Circuit for measuring ripple rejection ratio BA51W12SAT Regulator ICs !Measurement circuits OUT1 VCC OUT2 CTL GND 0.33µ + 22µ V VCC 5V + IO1 22µ V IO2 VCC=14V, IO1=500mA when measuring output voltage 1 VCC=14V, IO2=350mA when measuring output voltage 2 VCC=10→25V, IO1=500mA when measuring input stability 1 VCC=6→25V, IO2=350mA when measuring input stability 2 VCC=14V, IO1=5mA→1A when measuring load reguration 1 VCC=14V, IO2=5mA→500mA when measuring load reguration 2 VCC=14V when measuring output current capacity 1 VCC=14V when measuring output current capacity 2 Fig.1 Circuit for measuring output voltage, input stability, load regulation, and output current capacity VCC OUT1 10Ω5W VCC CTL + GND OUT2 + 22µ 0.33µ 100µ υ + eIN=1Vrms f=120Hz 5V 500mA 22µ υ 350mA VCC=14V, IO1=500mA when meauring the ripple rejection ratio 1 VCC=14V, IO2=350mA when meauring the ripple rejection ratio 2 Fig.2 Circuit for measuring ripple rejection ratio BA51W12SAT Regulator ICs V V OUT1 VCC CTL OUT2 GND + 22µ V 0.33µ VCC + 500mA 22µ 5V V 350mA VCC=8.55V when measuring minimum I / O voltage difference 1 VCC=4.75V when measuring minimum I / O voltage difference 2 Fig.3 Circuit for measuring minimum I / O voltage difference OUT1 VCC A CTL GND OUT2 + 0.33µ VCC + 22µ 22µ 5V VCC=14V, IO=0mA, VCTL=5V when measuring bias current VCC=14V, IO=0mA, VCTL=0V when measuring power save current Fig.4 Circuit for measuring bias current power supply current OUT1 VCC CTL GND OUT2 + 0.33µ 22µ VCC=25V + 22µ A 5V A Fig.5 Circuit for measuring output short-circuit current BA51W12SAT Regulator ICs OUT1 VCC OUT2 CTL GND + 22µ 0.33µ VCC=14V + 2.0V V 22µ V 0.8V Fig.6 Circuit for measuring mode switching voltage OUT1 VCC OUT2 CTL GND + VCC=14V 0.33µ + 22µ A 5V Fig.7 Circuit for measuring input high level current !Application circuit OUTPUT1 + 22µ Vcc OUTPUT2 GND CTL + 0.33µ 5V Fig.8 22µ 22µ BA51W12SAT Regulator ICs !Operation notes (1) Although the circuit examples included in this hand-book are highly recommendable for general use, you should be thoroughly familiar with circuit characteristics as they relate to your own use conditions. If you intend to change the number of external circuits, leave an ample margin, taking into account discrepancies in both static and dynamic characteristics of external parts and Rohm ICs. In addition, please be advised that Rohm cannot provide complete assurance regarding patent rights. (2) Operating power supply voltage When operating within the proper ranges of power supply voltage and ambient temperature, most circuit functions are guaranteed. Although the rated values of electrical characteristics cannot be absolutely guaranteed, characteristic values do not change drastically within the proper rages. (3) Power dissipation (Pd) Refer to the power dissipation characteristics in Fig.12. If power dissipation exceeds the allowable limit, the functionality of the IC will be degraded (such as reduction of current capacity by increased chip temperature). Make sure to use the IC within the allowable range of power dissipation with a sufficient margin. (4) Preventing oscillation at each output and bypass capacitor To stop output oscillation, make sure to connect a capacitor between GND and each output pin (capacitance of at least 10µF over the whole operating temperature range is recommended). Oscillation can occur if capacitance is susceptible to temperature. We recommended using a tantalum capacitor with minimal changes in capacitance. Also, output can be further stabilized by connecting a bypass capacitor of about 0.33µF between the input pin and GND. Place the capacitor as near as possible to the input pin. (5) Overcurrent protection circuit An overcurrent protection circuit is installed in each output system, based on the respective output current. This prevents IC destruction due to overcurrent, by limiting the current with a curve shape of “7” in the voltagecurrent graph. The IC is designed with margins so that current flow will be restricted and latching will be prevented even if a large current suddenly flows through a large capacitor. Note that these protection circuits are only good for preventing damage from sudden accidents. Make sure your design does not cause the protection circuit to operate continuously under transitional conditions (for instance, if output is clamped at 1VF or higher, short mode circuit operates at 1VF or lower). Note that the circuit ability is negatively correlated with temperature. (6) Thermal protection circuit A built-in thermal protection circuit prevents thermal damage to the IC. All outputs are turned off when the circuit operates, and revert to the original state when the temperature drops to a certain level. (7) We recommend installing a bypass line with a diode in your application if there is a mode where potential difference between each output and input (VCC) or GND is reversed from the normal state. A reversed mode may cause damage to the IC. (8) Although the quality of this IC is rigorously controlled, the IC may be destroyed when the applied voltage or the operating temperature exceeds their absolute maximum ratings. Because short mode or open mode cannot be specified when the IC is destroyed, be sure to take physical safety measures, such as fusing, if any of the absolute maximum ratings might be exceeded. BA51W12SAT Regulator ICs (9) Recommended to put diode for protection in case of output pin connected with large load of impedance or reserve current occurred at initial and output off. (Example) Output (10) When used within a strong magnetic field, be aware that there is a slight possibility of malfunction. (11) We are confident in recommending the above application circuit example, but we ask that you carefully check the characteristics of this circuit before using it. If using circuit after modifying other external circuit constants, be careful to ensure adequate margins for variation between external devices and this IC, including not only static characteristics but also transient characteristics. This IC is a bipolar IC which (as shown in Figure 9) has P+ isolation in the P substrate and between the various pins. A P-N junction is formed form this P layer and the N layer of each pin. For example the relation between each potentials is as follows, (When GND > PinB and GND > PinA, the P-N junction operates as a parasitic diode.) (When PinB > GND > PinA, the P-N junction operates as a parasitic transistor.) Parasitic diodes can occur inevitably in the structure of the IC. The operation of parasitic diodes can result in mutual interference among circuits as well as operation faults and physical damage. Accordingly, you must not use methods by which parasitic diodes operate, such as applying a voltage that is lower than the GND (P substrate) voltage to an input pin. Transistor (NPN) Resistance (Pin B) (Pin A) B C E GND N P P + P N N P substrate P + + P N Parasitic diode N N N P substrate Parasitic diode or transistor (Pin B) GND + P GND (Pin A) C Parasitic diode B E GND GND Parasitic diode or transistor Fig.9 Simplified structure of bipolar IC BA51W12SAT Regulator ICs !Electrical characteristic curves 12 10 OUTPUT VOLTAGE : VO (V) OUTPUT VOLTAGE : VO (V) 10 VO1 9 8 7 6 VO2 5 4 3 2 28 Ta=25°C IO=0mA VO1 VO2 9 8 7 Over voltage protection circuit, ON Vcc=28V(Typ.) 6 5 4 3 2 20 16 12 (3) 4 0 0 500 1000 1500 (4) 0 0 2000 (2) 8 1 1 0 (1) With infinte heat sink (2) With Al heat sink 100×100×2 (mm2) (3) With Al heat sink 50×50×2 (mm2) (4) Without heat sink Note : When using AI heat sink, a tightening torque of 6 (kg cm) and silicon grease is applied 24 POWER DISSIPATION : Pd (W) VCC=14V Ta=25˚C 11 6 12 18 24 30 36 42 48 54 60 0 25 50 75 100 125 150 OUTPUT CURRENT : IO (mA) POWER SUPPLY VOLTAGE : VCC (V) AMBIENT TEMPERATURE : Ta (˚C) Fig.10 Output current capacity characteristics (Typ.) Fig.11 Output voltage characteristics (Typ.) Fig.12 Thermal derating characteristics !External dimentions (Units : mm) 7.0 4.5 + 0.3 − 0.1 φ 3.2 ± 0.1 + 0.3 − 0.1 2.8 + 0.2 − 0.1 17.5 25.8 17.0 − 0.2 31.5Max. 8.0 ± 0.2 0.7 10.0 − 0.1 (2.0) 2.8 + 0.2 − 0.1 23.4 + 0.3 − 0.1 + 0.4 φ 3.2 ± 0.1 1.8 ± 0.2 4.5 12.0 ± 0.2 + 0.3 − 0.1 8.0 ± 0.2 + 0.3 − 0.1 7.0 1.2 1.2 ± 0.2 17.0 13.5Min. 12.0 ± 0.2 + 0.4 − 0.2 1.8 ± 0.2 + 0.3 10.0 0.8 1.2 0.8 0.5 ± 0.1 1 2 3 4 5 1.778 1.778 0.5 + 0.1 (2.85) 4.25 8.15 2.85 12345 TO220FP-5 TO220FP-5(V5)