ETC AN79N05

Voltage Regulators
AN79Nxx Series
3-pin negative output voltage regulator (300 mA type)
■ Overview
AN79Nxx series
The AN79Nxx series is a 3-pin, fixed negative output
type monolithic voltage regulator. Stabilized fixed output
voltage is obtained from unstable DC input voltage without using any external component IC. 12 types of output
voltage are available: −4V, −5V, −6V, −7V, −8V, −9V, −
10V, −12V, −15V, −18V, −20V and −24V. They can be
used widely in power circuits with current capacity of up
to 300mA.
Unit : mm
3.8
0.75±0.25
0.5±0.25 1.44
2.3
4.6
1
2
3
0.5±0.1
1.76
3.5 max.
• No external components
• Output voltage: −4V, −5V, −6V, −7V, −8V, −9V,−10V,
−12V, −15V, −18V, −20V, −24V
• Built-in overcurrent limit circuit
• Built-in thermal overload protection circuit
• Built-in ASO (area of safe operation) protection circuit
15.0 min.
1.94
■ Features
10.8±0.3
8.0 +0.5
–0.1
3.05
1 : Common
2 : Input
3 : Output
SSIP003-P-0000E
■ Block Diagram
1
R1
+
Voltage
Reference
Common
Error Amp.
−
R2
3
Output
Q1
Starter
Thermal
Protection
Pass Tr
Current
Limiter
RSC
2
Input
1
AN79Nxx Series
Voltage Regulators
■ Absolute Maximum Ratings at Ta = 25°C
Parameter
Symbol
Input voltage
VI
Power dissipation
PD
Operating ambient temperature
Storage temperature
Rating
−35 *1
Unit
V
−40 *2
8 *3
W
Topr
−20 to +80
°C
Tstg
−55 to +150
°C
V
*1 AN79N04, AN79N05, AN79N06, AN79N07, AN79N08, AN79N09, AN79N10, AN79N12, AN79N15, AN79N18
*2 AN79N20, AN79N24
*3 Follow the derating curve. When Tj exceeds 150°C, the internal circuit cuts off the output.
■ Electrical Characteristics at Ta = 25°C
• AN79N04 (−4V type)
Parameter
Symbol
Conditions
Output voltage
VO
Tj = 25°C
Output voltage tolerance
VO
VI = −6 to −25V, IO = 5 to 200mA
Line regulation
Load regulation
Bias current
REGIN
REGL
IBias
V
−4.2
V
mV
VI = −7 to −17V, Tj = 25°C
4
20
mV
IO = 1 to 300mA, Tj = 25°C
20
80
mV
IO = 5 to 200mA, Tj = 25°C
10
40
mV
3
5
mA
0.5
mA
0.1
mA
Tj = 25°C
Bias current fluctuation to load
∆IBias(L)
IO = 5 to 200mA, Tj = 25°C
RR
−4.16
Unit
40
VI = −7 to −25V, Tj = 25°C
Ripple rejection ratio
−4
−3.8
Max
9
∆IBias(IN)
Vno
−3.84
Typ
VI = −6 to −25V, Tj = 25°C
Bias current fluctuation to input
Output noise voltage
Min
f = 10Hz to 100kHz
VI = −7 to −17V, IO = 50mA,
f = 120Hz
100
µV
dB
60
Minimum input/output voltage difference
VDIF(min)
IO = 200mA, Tj = 25°C
1.1
V
Output short-circuit current
IO(Short)
VI = −35V, Tj = 25°C
10
mA
Peak output current
IO(Peak)
Tj = 25°C
500
mA
Output voltage temperature coefficient
∆VO/Ta
IO = 5mA
− 0.4
mV/°C
Note 1) The specified condition Tj = 25°C means that the test should be carried out within so short a test time (within 10ms) that the
characteristic value drift due to the chip junction temperature rise can be ignored.
Note 2) Unless otherwise specified, VI = −9V, IO = 100mA, CI = 2µF, CO = 1µF and Tj = 0 to 125°C
2
Voltage Regulators
AN79Nxx Series
■ Electrical Characteristics at Ta = 25°C (continued)
• AN79N05 (−5V type)
Parameter
Symbol
Conditions
Min
−4.75
Output voltage
VO
Tj = 25°C
Output voltage tolerance
VO
VI = −7 to −25V, IO = 5 to 200mA
Line regulation
Load regulation
Bias current
REGIN
REGL
IBias
−4.8
VI = −7 to −25V, Tj = 25°C
Typ
−5
10
Max
−5.2
Unit
V
−5.25
V
50
mV
VI = −8 to −18V, Tj = 25°C
5
30
mV
IO = 1 to 300mA, Tj = 25°C
20
100
mV
IO = 5 to 200mA, Tj = 25°C
10
50
mV
3
5
mA
Tj = 25°C
Bias current fluctuation to input
∆IBias(IN)
VI = −8 to −25V, Tj = 25°C
0.5
mA
Bias current fluctuation to load
∆IBias(L)
IO = 5 to 200mA, Tj = 25°C
0.1
mA
Output noise voltage
Vno
Ripple rejection ratio
RR
f = 10Hz to 100kHz
VI = −8 to −18V, IO = 50mA,
f = 120Hz
µV
125
dB
60
Minimum input/output voltage difference
VDIF(min)
IO = 200mA, Tj = 25°C
1.1
V
Output short-circuit current
IO(Short)
VI = −35V, Tj = 25°C
10
mA
Peak output current
IO(Peak)
Tj = 25°C
500
mA
Output voltage temperature coefficient
∆VO/Ta
IO = 5mA
− 0.4
mV/°C
Note 1) The specified condition Tj = 25°C means that the test should be carried out within so short a test time (within 10ms) that the
characteristic value drift due to the chip junction temperature rise can be ignored.
Note 2) Unless otherwise specified, VI = −10V, IO = 100mA, CI = 2µF, CO = 1µF and Tj = 0 to 125°C
• AN79N06 (−6V type)
Parameter
Symbol
Conditions
Output voltage
VO
Tj = 25°C
Output voltage tolerance
VO
VI = −8 to −25V, IO = 5 to 200mA
Line regulation
REGIN
Load regulation
REGL
Bias current
IBias
Bias current fluctuation to input
∆IBias(IN)
Bias current fluctuation to load
∆IBias(L)
Output noise voltage
Vno
Ripple rejection ratio
RR
Min
−5.75
Typ
−6
−5.7
Max
−6.25
Unit
V
−6.3
V
VI = −8 to −25V, Tj = 25°C
11
60
mV
VI = −9 to −19V, Tj = 25°C
6
40
mV
IO = 1 to 300mA, Tj = 25°C
20
120
mV
IO = 5 to 200mA, Tj = 25°C
10
60
mV
3
5
mA
0.5
mA
0.1
mA
Tj = 25°C
VI = −9 to −25V, Tj = 25°C
IO = 5 to 200mA, Tj = 25°C
f = 10Hz to 100kHz
VI = −9 to −19V, IO = 50mA,
f = 120Hz
150
µV
dB
60
Minimum input/output voltage difference
VDIF(min)
IO = 5mA, Tj = 0 to 125°C
1.1
V
Output short-circuit current
IO(Short)
VI = −35V, Tj = 25°C
10
mA
Peak output current
IO(Peak)
Tj = 25°C
Output voltage temperature coefficient
∆VO/Ta
IO = 200mA
500
mA
− 0.4
mV/°C
Note 1) The specified condition Tj = 25°C means that the test should be carried out within so short a test time (within 10ms) that the
characteristic value drift due to the chip junction temperature rise can be ignored.
Note 2) Unless otherwise specified, VI = −11V, IO = 100mA, CI = 2µF, CO = 1µF and Tj = 0 to 125°C
3
AN79Nxx Series
Voltage Regulators
■ Electrical Characteristics at Ta = 25°C (continued)
• AN79N07 (−7V type)
Parameter
Symbol
Conditions
Output voltage
VO
Tj = 25°C
Output voltage tolerance
VO
VI = −9 to −25V, IO = 5 to 200mA
Line regulation
REGIN
Load regulation
REGL
Bias current
IBias
Bias current fluctuation to input
∆IBias(IN)
Bias current fluctuation to load
∆IBias(L)
Output noise voltage
Vno
Ripple rejection ratio
RR
Min
−6.7
Typ
−7
−6.65
Max
−7.3
Unit
V
−7.35
V
VI = −9 to −25V, Tj = 25°C
12
70
mV
VI = −10 to −20V, Tj = 25°C
7
35
mV
IO = 1 to 300mA, Tj = 25°C
20
140
mV
IO = 5 to 200mA, Tj = 25°C
10
70
mV
3
5
mA
0.5
mA
0.1
mA
Tj = 25°C
VI = −10 to −25V, Tj = 25°C
IO = 5 to 200mA, Tj = 25°C
f = 10Hz to 100kHz
VI = −10 to −20V, IO = 50mA,
f = 120Hz
µV
175
dB
59
Minimum input/output voltage difference
VDIF(min)
IO = 200mA, Tj = 25°C
1.1
V
Output short-circuit current
IO(Short)
VI = −35V, Tj = 25°C
10
mA
Peak output current
IO(Peak)
Tj = 25°C
500
mA
Output voltage temperature coefficient
∆VO/Ta
IO = 5mA
− 0.5
mV/°C
Note 1) The specified condition Tj = 25°C means that the test should be carried out within so short a test time (within 10ms) that the
characteristic value drift due to the chip junction temperature rise can be ignored.
Note 2) Unless otherwise specified, VI = −12V, IO = 100mA, CI = 2µF, CO = 1µF and Tj = 0 to 125°C
• AN79N08 (−8V type)
Parameter
Symbol
Conditions
Min
Output voltage
VO
Tj = 25°C
−7.7
Output voltage tolerance
VO
VI = −10.5 to −25V, IO = 5 to 200mA
−7.6
Line regulation
Load regulation
Bias current
REGIN
REGL
IBias
VI = −10.5 to −25V, Tj = 25°C
Typ
−8
13
Max
−8.3
Unit
V
−8.4
V
80
mV
VI = −11 to −21V, Tj = 25°C
8
40
mV
IO = 1 to 300mA, Tj = 25°C
25
160
mV
IO = 5 to 200mA, Tj = 25°C
10
80
mV
3
5
mA
Tj = 25°C
Bias current fluctuation to input
∆IBias(IN)
VI = −10.5 to −25V, Tj = 25°C
0.5
mA
Bias current fluctuation to load
∆IBias(L)
IO = 5 to 200mA, Tj = 25°C
0.1
mA
Output noise voltage
Vno
Ripple rejection ratio
RR
f = 10Hz to 100kHz
VI = −11.5 to −21.5V, IO = 50mA,
f = 120Hz
200
µV
dB
59
Minimum input/output voltage difference
VDIF(min)
IO = 200mA, Tj = 25°C
Output short-circuit current
IO(Short)
VI = −35V, Tj = 25°C
Peak output current
IO(Peak)
Tj = 25°C
500
mA
Output voltage temperature coefficient
∆VO/Ta
IO = 5mA
− 0.6
mV/°C
1.1
V
10
mA
Note 1) The specified condition Tj = 25°C means that the test should be carried out within so short a test time (within 10ms) that the
characteristic value drift due to the chip junction temperature rise can be ignored.
Note 2) Unless otherwise specified, VI = −14V, IO = 100mA, CI = 2µF, CO = 1µF and Tj = 0 to 125°C
4
Voltage Regulators
AN79Nxx Series
■ Electrical Characteristics at Ta = 25°C (continued)
• AN79N09 (−9V type)
Parameter
Symbol
Output voltage
VO
Output voltage tolerance
VO
Line regulation
Load regulation
Bias current
REGIN
REGL
IBias
Conditions
Min
Tj = 25°C
−8.65
VI = −11.5 to −26V, IO = 5 to 200mA
−8.55
VI = −11.5 to −26V, Tj = 25°C
Typ
−9
14
Max
−9.35
Unit
V
−9.45
V
80
mV
VI = −12 to −22V, Tj = 25°C
9
50
mV
IO = 1 to 300mA, Tj = 25°C
25
180
mV
IO = 5 to 200mA, Tj = 25°C
10
90
mV
3
5
mA
Tj = 25°C
Bias current fluctuation to input
∆IBias(IN)
VI = −11.5 to −26V, Tj = 25°C
0.5
mA
Bias current fluctuation to load
∆IBias(L)
IO = 5 to 200mA, Tj = 25°C
0.1
mA
Output noise voltage
Vno
Ripple rejection ratio
RR
f = 10Hz to 100kHz
VI = −12 to −22V, IO = 50mA,
f = 120Hz
µV
225
dB
58
Minimum input/output voltage difference
VDIF(min)
IO = 200mA, Tj = 25°C
1.1
V
Output short-circuit current
IO(Short)
VI = −35V, Tj = 25°C
10
mA
Peak output current
IO(Peak)
Tj = 25°C
500
mA
Output voltage temperature coefficient
∆VO/Ta
IO = 5mA
− 0.6
mV/°C
Note 1) The specified condition Tj = 25°C means that the test should be carried out within so short a test time (within 10ms) that the
characteristic value drift due to the chip junction temperature rise can be ignored.
Note 2) Unless otherwise specified, VI = −15V, IO = 100mA, CI = 2µF, CO = 1µF and Tj = 0 to 125°C
• AN79N10 (−10V type)
Parameter
Symbol
Conditions
Min
Output voltage
VO
Tj = 25°C
−9.6
Output voltage tolerance
VO
VI = −12.5 to −27V, IO = 5 to 200mA
−9.5
Line regulation
Load regulation
Bias current
REGIN
REGL
IBias
Typ
−10
Max
−10.4
Unit
V
−10.5
V
80
mV
VI = −12.5 to −27V, Tj = 25°C
15
VI = −13 to −23V, Tj = 25°C
10
50
mV
IO = 1 to 300mA, Tj = 25°C
25
200
mV
IO = 5 to 200mA, Tj = 25°C
10
100
mV
Tj = 25°C
3.0
5
mA
Bias current fluctuation to input
∆IBias(IN)
VI = −12.5 to −27V, Tj = 25°C
0.5
mA
Bias current fluctuation to load
∆IBias(L)
IO = 5 to 200mA, Tj = 25°C
0.1
mA
Output noise voltage
Vno
Ripple rejection ratio
RR
f = 10Hz to 100kHz
VI = −13 to −23V, IO = 50mA,
f = 120Hz
250
µV
dB
58
Minimum input/output voltage difference
VDIF(min)
IO = 200mA, Tj = 25°C
Output short-circuit current
IO(Short)
VI = −35V, Tj = 25°C
Peak output current
IO(Peak)
Tj = 25°C
500
mA
Output voltage temperature coefficient
∆VO/Ta
IO = 5mA
− 0.7
mV/°C
1.1
V
10
mA
Note 1) The specified condition Tj = 25°C means that the test should be carried out within so short a test time (within 10ms) that the
characteristic value drift due to the chip junction temperature rise can be ignored.
Note 2) Unless otherwise specified, VI = −16V, IO = 100mA, CI = 2µF, CO = 1µF and Tj = 0 to 125°C
5
AN79Nxx Series
Voltage Regulators
■ Electrical Characteristics at Ta = 25°C (continued)
• AN79N12 (−12V type)
Parameter
Symbol
Conditions
Min
Output voltage
VO
Tj = 25°C
−11.5
Output voltage tolerance
VO
VI = −14.5 to −30V, IO = 5 to 200mA
−11.4
Line regulation
Load regulation
Bias current
REGIN
REGL
IBias
Typ
−12
Max
−12.5
Unit
V
−12.6
V
80
mV
VI = −14.5 to −30V, Tj = 25°C
15
VI = −15 to −25V, Tj = 25°C
10
50
mV
IO = 1 to 300mA, Tj = 25°C
25
240
mV
IO = 5 to 200mA, Tj = 25°C
10
120
mV
3
5
mA
Tj = 25°C
Bias current fluctuation to input
∆IBias(IN)
VI = −14.5 to −30V, Tj = 25°C
0.5
mA
Bias current fluctuation to load
∆IBias(L)
IO = 5 to 200mA, Tj = 25°C
0.1
mA
Output noise voltage
Vno
Ripple rejection ratio
RR
f = 10Hz to 100kHz
VI = −15 to −25V, IO = 50mA,
f = 120Hz
µV
300
dB
57
Minimum input/output voltage difference
VDIF(min)
IO = 200mA, Tj = 25°C
1.1
V
Output short-circuit current
IO(Short)
VI = −35V, Tj = 25°C
10
mA
Peak output current
IO(Peak)
Tj = 25°C
500
mA
Output voltage temperature coefficient
∆VO/Ta
IO = 5mA
− 0.8
mV/°C
Note 1) The specified condition Tj = 25°C means that the test should be carried out within so short a test time (within 10ms) that the
characteristic value drift due to the chip junction temperature rise can be ignored.
Note 2) Unless otherwise specified, VI = −19V, IO = 100mA, CI = 2µF, CO = 1µF and Tj = 0 to 125°C
• AN79N15 (−15V type)
Parameter
Symbol
Conditions
Min
Output voltage
VO
Tj = 25°C
Output voltage tolerance
VO
VI = −17.5 to −30V, IO = 5 to 200mA −14.25
Line regulation
Load regulation
Bias current
REGIN
REGL
IBias
Bias current fluctuation to input
∆IBias(IN)
Bias current fluctuation to load
∆IBias(L)
Output noise voltage
Vno
Ripple rejection ratio
RR
−14.4
Typ
−15
Max
−15.6
Unit
V
−15.75
V
80
mV
VI = −17.5 to −30V, Tj = 25°C
16
VI = −18 to −28V, Tj = 25°C
11
50
mV
IO = 1 to 300mA, Tj = 25°C
25
240
mV
IO = 5 to 200mA, Tj = 25°C
10
120
mV
3
5
mA
0.5
mA
0.1
mA
Tj = 25°C
VI = −17.5 to −30V, Tj = 25°C
IO = 5 to 200mA, Tj = 25°C
f = 10Hz to 100kHz
VI = −18 to −28V, IO = 50mA,
f = 120Hz
375
µV
dB
56
VDIF(min)
IO = 200mA, Tj = 25°C
Output short-circuit current
IO(Short)
VI = −35V, Tj = 25°C
Peak output current
IO(Peak)
Tj = 25°C
500
mA
Output voltage temperature coefficient
∆VO/Ta
IO = 5mA
− 0.9
mV/°C
Minimum input/output voltage difference
1.1
V
10
mA
Note 1) The specified condition Tj = 25°C means that the test should be carried out within so short a test time (within 10ms) that the
characteristic value drift due to the chip junction temperature rise can be ignored.
Note 2) Unless otherwise specified, VI = −23V, IO = 100mA, CI = 2µF, CO = 1µF and Tj = 0 to 125°C
6
Voltage Regulators
AN79Nxx Series
■ Electrical Characteristics at Ta = 25°C (continued)
• AN79N18 (−18V type)
Parameter
Symbol
Conditions
Min
Output voltage
VO
Tj = 25°C
−17.3
Output voltage tolerance
VO
VI = −21 to −33V, IO = 5 to 200mA
−17.1
Line regulation
REGIN
Load regulation
REGL
Bias current
IBias
Typ
−18
Max
−18.7
Unit
V
−18.9
V
VI = −21 to −33V, Tj = 25°C
18
80
mV
VI = −22 to −32V, Tj = 25°C
13
50
mV
IO = 1 to 300mA, Tj = 25°C
30
300
mV
IO = 5 to 200mA, Tj = 25°C
10
150
mV
3
5
mA
Tj = 25°C
Bias current fluctuation to input
∆IBias(IN)
VI = −21 to −33V, Tj = 25°C
0.5
mA
Bias current fluctuation to load
∆IBias(L)
IO = 5 to 200mA, Tj = 25°C
0.1
mA
Output noise voltage
Vno
Ripple rejection ratio
RR
f = 10Hz to 100kHz
VI = −22 to −32V, IO = 50mA,
f = 120Hz
µV
450
dB
55
Minimum input/output voltage difference
VDIF(min)
IO = 200mA, Tj = 25°C
1.1
V
Output short-circuit current
IO(Short)
VI = −35V, Tj = 25°C
10
mA
Peak output current
IO(Peak)
Tj = 25°C
500
mA
Output voltage temperature coefficient
∆VO/Ta
IO = 5mA
−1
mV/°C
Note 1) The specified condition Tj = 25°C means that the test should be carried out within so short a test time (within 10ms) that the
characteristic value drift due to the chip junction temperature rise can be ignored.
Note 2) Unless otherwise specified, VI = −27V, IO = 100mA, CI = 2µF, CO = 1µF and Tj = 0 to 125°C
• AN79N20 (−20V type)
Parameter
Symbol
Conditions
Output voltage
VO
Tj = 25°C
Output voltage tolerance
VO
VI = −23 to −35V, IO = 5 to 200mA
Line regulation
REGIN
Load regulation
REGL
Bias current
IBias
Bias current fluctuation to input
∆IBias(IN)
Bias current fluctuation to load
∆IBias(L)
Output noise voltage
Vno
Ripple rejection ratio
RR
Min
−19.2
Typ
−20
−19
Max
−20.8
Unit
V
−21
V
VI = −23 to −35V, Tj = 25°C
19
80
mV
VI = −24 to −34V, Tj = 25°C
14
70
mV
IO = 1 to 300mA, Tj = 25°C
30
300
mV
IO = 5 to 200mA, Tj = 25°C
10
150
mV
3
5
mA
0.5
mA
0.1
mA
Tj = 25°C
VI = −23 to −35V, Tj = 25°C
IO = 5 to 200mA, Tj = 25°C
f = 10Hz to 100kHz
VI = −24 to −34V, IO = 50mA,
f = 120Hz
500
µV
dB
54
Minimum input/output voltage difference
VDIF(min)
IO = 200mA, Tj = 25°C
1.1
V
Output short-circuit current
IO(Short)
VI = −35V, Tj = 25°C
10
mA
Peak output current
IO(Peak)
Tj = 25°C
500
mA
Output voltage temperature coefficient
∆VO/Ta
IO = 5mA
−1
mV/°C
Note 1) The specified condition Tj = 25°C means that the test should be carried out within so short a test time (within 10ms) that the
characteristic value drift due to the chip junction temperature rise can be ignored.
Note 2) Unless otherwise specified, VI = −29V, IO = 100mA, CI = 2µF, CO = 1µF and Tj = 0 to 125°C
7
AN79Nxx Series
Voltage Regulators
■ Electrical Characteristics at Ta = 25°C (continued)
• AN79N24 (−24V type)
Parameter
Symbol
Conditions
Min
−22.8
Output voltage
VO
Tj = 25°C
Output voltage tolerance
VO
VI = −27 to −38V, IO = 5 to 200mA
Line regulation
REGIN
Load regulation
REGL
Bias current
IBias
Bias current fluctuation to input
Bias current fluctuation to load
−23
V
V
mV
VI = −27 to −37V, Tj = 25°C
15
70
mV
IO = 1 to 300mA, Tj = 25°C
30
300
mV
IO = 5 to 200mA, Tj = 25°C
10
150
mV
3
5
mA
0.5
mA
0.1
mA
Tj = 25°C
∆IBias(L)
RR
−25
−25.2
80
IO = 5 to 200mA, Tj = 25°C
Ripple rejection ratio
−24
Unit
20
VI = −27 to −38V, Tj = 25°C
Vno
Max
VI = −27 to −38V, Tj = 25°C
∆IBias(IN)
Output noise voltage
Typ
f = 10Hz to 100kHz
VI = −28 to −38V, IO = 50mA,
f = 120Hz
µV
600
dB
54
Minimum input/output voltage difference
VDIF(min)
IO = 200mA, Tj = 25°C
1.1
V
Output short-circuit current
IO(Short)
VI = −35V, Tj = 25°C
10
mA
Peak output current
IO(Peak)
Tj = 25°C
500
mA
Output voltage temperature coefficient
∆VO/Ta
IO = 5mA
−1
mV/°C
Note 1) The specified condition Tj = 25°C means that the test should be carried out within so short a test time (within 10ms) that the
characteristic value drift due to the chip junction temperature rise can be ignored.
Note 2) Unless otherwise specified, VI = −33V, IO = 100mA, CI = 2µF, CO = 1µF and Tj = 0 to 125°C
8
Rth(j-c) =
15°C/W (max.)
R
(1) th(j-a) =
100°C/W (max.)
6
(2)
4
(3)
2
(4)
0
0
40
80
120
Ambient temperature Ta (°C)
8
160
Input transient response
AN79N05
AN79N05
20
15
1.2
IO = 300mA
1.0
IO
=1
00
mA
0m
A
IO =
5m
A
IO
0.8
=5
0.6
0.4
−50
0
50
100
150
Junction temperature Tj (°C)
10
5
10
0
−10
−20
0
2
4
6
Time t (µs)
8
10
Input voltage VI (V)
Power dissipation PD (W)
(1) Infinite heat sink
(2) 5°C/W heat sink
(3) 15°C/W heat sink
(4) Without heat sink
VDIF(min)  Tj
1.4
Output voltage fluctuation (mV)
PD  Ta
10
Minimum input/output voltage difference VDIF(min) (V)
■ Main Characteristics
Voltage Regulators
AN79Nxx Series
■ Main Characteristics (continued)
RR  f
0.6
Output voltage fluctuation (V)
0.3
0
1
0
−1
−2
120
Ripple rejection ratio RR (dB)
AN79N05
Load current IO (A)
Load transient response
AN79N05
IO = 50mA
100
80
60
40
20
0
0
10
20
30
40
10
50
100
1k
10k
100k
Frequency f (Hz)
Time t (µs)
■ Basic Regulator Circuit
−VI
Input
−VO
Output
AN79Nxx
CI
−
−
+
Common +
CO
Connect CI of 2µF when the input line is long.
CO improves the transient response. 1µF
■ Usage Notes
1. Cautions for a basic circuit
Di
VI
VO
3
1
CI
2
Figure 1
CO
CI: When a wiring from a smoothing circuit to a three-pin regulator
is long, it is likely to oscillate at output. A capacitor of 0.1µF to
0.47µF should be connected near an input pin.
CO: Deadly needed to prevent from oscillation (0.33µF to 1.0µF). It
is recommended to use a capacitor of a small internal impedance (ex. tantalum capacitor) when using it under a low temperature.
When any sudden change of load current is likely to occur, connect an electrolytic capacitor of 10µF to 100µF to improve a
transitional response of output voltage.
Di: Normally unnecessary. But add it in the case that there is a
residual voltage at the output capacitor Co even after switching
off the supply power because a current is likely to flow into an
output pin of the IC and damage the IC.
9
AN79Nxx Series
Voltage Regulators
■ Usage Notes (continued)
2. Other caution items
1) Short-circuit between the input pin and GND pin
If the input pin is short-circuitted to GND or is cut
off when a large capacitance capacitor has been connected to the IC's load, a voltage of a capacitor connected to an output pin is applied between input/output of the IC and this likely results in damage of the
IC. It is necessary, therefore, to connect a diode, as
shown in figure 2, to counter the reverse bias between
input/output pins.
In
3
1
2
GND
Output
Out
−
+
CO
Figure 2
2) Floating of GND pin
If a GND pin is made floating in an operating mode, an unstabilized input voltage is outputted. In this case, a
thermal protection circuit inside the IC does not normally operate. In this state, if the load is short-circuited or
overloaded, it is likely to damage the IC.
■ Application Circuit Example
−VI
Input
Output
AN79Nxx
V O'
−
+
−
+
Common
1µF
R
2µF
IQ
IO
| IO | =
10
VO'
+ IQ
R