µA723
PRECISION VOLTAGE REGULATORS
SLVS057D – AUGUST 1972 – REVISED JULY 1999
1
POST OFFICE BOX 655303 • DALLAS, TEXAS 75265
D
150-mA Load Current Without External
Power Transistor
D
Adjustable Current-Limiting Capability
D
Input Voltages up to 40 V
D
Output Adjustable From 2 V to 37 V
D
Direct Replacement for Fairchild µA723C
description
The µA723 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 µA723 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 µA723C is characterized for operation from 0°C to 70°C.
AVAILABLE OPTIONS
PACKAGED DEVICES
CHIP
TAPLASTIC
DIP
(N)
SMALL
OUTLINE
(D)
CHIP
FORM
(Y)
0°C to 70°CµA723CN µA723CD µA723Y
The D package is available taped and reeled. Add the suffix
R to the device type (e.g., µA723CDR). Chip forms are
tested at 25°C.
functional block diagram
–
+
VCC– CURR LIM CURR SENS VZ
Current
Limiter
VC
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.
Copyright 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.
1
2
3
4
5
6
7
14
13
12
11
10
9
8
NC
CURR LIM
CURR SENS
IN–
IN+
REF
VCC–
NC
FREQ COMP
VCC+
VC
OUTPUT
VZ
NC
D OR N PACKAGE
(TOP VIEW)
µA723
PRECISION VOLTAGE REGULATORS
SLVS057D – AUGUST 1972 – REVISED JULY 1999
2POST OFFICE BOX 655303 • DALLAS, TEXAS 75265
schematic
VCC+ VC
15 kΩOUTPUT
6.2 V
VZ
FREQ COMP
CURR SENS
CURR LIM
IN–IN+REF
150 Ω
1 kΩ
20 kΩ
300 Ω
5 kΩ
30 kΩ
100 Ω
1 kΩ
25 kΩ
500 Ω
15 kΩ
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 VCC+ to VCC– (tw ≤50 ms) 50 V. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Continuous voltage from VCC+ to VCC– 40 V. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Input-to-output voltage differential 40 V. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Differential input voltage to error amplifier ±5 V. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Voltage between noninverting input and VCC– 8 V. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Current from VZ 25 mA. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Current from REF 15 mA. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Package thermal impedance, θJA (see Notes 1 and 2): D package 86°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°C. . . . . . . . . . . . . . . .
Storage temperature range, Tstg –65°C to 150°C. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
†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 af fect device reliability.
NOTES: 1. Maximum power dissipation is a function of TJ(max), θJA, and TA. The maximum allowable power dissipation at any allowable
ambient temperature is PD = (TJ(max) – TA)/θJA. 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.
µA723
PRECISION VOLTAGE REGULATORS
SLVS057D – AUGUST 1972 – REVISED JULY 1999
3
POST OFFICE BOX 655303 • DALLAS, TEXAS 75265
recommended operating conditions
MIN MAX UNIT
Input voltage, VI9.5 40 V
Output voltage, VO2 37 V
Input-to-output voltage differential, VC – VO3 38 V
Output current, IO150 mA
Operating free-air temperature range, TAµA723C 0 70 °C
electrical characteristics at specified free-air temperature (see Notes 3 and 4)
PARAMETER
TEST CONDITIONS
T
µA723C
UNIT
PARAMETER
TEST
CONDITIONS
T
AMIN TYP MAX
UNIT
VI = 12 V to VI = 15 V 25°C 0.1 1
Input regulation VI = 12 V to VI = 40 V 25°C 1 5 mV/V
VI = 12 V to VI = 15 V 0°C to 70°C 3
Ri
pp
le rejection
f = 50 Hz to 10 kHz, Cref = 0 25°C 74
dB
Ripple
rejection
f = 50 Hz to 10 kHz, Cref = 5 µF 25°C 86
dB
Out
p
ut regulation
25°C –0.3 –2
mV/V
O
u
tp
u
t
reg
u
lation
0°C to 70°C –6
mV/V
Reference voltage, V ref 25°C 6.8 7.15 7.5 V
Standby current VI = 30 V, IO = 0 25°C 2.3 4 mA
Temperature coef ficient of output voltage 0°C to 70°C 0.003 0.015 %/°C
Short-circuit output current RSC = 10 Ω, VO = 0 25°C 65 mA
Out
p
ut noise voltage
BW = 100 Hz to 10 kHz, Cref = 0 25°C 20
µV
O
u
tp
u
t
noise
v
oltage
BW = 100 Hz to 10 kHz, Cref = 5 µF 25°C 2.5 µ
V
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 kΩ. 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, TA = 25°C (see Notes 3 and 4)
PARAMETER
TEST CONDITIONS
µA723Y
UNIT
PARAMETER
TEST
CONDITIONS
MIN TYP MAX
UNIT
In
p
ut regulation
VI = 12 V to VI = 15 V 0.1
mV/V
Inp
u
t
reg
u
lation
VI = 12 V to VI = 40 V 1
mV/V
Ri
pp
le rejection
f = 50 Hz to 10 kHz, Cref = 0 74
dB
Ripple
rejection
f = 50 Hz to 10 kHz, Cref = 5 µF 86
dB
Output regulation –0.3 mV/V
Reference voltage, V ref 7.15 V
Standby current VI = 30 V, IO = 0 2.3 mA
Short-circuit output current RSC = 10 Ω, VO = 0 65 mA
Out
p
ut noise voltage
BW = 100 Hz to 10 kHz, Cref = 0 20
µV
O
u
tp
u
t
noise
v
oltage
BW = 100 Hz to 10 kHz, Cref = 5 µF 2.5 µ
V
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 kΩ. 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.
µA723
PRECISION VOLTAGE REGULATORS
SLVS057D – AUGUST 1972 – REVISED JULY 1999
4POST OFFICE BOX 655303 • DALLAS, TEXAS 75265
APPLICATION INFORMATION
Table 1. Resistor Values (kΩ) for Standard Output Voltages
OUTPUT
VOLTAGE APPLICABLE
FIGURES
FIXED OUTPUT
±5%
OUTPUT ADJUSTABLE
±10%
(SEE NOTE 6)
(V) (SEE NOTE 5) R1
(kΩ)R2
(kΩ)R1
(kΩ)P1
(kΩ ) P2
(kΩ )
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 0.5 2.7
9.0 2, 4, (5, 6, 9, 12) 1.87 7.15 0.75 1.0 2.7
12 2, 4, (5, 6, 9, 12) 4.87 7.15 2.0 1.0 3.0
15 2, 4, (5, 6, 9, 12) 7.87 7.15 3.3 1.0 3.0
28 2, 4, (5, 6, 9, 12) 21.0 7.15 5.6 1.0 2.0
45 7 3.57 48.7 2.2 10 39
75 7 3.57 78.7 2.2 10 68
100 7 3.57 105 2.2 10 91
250 7 3.57 255 2.2 10 240
–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 10
–45 8 3.57 41.2 2.2 10 33
–100 8 3.57 95.3 2.2 10 91
–250 8 3.57 249 2.2 10 240
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. T o make the voltage adjustable, the R1/R2 divider shown in the figures must
be replaced by the divider shown below.
R1
P1
R2
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.
µA723
PRECISION VOLTAGE REGULATORS
SLVS057D – AUGUST 1972 – REVISED JULY 1999
5
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
VO
+
V(ref)
R2
R1
)
R2 VO
+
V(ref)
2
R2–R1
R1
R3
+
R4 I(limit)
[
0.65 V
RSC
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
VO
+
V(ref)
R1
)
R2
R2 VO
+
–V(ref)
2
R1
)
R2
R1
R3
+
R4
I(knee)
[
VOR3
)
(R3
)
R4) 0.65 V
RSCR4
IOS
[
0.65 V
RSC
R3
)
R4
R4
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
VI
VCC+ VC
OUTPUT
VZ
CURR LIM
CURR SENS
IN+
VCC– FREQ COMP
IN–
RSC
R1
C(ref)
R2 100 pF
Regulated
Output, VO
R3 (see Notes A and B)
µA723
NOTES: A.
B. R3 can be eliminated for minimum component count. Use direct connection (i.e., R3 = 0).
R3
+
R1
R2
R1
)
R2 for a minimum
a
VO
Figure 1. Basic Low-Voltage Regulator (VO = 2 V to 7 V)
µA723
PRECISION VOLTAGE REGULATORS
SLVS057D – AUGUST 1972 – REVISED JULY 1999
6POST OFFICE BOX 655303 • DALLAS, TEXAS 75265
APPLICATION INFORMATION
100 pF R2
R1
Regulated Output,
VO
RSC
VI
REF
VCC+ VC
OUTPUT
VZ
CURR LIM
CURR SENS
IN+
VCC– FREQ COMP
IN–
R3
(see Notes A and B)
µA723
NOTES: A.
B. R3 can be eliminated for minimum component count. Use direct connection (i.e., R3 = 0).
R3
+
R1
R2
R1
)
R2 for a minimum
a
VO
Figure 2. Basic High-Voltage Regulator (VO = 7 V to 37 V)
R2
VI
100 pF
2N5001
2 kΩ
R3 =
3 kΩ
R4 = 3 kΩ
R1
REF
VCC+ VC
OUTPUT
VZ
CURR LIM
CURR SENS
IN+
VCC– FREQ COMP
IN–
µA723
Regulated Output,
VO
Figure 3. Negative-Voltage Regulator
µA723
PRECISION VOLTAGE REGULATORS
SLVS057D – AUGUST 1972 – REVISED JULY 1999
7
POST OFFICE BOX 655303 • DALLAS, TEXAS 75265
APPLICATION INFORMATION
VI
500 pF
R2
R1
RSC
2N3997
REF
VCC+ VC
OUTPUT
VZ
CURR LIM
CURR SENS
IN+
VCC– FREQ COMP
IN–
µA723
Regulated Output,
VO
Figure 4. Positive-Voltage Regulator (External npn Pass Transistor)
RSC
R1
R2
2N5001
VI
60 Ω
REF
VCC+ VC
OUTPUT
VZ
CURR LIM
CURR SENS
IN+
VCC– FREQ COMP
IN–
µA723
1000 pF
Regulated Output,
VO
Figure 5. Positive-Voltage Regulator (External pnp Pass Transistor)
µA723
PRECISION VOLTAGE REGULATORS
SLVS057D – AUGUST 1972 – REVISED JULY 1999
8POST OFFICE BOX 655303 • DALLAS, TEXAS 75265
APPLICATION INFORMATION
1000 pF
R2
R1
VI
RSC
R3
R4 VOIOS
lknee
IO
REF
VCC+ VC
OUTPUT
VZ
CURR LIM
CURR SENS
IN+
VCC– FREQ COMP
IN–
µA723
Regulated Output,
VO
Figure 6. Foldback Current Limiting
R1
R2
2N2580
VI
RSC = 1 Ω
2 kΩ
500 pF
1N1826
REF
VCC+ VC
OUTPUT
VZ
CURR LIM
CURR SENS
IN+
VCC– FREQ COMP
IN–
µA723
R4 =
3 kΩ
R3 =
3 kΩ
Regulated Output,
VO
Figure 7. Positive Floating Regulator
µA723
PRECISION VOLTAGE REGULATORS
SLVS057D – AUGUST 1972 – REVISED JULY 1999
9
POST OFFICE BOX 655303 • DALLAS, TEXAS 75265
APPLICATION INFORMATION
2N5287
10 kΩ
1N759
R2
R1
500 pF
10 kΩ
VI
REF
VCC+ VC
OUTPUT
VZ
CURR LIM
CURR SENS
IN+
VCC– FREQ COMP
IN–
µA723
Regulated Output,
VO
R3 =
3 kΩ
R4 =
3 kΩ
Figure 8. Negative Floating Regulator
0.1 µF
R1
R2
1 kΩ
1 MΩ1N4005
L = 1.2 mH
(see Note A)
2N5005
2N5153
3 kΩ
VI
51 Ω
REF
VCC+ VC
OUTPUT
VZ
CURR LIM
CURR SENS
IN+
VCC– FREQ COMP
IN–
µA723
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,
VO
Figure 9. Positive Switching Regulator
µA723
PRECISION VOLTAGE REGULATORS
SLVS057D – AUGUST 1972 – REVISED JULY 1999
10 POST OFFICE BOX 655303 • DALLAS, TEXAS 75265
APPLICATION INFORMATION
R2
VI
15 pF
2N5004
1 kΩ
(see Note A)
R1
2N3997
1N4005
1 MΩ
100 µF
1 kΩ
220 Ω
0.1 µF
L = 1.2 mH
(see Note B)
REF
VCC+ VC
OUTPUT
VZ
CURR LIM
CURR SENS
IN+
VCC– FREQ COMP
IN–
µA723
NOTES: A. The device requires a minimum of 9 V between VCC+ and VCC– when VO is equal to or more positive than –9 V.
B. 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,
VO
R3 =
3 kΩ
R4 =
3 kΩ
Figure 10. Negative Switching Regulator
1000 pF
VI
2 kΩ
Input From
Series 54/74 Logic
2 kΩ
2N4422
R1
R2
REF
VCC+ VC
OUTPUT
VZ
CURR LIM
CURR SENS
IN+
VCC– FREQ COMP
IN–
RSC
µA723
NOTE A: A current-limiting transistor can be used for shutdown if current limiting is not required.
Regulated Output,
VO
Figure 11. Remote Shutdown Regulator With Current Limiting
µA723
PRECISION VOLTAGE REGULATORS
SLVS057D – AUGUST 1972 – REVISED JULY 1999
11
POST OFFICE BOX 655303 • DALLAS, TEXAS 75265
APPLICATION INFORMATION
VI
1 kΩ
R1
2N3997
5000 pF
100 Ω
R2
REF
VCC+ VC
OUTPUT
VZ
CURR LIM
CURR SENS
IN+
VCC– FREQ COMP
IN–
µA723
Regulated Output,
VO
Figure 12. Shunt Regulator
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accordance with TI’s standard warranty. Testing and other quality control techniques are utilized to the extent
TI deems necessary to support this warranty . Specific testing of all parameters of each device is not necessarily
performed, except those mandated by government requirements.
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Copyright 1999, Texas Instruments Incorporated
