Datasheet BA44W12SAT Datasheet (ROHM)

BA44W12SAT

Regulator ICs

Dual output voltage regulator with power saving

BA44W12SAT

The BA44W12SAT is a general-purpose power supply with outputs : 8V, 1A and 8V, 500mA. The IC is available in a compact TO220FP-5 package. The outputs can be turned off during the power saving state with a built-in switch. Also built in the IC are an overcurrent protection circuit, an overvoltage protection circuit, and a thermal shutdown circuit.

!!!!

Applications

Car audio systems, VCRs, facsimiles, air conditions, 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

Parameter Symbol Limits Unit Power supply voltage V Power dissipation Pd Operating temperature Topr −40~+85 ˚C Storage temperature Tstg −55~+150 ˚C Peak applied voltage V

∗1 Reduced by 16mW for each increase in Ta of 1˚C over 25˚C.

2 Applied time is less than 200ms (tr≥1ms).

∗

tr≥1ms

50V

35V

0V

(Ta=25°C)

CC

Peak 50

Max.200ms

35 V

1

∗

2000

2

∗

!!!!Recommended operating conditions (Ta=25°C)

Parameter

Power supply voltage V

Symbol Min. Typ. Max. Unit

CC

9.0 25 V13

mW

V

Regulator ICs

!!!!Block diagram

V

CC

2

CTL

5

REFERENCE VOLTAGE

BA44W12SAT

8V

1

OUT1

+

GND

3

!Pin descriptions

Pin No.

1 2 3 4 5

Pin name

OUT1

GND

OUT2

V

CC

CTL

Output 1 (8V, 1A) Power supply Ground Output 2 (8V, 500mA) ON / OFF switch

Function

8V

4

OUT2

+

Regulator ICs

!!!!Input / output circuits

CTL (5pin)

OUT1, 2

CC

(2pin)

V

BA44W12SAT

!!!!

Electrical characteristics

Parameter Power save supply current Bias current

25k

GND (3pin)

10.8k (1pin)

10.8k (4pin)

(unless otherwise noted, Ta=25°C, VCC=13.0V)

0

Max. Unit

10 µA

5.0 mA

Symbol

I

ST

I

b

Min.

-

Typ.

3.0

2k

GND (3pin)

OFF mode ON mode

1, 4pin

Conditions Test circuit

<8V output section> (Output 1) Output voltage 1 Minimum I / O voltage differential 1 Output current capacity 1

Ripple rejection ratio 1 Input stabillty 1

Load regulation 1

Reg.I1

Reg.L1

Output short-circuit current 1

V

O1

∆V

I

O1

R.R1

I

OS1

-

8.4 V

0.5 V

-A

-dB

100 mV 150 mV

-mA

7.6

O1

8.0

0.3

-

1.0

-

55

50 100 150

I

O1

=500mA

I

O1

=500mA VCC=7.6V

I

O1

=500mA, f=120Hz

IN

=1V

rms

e VCC=9→25V, IO=500mA I

O

=5mA→1A

CC

=25V

V <8V output section> (Output 2) Output voltage 2 Minimum I / O voltage differential

2

Output current capacity 2 Ripple rejection ratio 2 Input stabillty 2

Load regulation 2 Output short-circuit current 2

V

O2

∆V

O2

I

O2

R.R2

Reg.I2

Reg.L2

I

OS2

7.6

500

-

8.4 V

0.5 V

-mA

-dB

100 mV 100 mV

-mA

8.0

0.3

-

60 50

50

100

O2

=350mA

I

O2

=350mA VCC=7.6V

I

O2

=350mA, f=120Hz

IN

=1V

rms

e

VCC=9→25V, IO=350mA

I

O

=5mA→500mA

V

CC

=25V <CTL section> ON mode voltage OFF mode voltage Input high level current

Note) All the characteristic values are measured with a 0.33µF-capacitor connected the input pin and 22µF-capacitor connected to the output pin. Measurements are made by using a plus (tw≤10ms, duty cycle≤5%) in all cases but noise voltage and the ripple rejection ratio.

V

th

V

th

I

IN

2.0

1

2

-

150

-V

0.8 V

- µA

Output ACTIVE MODE Output OFF MODE

th

=5V

V

Fig.4 Fig.4

Fig.1 Fig.3 Fig.1

Fig.2 Fig.1

Fig.1 Fig.5

Fig.1 Fig.3 Fig.1

Fig.2 Fig.1

Fig.1 Fig.5

Fig.6 Fig.6 Fig.7

Regulator ICs

!!!!Measurement circuits

CC

V

0.33µ

V

CC

CTL GND

5V

OUT1

OUT2

BA44W12SAT

+

22µ

V

+

22µ

V

I

O2

I

O1

V

CC

10Ω5W

VCC=13V, IO=500mA VCC=13V, IO=350mA VCC=9→25V, IO=500mA VCC=9→25V, IO=350mA VCC=13V, IO=5mA→1A VCC=13V, IO=5mA→500mA VCC=13V VCC=13V

when measuring output voltage 1 when measuring output voltage 2 when measuring input stability 1 when measuring input stability 2 when measuring load reguration 1 when measuring load reguration 2 when measuring output current capacity 1 when measuring output current capacity 2

Fig.1 Circuit for measuring output voltage, input stability, load regulation, and output current capacity

OUT1

OUT2

+

22

µ

13V,

IO1=

500mA when meauring the ripple rejection ratio 1

13V,

IO2=

350mA when meauring the ripple rejection ratio 2

350mA

+

22

µ

+

100µ

e

IN

f=120Hz

0.33µ

=1V

rms

V

CC

CTL GND

VCC= VCC=

5V

500mA

Fig.2 Circuit for measuring ripple rejection ratio

Regulator ICs

BA44W12SAT

V

CC

V

OUT2

GNDCTL

0.33µ

V

CC

5V

+

22µ

+

V

500mA

V

350mA

VCC=7.6V when measuring minimum I / O voltage difference 1 VCC=7.6V when measuring minimum I / O voltage difference 2

Fig.3 Circuit for measuring minimum I / O voltage difference

OUT1

CC

A

V

0.33µ

V

CC

OUT1

OUT2

GNDCTL

+

22µ

+

22µ

5V

VCC=

13V, I

O

=

0mA, V

CTL

=5V when measuring bias current

VCC=

13V, I

O

=

0mA, V

CTL

=0V when measuring power save supply current

Fig.4 Circuit for measuring bias current and power save supply current

OUT1

CC

V

OUT2

GNDCTL

+

V

CC

=25V

0.33µ

+

5V

22µ

A

Fig.5 Circuit for measuring output short-circuit current

Regulator ICs

BA44W12SAT

VCC=13V

V

OUT1

OUT2

GNDCTL

+

22µ

V

+

22µ

V

0.33µ

CC

V

2.0V 0.8V

Fig.6 Circuit for measuring mode switching voltage

V

CC

=13V

0.33µ

A

OUT1

OUT2

GNDCTL

+

22µ

+

22µ

!!!!Application circuit

0.33µ

5V

Fig.7 Circuit for measuring input high level current

OUTPUT1

Vcc

OUTPUT2

CTL

GND

5V

+

22µ

+

22µ

Fig.8

BA44W12SAT

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 fuctionality 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 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 V

and GND.

CC

(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 voltage current 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 current suddenly flows through a large capacitor. Note that theses protection circuits are only good for preventing damage from sudden accidents. Make sure your design does not case the protection circuit to operate continuously under transitional conditions (for instance, if output is clamped at 1V higher, short mode circuit operates at 1V

or lower). Note that the capacitance is negatively correlated with

F

or

F

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 in your application if there is a mode where potential difference between each output and input (V

) or GND is reversed from the normal state. A reversed mode may cause damage to the IC.

CC

(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.

BA44W12SAT

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.

(Pin A)

N

+

P

Resistance

N

P substrate

(Pin A)

GND

(Pin B)

P

Parasitic diode

GND

Parasitic diode

+

P

N

Fig.9 Simplified structure of bipolar IC

N

Parasitic diode or transistor

P

+

(Pin B)

C

Transistor (NPN)

B

E

N

P

N

P substrate

GND

C

B

E

GND

+

P

N

Parasitic diode or transistor

GND

Regulator ICs

!!!!Electrical characteristic curves

12 11 10

V)

(

9

O

8 7 6

V

5 4 3

OUTPUT VOLTAGE : V

2 1

0

0 500 1000 1500 2000

OUTPUT CURRENT : I

Fig.10 Output current capacity characteristics (Typ.)

!!!!External dimentions (Units : mm)

VCC=13V Ta=25˚C

O2

V

O1

O

(

mA)

9 8

V)

7

(

O

6 5 4 3 2

OUTPUT VOLTAGE : V

1 0

Ta=25˚C IO=0mA

Over voltage protection circuit, ON V

CC

0 6 12 2418 3630 42 5448

POWER SUPPLY VOLTAGE : V

Fig.11 Output voltage characteristics (Typ.)

V

O1

V

O2

=28V(Typ.)

CC

(

V)

BA44W12SAT

28

24

20

16

12

8

POWER DISSIPATION : Pd (W)

4

0

0 25 50 10075 125 150

AMBIENT TEMPERATURE : Ta (˚C)

Fig.12 Thermal derating characteristics

(1) With infinte heat sink (2) With Al heat sink 100×100×2 (mm (3) With Al heat sink

(1)

50×50×2 (mm (4) Without heat sink

Note : When using AI heat sink, a tightening torque of 6 (kg cm) and silicon grease is applied

(2)

(3) (4)

2

)

2

)

3.2 ± 0.1

φ

0.5 + 0.1

+ 0.3

4.5

− 0.1 + 0.2

2.8

− 0.1

2.85

+ 0.4

31.5Max.

10.0

7.0

1.8 ± 0.2

− 0.2

17.0

12.0 ± 0.2

8.0 ± 0.2

12345

+ 0.4

− 0.2

17.0

13.5Min.

12.0 ± 0.2

1.8 ± 0.2

0.7

8.0 ± 0.2

1.2 ± 0.2

+ 0.3

10.0

− 0.1 + 0.3

7.0

− 0.1

1.2

0.8

23451

1.778

TO220FP-5 TO220FP-5 (V5)

+ 0.3

− 0.1 + 0.3

− 0.1

1.2

0.8

1.778

3.2 ± 0.1

φ

0.5 ± 0.1

+ 0.3

4.5

− 0.1 + 0.2

2.8

− 0.1

17.5

(2.0)

23.4

25.8

(2.85)

4.25

8.15