Precision Voltage Regulators

A723

PRECISION VOLTAGE REGULATORS

SLVS057D – AUGUST 1972 – REVISED JULY 1999

POST OFFICE BOX 655303

•

DALLAS, TEXAS 75265

150-mA Load Current Without External

Power Transistor

Adjustable Current-Limiting Capability

Input Voltages up to 40 V

Output Adjustable From 2 V to 37 V

Direct Replacement for Fairchild

A723C

description

The

A723 is a precision integrated-circuit

voltage regulator, featuring high ripple rejection,

excellent input and load regulation, excellent temperature stability, and low standby current. The circuit consists

of a temperature-compensated reference-voltage amplifier, an error amplifier, a 150-mA output transistor, and

an adjustable-output current limiter.

The

A723 is designed for use in positive or negative power supplies as a series, shunt, switching, or floating

regulator. For output currents exceeding 150 mA, additional pass elements can be connected as shown in

Figures 4 and 5.

The

A723C is characterized for operation from 0

C to 70

AVAILABLE OPTIONS

PACKAGED DEVICES

CHIP

PLASTIC

DIP

(N)

SMALL

OUTLINE

(D)

CHIP

FORM

(Y)

C to 70

A723CN

A723CD

A723Y

The D package is available taped and reeled. Add the suffix

R to the device type (e.g.,

A723CDR). Chip forms are

tested at 25

functional block diagram

–

VCC–

CURR LIM CURR SENS

Current

Limiter

Series Pass

Transistor

Regulated

Output

VCC+

Ref

Amp

Current

Source

Temperature-

Compensated

Reference Diode

FREQ COMP

REF

IN–

IN+

Error

Amp

Please be aware that an important notice concerning availability, standard warranty, and use in critical applications of

Texas Instruments semiconductor products and disclaimers thereto appears at the end of this data sheet.

1999, Texas Instruments Incorporated

PRODUCTION DATA information is current as of publication date.

Products conform to specifications per the terms of Texas Instruments

standard warranty. Production processing does not necessarily include

testing of all parameters.

CURR LIM

CURR SENS

IN–

IN+

REF

CC–

FREQ COMP

CC+

OUTPUT

D OR N PACKAGE

(TOP VIEW)

A723

PRECISION VOLTAGE REGULATORS

SLVS057D – AUGUST 1972 – REVISED JULY 1999

POST OFFICE BOX 655303

•

DALLAS, TEXAS 75265

schematic

VCC+

15 k

Ω

OUTPUT

6.2 V

FREQ COMP

CURR SENS

CURR LIM

IN–

IN+

REF

150

Ω

1 k

Ω

20 k

Ω

300

Ω

5 k

Ω

30 k

Ω

100

Ω

1 k

Ω

25 k

Ω

500

Ω

15 k

Ω

5 pF

VCC–

Resistor and capacitor values shown are nominal.

absolute maximum ratings over operating free-air temperature range (unless otherwise noted)

†

Peak voltage from V

CC+

to V

CC–

≤

50 ms)

50 V

. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Continuous voltage from V

CC+

to V

CC–

. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Input-to-output voltage differential

40 V

. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Differential input voltage to error amplifier

5 V

. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Voltage between noninverting input and V

CC–

. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Current from V

25 mA

. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Current from REF

15 mA

. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Package thermal impedance,

(see Notes 1 and 2): D package

C/W

. . . . . . . . . . . . . . . . . . . . . . . . . . . .

N package

101

C/W

. . . . . . . . . . . . . . . . . . . . . . . . . . .

Lead temperature 1,6 mm (1/16 inch) from case for 10 seconds: D or N package

260

. . . . . . . . . . . . . . . .

Storage temperature range, T

stg

–65

C to 150

. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

† Stresses beyond those listed under “absolute maximum ratings” may cause permanent damage to the device. These are stress ratings only, and

functional operation of the device at these or any other conditions beyond those indicated under “recommended operating conditions” is not

implied. Exposure to absolute-maximum-rated conditions for extended periods may affect device reliability.

NOTES:

1. Maximum power dissipation is a function of TJ(max),

JA, and TA. The maximum allowable power dissipation at any allowable

ambient temperature is PD = (TJ(max) – TA)/

JA. Operating at the absolute maximum TJ of 150

C can impact reliability.

2. The package thermal impedance is calculated in accordance with JESD 51, except for through-hole packages, which use a trace

length of zero.

A723

PRECISION VOLTAGE REGULATORS

SLVS057D – AUGUST 1972 – REVISED JULY 1999

POST OFFICE BOX 655303

•

DALLAS, TEXAS 75265

recommended operating conditions

MIN

MAX

UNIT

Input voltage, VI

9.5

Output voltage, VO

Input-to-output voltage differential, VC – VO

Output current, IO

150

Operating free-air temperature range, TA

A723C

electrical characteristics at specified free-air temperature (see Notes 3 and 4)

PARAMETER

TEST CONDITIONS

A723C

UNIT

PARAMETER

TEST CONDITIONS

MIN

TYP

MAX

UNIT

VI = 12 V to VI = 15 V

0.1

Input regulation

VI = 12 V to VI = 40 V

mV/V

VI = 12 V to VI = 15 V

C to 70

Ripple rejection

f = 50 Hz to 10 kHz,

Cref = 0

Ripple rejection

f = 50 Hz to 10 kHz,

Cref = 5

Output regulation

–0.3

–2

mV/V

Output regulation

C to 70

–6

mV/V

Reference voltage, Vref

6.8

7.15

7.5

Standby current

VI = 30 V,

IO = 0

2.3

Temperature coefficient of output voltage

C to 70

0.003

0.015

Short-circuit output current

RSC = 10

Ω

VO = 0

Output noise voltage

BW = 100 Hz to 10 kHz,

Cref = 0

Output noise voltage

BW = 100 Hz to 10 kHz,

Cref = 5

2.5

NOTES:

3. For all values in this table, the device is connected as shown in Figure 1 with the divider resistance as seen by the error amplifier

≤

10 k

Ω

. Unless otherwise specified, VI = VCC+ = VC = 12 V, VCC– = 0, VO = 5 V, IO = 1 mA, RSC = 0, and Cref = 0.

4. Pulse-testing techniques must be used that will maintain the junction temperature as close to the ambient temperature as possible.

electrical characteristics, T

= 25

C (see Notes 3 and 4)

PARAMETER

TEST CONDITIONS

A723Y

UNIT

PARAMETER

TEST CONDITIONS

MIN

TYP

MAX

UNIT

Input regulation

VI = 12 V to VI = 15 V

0.1

mV/V

Input regulation

VI = 12 V to VI = 40 V

mV/V

Ripple rejection

f = 50 Hz to 10 kHz,

Cref = 0

Ripple rejection

f = 50 Hz to 10 kHz,

Cref = 5

Output regulation

–0.3

mV/V

Reference voltage, Vref

7.15

Standby current

VI = 30 V,

IO = 0

2.3

Short-circuit output current

RSC = 10

Ω

VO = 0

Output noise voltage

BW = 100 Hz to 10 kHz,

Cref = 0

Output noise voltage

BW = 100 Hz to 10 kHz,

Cref = 5

2.5

NOTES:

3. For all values in this table, the device is connected as shown in Figure 1 with the divider resistance as seen by the error amplifier

≤

10 k

Ω

. Unless otherwise specified, VI = VCC+ = VC = 12 V, VCC– = 0, VO = 5 V, IO = 1 mA, RSC = 0, and Cref = 0.

4. Pulse-testing techniques must be used that will maintain the junction temperature as close to the ambient temperature as possible.

A723

PRECISION VOLTAGE REGULATORS

SLVS057D – AUGUST 1972 – REVISED JULY 1999

POST OFFICE BOX 655303

•

DALLAS, TEXAS 75265

APPLICATION INFORMATION

Table 1. Resistor Values (k

Ω

) for Standard Output Voltages

OUTPUT

VOLTAGE

APPLICABLE

FIGURES

FIXED OUTPUT

OUTPUT ADJUSTABLE

10%

(SEE NOTE 6)

(V)

(SEE NOTE 5)

Ω

)

Ω

)

Ω

)

Ω

)

Ω

)

3.0

1, 5, 6, 9, 11, 12 (4)

4.12

3.01

1.8

0.5

1.2

3.6

1, 5, 6, 9, 11, 12 (4)

3.57

3.65

1.5

0.5

1.5

5.0

1, 5, 6, 9, 11, 12 (4)

2.15

4.99

0.75

0.5

2.2

6.0

1, 5, 6, 9, 11, 12 (4)

1.15

6.04

0.5

2.7

9.0

2, 4, (5, 6, 9, 12)

1.87

7.15

0.75

1.0

2.7

2, 4, (5, 6, 9, 12)

4.87

7.15

2.0

1.0

3.0

2, 4, (5, 6, 9, 12)

7.87

7.15

3.3

1.0

3.0

2, 4, (5, 6, 9, 12)

21.0

7.15

5.6

1.0

2.0

3.57

48.7

2.2

3.57

78.7

2.2

100

3.57

105

2.2

250

3.57

255

2.2

240

–6

(see Note 7)

3, 10

3.57

2.43

1.2

0.5

0.75

–9

3, 10

3.48

5.36

1.2

0.5

2.0

–12

3, 10

3.57

8.45

1.2

0.5

3.3

–15

3, 10

3.57

11.5

1.2

0.5

4.3

–28

3, 10

3.57

24.3

1.2

0.5

–45

3.57

41.2

2.2

–100

3.57

95.3

2.2

–250

3.57

249

2.2

240

NOTES:

5. The R1/R2 divider can be across either VO or V(ref). If the divider is across

V(ref), use the figure numbers without parentheses. If the divider is across

VO, use the figure numbers in parentheses.

6. To make the voltage adjustable, the R1/R2 divider shown in the figures must

be replaced by the divider shown below.

Adjustable Output Circuit

7. For Figures 3, 8, and 10, the device requires a minimum of 9 V between VCC+

and VCC– when VO is equal to or more positive than –9 V.

A723

PRECISION VOLTAGE REGULATORS

SLVS057D – AUGUST 1972 – REVISED JULY 1999

POST OFFICE BOX 655303

•

DALLAS, TEXAS 75265

APPLICATION INFORMATION

Table 2. Formulas for Intermediate Output Voltages

OUTPUTS FROM 2 V TO 7 V

SEE FIGURES 1, 5, 6, 9, 11, 12 (4)

AND NOTE 5

OUTPUTS FROM 4 V TO 250 V

SEE FIGURE 7 AND NOTE 5

CURRENT LIMITING

(ref)

)

(ref)

R2 – R1

(limit)

[

0.65 V

OUTPUTS FROM 7 V TO 37 V

SEE FIGURES 2, 4, (5, 6, 9, 11, 12)

AND NOTE 5

OUTPUTS FROM –6 V TO –250 V

SEE FIGURES 3, 8, 10

AND NOTES 5 AND 7

FOLDBACK CURRENT LIMITING

SEE FIGURE 6

(ref)

)

–

(ref)

)

(knee)

[

)

(R3

)

R4) 0.65 V

[

0.65 V

)

NOTES:

5. The R1/R2 divider can be across either VO or V(ref). If the divider is across V(ref), use figure numbers without parentheses. If the

divider is across VO, use the figure numbers in parentheses.

7. For Figures 3, 8, and 10, the device requires a minimum of 9 V between VCC+ and VCC– when VO is equal to or more positive than

–9 V.

REF

VCC+

OUTPUT

CURR LIM

CURR SENS

IN+

VCC– FREQ COMP

IN–

RSC

C(ref)

100 pF

Regulated

Output, VO

R3 (see Notes A and B)

A723

NOTES: A.

B. R3 can be eliminated for minimum component count. Use direct connection (i.e., R3 = 0).

)

for a minimum

Figure 1. Basic Low-Voltage Regulator (V

= 2 V to 7 V)

A723

PRECISION VOLTAGE REGULATORS

SLVS057D – AUGUST 1972 – REVISED JULY 1999

POST OFFICE BOX 655303

•

DALLAS, TEXAS 75265

APPLICATION INFORMATION

100 pF

Regulated Output,

RSC

REF

VCC+

OUTPUT

CURR LIM

CURR SENS

IN+

VCC– FREQ COMP

IN–

(see Notes A and B)

A723

NOTES: A.

B. R3 can be eliminated for minimum component count. Use direct connection (i.e., R3 = 0).

)

for a minimum

Figure 2. Basic High-Voltage Regulator (V

= 7 V to 37 V)

100 pF

2N5001

2 k

Ω

R3 =

3 k

Ω

R4 = 3 k

Ω

REF

VCC+

OUTPUT

CURR LIM

CURR SENS

IN+

VCC– FREQ COMP

IN–

A723

Regulated Output,

Figure 3. Negative-Voltage Regulator

A723

PRECISION VOLTAGE REGULATORS

SLVS057D – AUGUST 1972 – REVISED JULY 1999

POST OFFICE BOX 655303

•

DALLAS, TEXAS 75265

APPLICATION INFORMATION

500 pF

RSC

2N3997

REF

VCC+

OUTPUT

CURR LIM

CURR SENS

IN+

VCC– FREQ COMP

IN–

A723

Regulated Output,

Figure 4. Positive-Voltage Regulator (External npn Pass Transistor)

RSC

2N5001

Ω

REF

VCC+

OUTPUT

CURR LIM

CURR SENS

IN+

VCC– FREQ COMP

IN–

A723

1000 pF

Regulated Output,

Figure 5. Positive-Voltage Regulator (External pnp Pass Transistor)

A723

PRECISION VOLTAGE REGULATORS

SLVS057D – AUGUST 1972 – REVISED JULY 1999

POST OFFICE BOX 655303

•

DALLAS, TEXAS 75265

APPLICATION INFORMATION

1000 pF

RSC

IOS

lknee

REF

VCC+

OUTPUT

CURR LIM

CURR SENS

IN+

VCC– FREQ COMP

IN–

A723

Regulated Output,

Figure 6. Foldback Current Limiting

2N2580

RSC = 1

Ω

2 k

Ω

500 pF

1N1826

REF

VCC+

OUTPUT

CURR LIM

CURR SENS

IN+

VCC– FREQ COMP

IN–

A723

R4 =

3 k

Ω

R3 =

3 k

Ω

Regulated Output,

Figure 7. Positive Floating Regulator

A723

PRECISION VOLTAGE REGULATORS

SLVS057D – AUGUST 1972 – REVISED JULY 1999

POST OFFICE BOX 655303

•

DALLAS, TEXAS 75265

APPLICATION INFORMATION

2N5287

10 k

Ω

1N759

500 pF

10 k

Ω

REF

VCC+

OUTPUT

CURR LIM

CURR SENS

IN+

VCC– FREQ COMP

IN–

A723

Regulated Output,

R3 =

3 k

Ω

R4 =

3 k

Ω

Figure 8. Negative Floating Regulator

0.1

1 k

Ω

1 M

Ω

1N4005

L = 1.2 mH

(see Note A)

2N5005

2N5153

3 k

Ω

REF

VCC+

OUTPUT

CURR LIM

CURR SENS

IN+

VCC– FREQ COMP

IN–

A723

NOTE A: L is 40 turns of No. 20 enameled copper wire wound on Ferroxcube P36/22-3B7 potted core, or equivalent, with a 0.009-inch air gap.

Regulated Output,

Figure 9. Positive Switching Regulator