January 1999 TOKO, Inc.
Page 1
TK715xx
GND
VIN
VOUT
THERMAL
PROTECTION
+
-
+
-
BANDGAP
REFERENCE
FEATURES
s
High Voltage Precision at
2.0% or
60 mV
s
Very Low Quiescent Current
s
Very Low Dropout Voltage
s
Reverse Bias Protection
s
Miniature Package (SOT-23-3)
s
Short Circuit Protection
s
High Ripple Rejection
APPLICATIONS
s
Battery Powered Systems
s
Cellular Telephones
s
Pagers
s
Personal Communications Equipment
s
Portable Instrumentation
s
Portable Consumer Equipment
s
Radio Control Systems
s
Toys
s
Low Voltage Systems
BLOCK DIAGRAM
TK715xxS
GND
VOUT
VIN
DESCRIPTION
The TK715xx is a low dropout linear regulator housed in a
small SOT-23-3 package, rated at 350 mW. An internal
PNP transistor is used to achieve a low dropout voltage of
105 mV (typ.) at 50 mA load current. This device offers high
precision output voltage of
2.0 % or
60 mV. The
TK715xx has a very low quiescent current of 25
A (typ.)
at no load. The low quiescent current and dropout voltage
make this part ideal for battery powered applications. The
internal reverse bias protection eliminates the requirement
for a reverse voltage protection diode, saving cost and
board space. The high 64 dB ripple rejection and low noise
provide enhanced performance for critical applications.
TK715 SCL
ORDERING INFORMATION
VOLTAGE CODE
19 = 1.9 V
37 = 3.7 V
20 = 2.0 V
38 = 3.8 V
21 = 2.1 V
39 = 3.9 V
22 = 2.2 V
40 = 4.0 V
23 = 2.3 V
41 = 4.1 V
24 = 2.4 V
42 = 4.2 V
25 = 2.5 V
43 = 4.3 V
26 = 2.6 V
44 = 4.4 V
27 = 2.7 V
45 = 4.5 V
28 = 2.8 V
46 = 4.6 V
29 = 2.9 V
47 = 4.7 V
30 = 3.0 V
48 = 4.8 V
31 = 3.1 V
49 = 4.9 V
32 = 3.2 V
50 = 5.0 V
33 = 3.3 V
60 = 6.0 V
34 = 3.4 V
70 = 7.0 V
35 = 3.5 V
80 = 8.0 V
36 = 3.6 V
90 = 9.0 V
Voltage Code
Tape/ Reel Code
Temp. Code
Package Code
TAPE/REEL CODE
L: Tape Left
TEMPERATURE CODE
C -30 to +80 C
PACKAGE CODE
S : SOT-23-3
20P
LOW DROPOUT VOLTAGE REGULATOR
Page 2
January 1999 TOKO, Inc.
TK715xx
ABSOLUTE MAXIMUM RATINGS (V
OUT
5.0 V)
Supply Voltage .............................................. -0.4 to 16 V
Power Dissipation (Note 1) ................................ 350 mW
Reverse Bias .............................................................. 8 V
Storage Temperature (Ambient) ............... -55 to +150
C
Operating Temperature (Ambient) .............. -30 to +80
C
Max. Operating Temperature (Junction) ............... 125
C
Operating Voltage Range ............................ 1.8 to 14.0 V
Junction Temperature ........................................... 150
C
Lead Soldering Temperature (10 s) ...................... 235
C
TK715xx ELECTRICAL CHARACTERISTICS (V
OUT
5.0 V)
Test conditions: T
A
= 25
C, unless otherwise specified.
Note 1: Power dissipation is 350 mW when mounted as recommended. Derate at 2.8 mW/
C for operation above 25
C.
Note 2: Refer to "Definition of Terms."
Note 3: Ripple rejection and noise voltage are affected by the value and characteristics of the capacitor used.
Note 4: Ripple rejection is measured at V
R
= 200 mVrms, V
IN
= V
OUT(TYP)
+ 2 V, I
OUT
= 10 mA, C
L
= 4.7
F, f = 100 Hz.
Gen. Note: Parameters with min. or max. values are 100% tested at T
A
= 25
C.
L
O
B
M
Y
S
R
E
T
E
M
A
R
A
P
S
N
O
I
T
I
D
N
O
C
T
S
E
T
N
I
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P
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T
X
A
M
S
T
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U
I
Q
t
n
e
r
r
u
C
t
n
e
c
s
e
i
u
Q
I
T
U
O
V
,
A
m
0
=
T
U
O
V
0
.
4
5
2
5
4
A
I
T
U
O
V
,
A
m
0
=
T
U
O
V
1
.
4
0
3
0
5
A
I
D
N
G
t
n
e
r
r
u
C
d
n
u
o
r
G
I
T
U
O
A
m
0
5
=
4
.
1
5
.
2
A
m
V
T
U
O
e
g
a
t
l
o
V
t
u
p
t
u
O
I
T
U
O
A
m
0
1
=
1
e
l
b
a
T
e
e
S
V
g
e
R
e
n
i
L
n
o
i
t
a
l
u
g
e
R
e
n
i
L
V
N
I
V
=
)
P
Y
T
(
T
U
O
o
t
V
1
+
V
)
P
Y
T
(
T
U
O
V
6
+
0
.
1
0
1
V
m
g
e
R
d
a
o
L
n
o
i
t
a
l
u
g
e
R
d
a
o
L
I
T
U
O
)
2
e
t
o
N
(
,
A
m
0
5
o
t
5
=
0
1
0
3
V
m
I
T
U
O
)
2
e
t
o
N
(
,
A
m
0
0
1
o
t
5
=
0
2
0
5
V
m
V
P
O
R
D
e
g
a
t
l
o
V
t
u
o
p
o
r
D
I
T
U
O
A
m
0
5
=
5
0
1
.
0
0
8
1
0
.
V
I
T
U
O
V
,
A
m
0
0
1
=
T
U
O
V
4
.
2
5
8
1
.
0
0
8
2
.
0
V
I
T
U
O
V
,
A
m
0
0
1
=
T
U
O
V
4
.
2
<
5
8
1
.
0
0
3
3
.
0
V
I
T
U
O
t
n
e
r
r
u
C
t
u
p
t
u
O
s
u
o
u
n
i
t
n
o
C
0
0
1
A
m
R
R
n
o
i
t
c
e
j
e
R
e
l
p
p
i
R
)
4
,
3
s
e
t
o
N
(
4
6
B
d
V
T
U
O
/
T
t
n
e
i
c
i
f
f
e
o
C
e
r
u
t
a
r
e
p
m
e
T
I
T
U
O
A
m
0
1
=
5
3
C
/
m
p
p
January 1999 TOKO, Inc.
Page 3
TK715xx
ABSOLUTE MAXIMUM RATINGS (V
OUT
6.0 V)
Supply Voltage .............................................. -0.4 to 16 V
Power Dissipation (Note 1) ................................ 350 mW
Reverse Bias .............................................................. 8 V
Storage Temperature (Ambient) ............... -55 to +150
C
Operating Temperature (Ambient) ..............-30 to +80
C
Max. Operating Temperature (Junction) ............... 125
C
Operating Voltage Range ............................ 2.5 to 14.0 V
Junction Temperature ........................................... 150
C
Lead Soldering Temperature (10 s) ...................... 235
C
TK715xx ELECTRICAL CHARACTERISTICS (V
OUT
6.0 V)
Test conditions: T
A
= 25
C, unless otherwise specified.
Note 1: Power dissipation is 350 mW when mounted as recommended. Derate at 2.8 mW/
C for operation above 25
C.
Note 2: Refer to "Definition of Terms."
Note 3: Ripple rejection and noise voltage are affected by the value and characteristics of the capacitor used.
Note 4: Ripple rejection is measured at V
R
= 200 mVrms, V
IN
= V
OUT(TYP)
+ 2 V, I
OUT
= 10 mA, C
L
= 4.7
F, f = 100 Hz.
Gen. Note: Parameters with min. or max. values are 100% tested at T
A
= 25
C.
L
O
B
M
Y
S
R
E
T
E
M
A
R
A
P
S
N
O
I
T
I
D
N
O
C
T
S
E
T
N
I
M
P
Y
T
X
A
M
S
T
I
N
U
I
Q
t
n
e
r
r
u
C
t
n
e
c
s
e
i
u
Q
I
T
U
O
A
m
0
=
2
3
0
6
A
I
D
N
G
t
n
e
r
r
u
C
d
n
u
o
r
G
I
T
U
O
A
m
0
5
=
4
.
1
5
.
2
A
m
V
T
U
O
e
g
a
t
l
o
V
t
u
p
t
u
O
I
T
U
O
A
m
0
1
=
1
e
l
b
a
T
e
e
S
V
g
e
R
e
n
i
L
n
o
i
t
a
l
u
g
e
R
e
n
i
L
V
N
I
V
=
)
P
Y
T
(
T
U
O
o
t
V
1
+
V
)
P
Y
T
(
T
U
O
V
4
1
x
a
M
r
o
V
6
+
0
.
3
V
m
g
e
R
d
a
o
L
n
o
i
t
a
l
u
g
e
R
d
a
o
L
I
T
U
O
)
2
e
t
o
N
(
,
A
m
0
5
o
t
5
=
0
1
0
3
V
m
I
T
U
O
)
2
e
t
o
N
(
,
A
m
0
0
1
o
t
5
=
0
2
0
5
V
m
V
P
O
R
D
e
g
a
t
l
o
V
t
u
o
p
o
r
D
I
T
U
O
A
m
0
5
=
5
0
1
.
0
0
8
1
0
.
V
I
T
U
O
A
m
0
0
1
=
5
8
1
.
0
0
8
2
.
0
V
I
T
U
O
t
n
e
r
r
u
C
t
u
p
t
u
O
s
u
o
u
n
i
t
n
o
C
0
0
1
A
m
R
R
n
o
i
t
c
e
j
e
R
e
l
p
p
i
R
)
4
,
3
s
e
t
o
N
(
4
6
B
d
V
T
U
O
/
T
t
n
e
i
c
i
f
f
e
o
C
e
r
u
t
a
r
e
p
m
e
T
I
T
U
O
A
m
0
1
=
5
3
C
/
m
p
p
Page 4
January 1999 TOKO, Inc.
TK715xx
TK715xx ELECTRICAL CHARACTERISTICS TABLE 1
Output
Voltage
V
OUT(MIN)
V
OUT(MAX)
Test
Voltage
Code
Voltage
1.9 V
19
1.840 V
1.960 V
2.9 V
2.0 V
20
1.940 V
2.060 V
3.0 V
2.1 V
21
2.040 V
2.160 V
3.1 V
2.2 V
22
2.140 V
2.260 V
3.2 V
2.3 V
23
2.240 V
2.360 V
3.3 V
2.4 V
24
2.340 V
2.460 V
3.4 V
2.5 V
25
2.440 V
2.560 V
3.5 V
2.6 V
26
2.540 V
2.660 V
3.6 V
2.7 V
27
2.640 V
2.760 V
3.7 V
2.8 V
28
2.740 V
2.860 V
3.8 V
2.9 V
29
2.840 V
2.960 V
3.9 V
3.0 V
30
2.940 V
3.060 V
4.0 V
3.1 V
31
3.040 V
3.160 V
4.1 V
3.2 V
32
3.140 V
3.260 V
4.2 V
3.3 V
33
3.240 V
3.360 V
4.3 V
3.4 V
34
3.335 V
3.465 V
4.4 V
3.5 V
35
3.435 V
3.565 V
4.5 V
3.6 V
36
3.535 V
3.665 V
4.6 V
Output
Voltage
V
OUT(MIN)
V
OUT(MAX)
Test
Voltage
Code
Voltage
3.7 V
37
3.630 V
3.770 V
4.7 V
3.8 V
38
3.725 V
3.875 V
4.8 V
3.9 V
39
3.825 V
3.975 V
4.9 V
4.0 V
40
3.920 V
4.080 V
5.0 V
4.1 V
41
4.020 V
4.180 V
5.1 V
4.2 V
42
4.120 V
4.280 V
5.2 V
4.3 V
43
4.215 V
4.385 V
5.3 V
4.4 V
44
4.315 V
4.485 V
5.4 V
4.5 V
45
4.410 V
4.590 V
5.5 V
4.6 V
46
4.510 V
4.690 V
5.6 V
4.7 V
47
4.605 V
4.795 V
5.7 V
4.8 V
48
4.705 V
4.895 V
5.8 V
4.9 V
49
4.800 V
5.000 V
5.9 V
5.0 V
50
4.900 V
5.100 V
6.0 V
6.0 V
60
5.880 V
6.120 V
7.0 V
7.0 V
70
6.860 V
7.140 V
8.0 V
8.0 V
80
7.840 V
8.160 V
9.0 V
9.0 V
90
8.820 V
9.180 V
9.0 V
January 1999 TOKO, Inc.
Page 5
TK715xx
TYPICAL PERFORMANCE CHARACTERISTICS
T
A
= 25
C, unless otherwise specified.
TEST CIRCUIT
IOUT
VIN
VIN
VOUT
+
CIN
0.1 F
VOUT
+
IIN
+
_
GND
CL
2.2 F
V
OUT
(5 mV/ DIV)
LOAD REGULATION
IOUT (mA)
0 50 100
VOUT TYPICAL
V
OUT
(V)
3
5
SHORT CIRCUIT PROTECTION
IOUT (mA)
1
0 100 200
4
2
0
V
OUT
(25 mV/ DIV)
OUTPUT VOLTAGE
VS
.
INPUT VOLTAGE
VIN (V) (50 mV/DIV)
0 VIN = VOUT
VOUT TYPICAL
IOUT = 90 mA
IOUT = 0 mA
IOUT = 60 mA
IOUT = 30 mA
V
OUT
(
5
0
m
V/
DIV)
LINE REGULATION
VIN (V)
0 10 20
VOUT TYPICAL
I REV
(
A)
60
100
REVERSE BIAS CURRENT RANGE
(VIN = 0 V)
VREV (V)
20
0 5 10
80
40
0
VOUT = 2.0 V
VOUT = 8.0 V
I Q
(
m
A)
2
QUIESCENT CURRENT
VS.
INPUT VOLTAGE
VIN (V)
0 5 10
1
0
IOUT = 0 mA
VOUT = 3 V
Page 6
January 1999 TOKO, Inc.
TK715xx
715xx
CL
4.7 F
VOUT
VIN
CIN
0.1 to 1 F
RIPPLE REJECTION CIRCUIT
V
DROP
(
m
V)
-100
0
OUTPUT CURRENT
VS.
DROPOUT VOLTAGE
IOUT (mA)
-200
0 50 100
I GND
(
A)
200
500
GROUND CURRENT 1
VS.
OUTPUT CURRENT
IOUT (mA)
100
0 5 10 15 20 25
400
300
0
I GND
(
m
A)
2
5
GROUND CURRENT 2
VS.
OUTPUT CURRENT
IOUT (mA)
1
0 20 40 60 80 100
4
3
0
I OUT
(
m
A)
160
220
MAXIMUM OUTPUT CURRENT
VS.
TEMPERATURE
TA (
C)
150
-50 0 50 100
200
180
VOUT IS 2.7 V OR MORE
NOISE
(
V)
140
200
NOISE LEVEL
VS.
OUTPUT CURRENT
IOUT (mA)
120
0 50 100
180
160
100
1 F
2.2 F
3.3 F
4.7 F
10 F
CL =
CIN =10 F
BW = 10 Hz to 80 kHz
NOISE
(
V)
140
200
NOISE LEVEL
VS.
CL
CL (F)
120
1.0 5.0 10
180
160
100
5 mA
10 mA
30 mA
60 mA
90 mA
CIN =10 F
BW = 10 Hz to 80 kHz
IOUT =
RIPPLE REJECTION
0.01 0.1 1 10
f (kHz)
-80
RR (dB)
-20
-60
-40
0
-100
IOUT = 10 mA
CL = 4.7 F
V
OUT
(
m
V)
-10
OUTPUT VOLTAGE
VS.
TEMPERATURE
TA (
C)
-20
-50 0 50 100
10
0
20
-30
3.0 V
2.9 V
TYPICAL PERFORMANCE CHARACTERISTICS (CONT.)
T
A
= 25
C, unless otherwise specified.
January 1999 TOKO, Inc.
Page 7
TK715xx
dB
NOISE SPECTRUM
f (kHz)
-100
0 500 k 1 M
-50
CL = 4.7 F, IOUT = 60 mA
CL = 4.7 F, IOUT = 5 mA
SPECTRUM ANALYZER BACK-
GROUND NOISE
RB = 1 kHz, VB = 100 Hz
LINE VOLTAGE STEP RESPONSE
TIME (50 s/ DIV)
V
IN
V
OUT (10 mV/ DIV)
V
OUT
C
L = 4.7 F
IOUT = 10 mA
VOUT + 2 V
VOUT + 1 V
LOAD CURRENT STEP RESPONSE 2
TIME (50 s/ DIV)
I OUT
V
OUT1
V
OUT (20 mV/ DIV)
NOTE: VOUT2 DELAYED 50 s FOR CLARITY
V
OUT2
IOUT = 0 to 100 mA
IOUT = 0 to 30 mA
CL =4.7 F
LOAD CURRENT STEP RESPONSE 1
TIME (50 s/ DIV)
I OUT
V
OUT1
V
OUT (20 mV/ DIV)
CL =4.7 F
IOUT = 5 to 100 mA
IOUT = 5 to 30 mA
NOTE: VOUT2 DELAYED 50 s FOR CLARITY
V
OUT2
TYPICAL PERFORMANCE CHARACTERISTICS (CONT.)
T
A
= 25
C, unless otherwise specified.
Page 8
January 1999 TOKO, Inc.
TK715xx
DEFINITION AND EXPLANATION OF TECHNICAL TERMS
OUTPUT VOLTAGE (V
OUT
)
The output voltage is specified with V
IN
= (V
OUT(TYP)
+ 1 V)
and I
OUT
= 30 mA.
DROPOUT VOLTAGE (V
DROP
)
The dropout voltage is the difference between the input
voltage and the output voltage at which point the regulator
starts to fall out of regulation. Below this value, the output
voltage will fall as the input voltage is reduced. It is
dependent upon the load current and the junction
temperature.
CONTINUOUS OUTPUT CURRENT (I
OUT
)
Normal operating output current. This is limited by package
power dissipation.
PULSE OUTPUT CURRENT (I
OUT(PULSE)
)
Maximum pulse width 5 ms at V
OUT
above 2.0 V, duty cycle
12.5%: pulse load only.
LINE REGULATION (Line Reg)
Line regulation is the ability of the regulator to maintain a
constant output voltage as the input voltage changes. The
line regulation is specified as the input voltage is changed
from V
IN
= V
OUT(TYP)
+ 1 V to V
IN
= V
OUT(TYP)
+ 6 V or V
IN
=
max 14 V.
LOAD REGULATION (Load Reg)
Load regulation is the ability of the regulator to maintain a
constant output voltage as the load current changes. It is
a pulsed measurement to minimize temperature effects
with the input voltage set to V
IN
= V
OUT(TYP)
+1 V. The load
regulation is specified under two output current step
conditions of 1 mA to 60 mA and 1 mA to 100 mA.
QUIESCENT CURRENT (I
Q
)
The quiescent current is the current which flows through
the ground terminal under no load conditions (I
OUT
= 0 mA).
GROUND CURRENT (I
GND
)
Ground current is the current which flows through the
ground pin(s). It is defined as I
IN
- I
OUT
, excluding control
current.
RIPPLE REJECTION RATIO (RR)
Ripple rejection is the ability of the regulator to attenuate
the ripple content of the input voltage at the output. It is
specified with 200 mVrms, 100 Hz superimposed on the
input voltage, where V
IN
= V
OUT(TYP)
+ 2.0 V. The output
decoupling capacitor is set to 4.7
F and the load current
is set to 5 mA. Ripple rejection is the ratio of the ripple
content of the output vs. the input and is expressed in dB.
REVERSE VOLTAGE PROTECTION
Reverse voltage protection prevents damage due to the
output voltage being higher than the input voltage. This
fault condition can occur when the output capacitor remains
charged and the input is reduced to zero, or when an
external voltage higher than the input voltage is applied to
the output side.
REDUCTION OF OUTPUT NOISE
Although the architecture of the Toko regulators are
designed to minimize semiconductor noise, further
reduction can be achieved by the selection of external
components. The obvious solution is to increase the size
of the output capacitor. Please note that several parameters
are affected by the value of the capacitors and bench
testing is recommended when deviating from standard
values.
PACKAGE POWER DISSIPATION (P
D
)
This is the power dissipation level at which the thermal
sensor is activated. The IC contains an internal thermal
sensor which monitors the junction temperature. When the
junction temperature exceeds the monitor threshold of
150
C, the IC is shut down. The junction temperature
rises as the difference between the input power (V
IN
x I
IN
)
and the output power (V
OUT
x I
OUT
) increases. The rate of
temperature rise is greatly affected by the mounting pad
configuration on the PCB, the board material, and the
ambient temperature. When the IC mounting has good
thermal conductivity, the junction temperature will be low
even if the power dissipation is great. When mounted on
the recommended mounting pad, the power dissipation of
the SOT-23-3 is increased to 350 mW. For operation at
ambient temperatures over 25
C, the power dissipation of
the SOT-23-3 device should be derated at 2.8 mW/
C. To
January 1999 TOKO, Inc.
Page 9
TK715xx
DEFINITION AND EXPLANATION OF TECHNICAL TERMS (CONT.)
determine the power dissipation for shutdown when
mounted, attach the device on the actual PCB and
deliberately increase the output current (or raise the input
voltage) until the thermal protection circuit is activated.
Calculate the power dissipation of the device by subtracting
the output power from the input power. These
measurements should allow for the ambient temperature
of the PCB. The value obtained from P
D
/(150
C - T
A
) is the
derating factor. The PCB mounting pad should provide
maximum thermal conductivity in order to maintain low
device temperatures. As a general rule, the lower the
temperature, the better the reliability of the device. The
thermal resistance when mounted is expressed as follows:
T
j
= 0
jA
x P
D
+ T
A
For Toko ICs, the internal limit for junction temperature is
150
C. If the ambient temperature (T
A
) is 25
C, then:
150
C = 0
jA
x P
D
+ 25
C
0
jA
= 125
C/ P
D
P
D
is the value when the thermal sensor is activated. A
simple way to determine P
D
is to calculate V
IN
x I
IN
when
the output side is shorted. Input current gradually falls as
temperature rises. You should use the value when thermal
equilibrium is reached.
The range of usable currents can also be found from the
graph below.
Procedure:
1) Find P
D
2) P
D1
is taken to be P
D
x (~ 0.8 - 0.9)
3) Plot P
D1
against 25
C
4) Connect P
D1
to the point corresponding to the 150
C
with a straight line.
5) In design, take a vertical line from the maximum
operating temperature (e.g., 75
C) to the derating
curve.
6) Read off the value of P
D
against the point at which the
vertical line intersects the derating curve. This is taken
as the maximum power dissipation, D
PD
.
The maximum operating current is:
I
OUT
= (D
PD
/ (V
IN(MAX)
-
V
OUT
)
SOT-23-3 POWER DISSIPATION CURVE
PD
DPD
25
50
75
150
(mW)
TA (
C)
3
6
5
4
0 50 100 150
TA (
C)
P
D
(mW)
0
300
500
100
200
400
MOUNTED AS
SHOWN
FREE AIR
Page 10
January 1999 TOKO, Inc.
TK715xx
TK715xxS
CL
ESR
APPLICATION INFORMATION
INPUT-OUTPUT CAPACITORS
Linear regulators require input and output capacitors in order to maintain regulator loop stability. The output capacitor
should be selected within the Equivalent Series Resistance (ESR) range as shown in the graphs below for stable
operation. When a ceramic capacitor is connected in parallel with the output capacitor, a maximum of 1000 pF is
recommended. This is because the ceramic capacitor's electrical characteristics (capacitance and ESR) vary widely over
temperature. If a large ceramic capacitor is used, a resistor should be connected in series with it to bring it into the stable
operating area shown in the graphs below. Minimum resistance should be added to maintain load and line transient
response.
Note: It is very important to check the selected manufacturers electrical characteristics (capacitance and ESR) over
temperature.
715xxS
CL
ESR
100
10
1
0.1
0 .01
0
50
100
IOUT (mA)
ESR (
)
STABLE
OPERATION
AREA
100
10
1
0.1
0 .01
0
50
100
IOUT (mA)
ESR (
)
STABLE
OPERATION
AREA
100
10
1
0.1
0 .01
0
50
100
IOUT (mA)
ESR (
)
STABLE
OPERATION
AREA
C
L
= 1.0
F
C
L
= 2.2
F
C
L
= 4.7
F
Note: It is not necessary to connect a ceramic capacitor
in parallel with an aluminum or tantalum output capacitor.
January 1999 TOKO, Inc.
Page 11
TK715xx
In general, the capacitor should be at least 1
F and be rated for the actual ambient operating temperature range. The
table below shows typical characteristics for several types and values of capacitance. Please note that the ESR varies
widely depending upon manufacturer, type, size, and material.
BOARD LAYOUT
Copper pattern should be as large as possible. Power dissipation is 350 mW for SOT-23-3. A low ESR capacitor is
recommended. For low temperature operation, select a capacitor with a low ESR at the lowest operating temperature
to prevent oscillation, degradation of ripple rejection and increase in noise. The minimum recommended capacitance is
2.2
F.
The internal reverse bias protection eliminates the requirement for a reverse voltage protection diode. This saves both
cost and board space.
SOT-23-3 BOARD LAYOUT
Note: ESR is measured at 10 kHz.
ESR
Capacitance
Aluminum
Capacitor
Tantalum
Capacitor
Ceramic
Capacitor
1.0
F
2.4
2.3
0.140
2.2
F
2.0
1.9
0.059
3.3
F
4.6
1.0
0.049
10
F
1.4
0.5
0.025
APPLICATION INFORMATION (CONT.)
+
+
VIN
VOUT
GND
Page 12
January 1999 TOKO, Inc.
TK715xx
REVERSE BIAS PROTECTION
The internal reverse bias protection eliminates the
requirement for a reverse voltage protection diode. This
saves both cost and board space.
Another reverse bias protection technique is illustrated
below. The extra diode and extra capacitor are not
necessary with the TK715xx. The high output voltage
accuracy is maintained because the diode forward voltage
variations over temperature and load current have been
eliminated.
PARALLEL OPERATION
The series resistor R is put in the input line of the low output
voltage regulator in order to prevent overdissipation. The
voltage dropped across the resistor reduces the large
input-to-output voltage across the regulator, reducing the
power dissipation in the device.
715xxS
VOUT
VIN
GND
APPLICATION INFORMATION (CONT.)
SWITCHING OPERATION
Even though the input voltages or the output voltages are
different, the outputs of the TK715xx regulators can be
connected together, and the output voltages switched. If
two or more TK715xx regulators are turned ON
simultaneously, the highest output voltage will be present.
CURRENT BOOST OPERATION
The output current can be increased by connecting an
external PNP transistor as shown below. The output
current capability depends upon the H
fe
of the external
transistor. Note: The TK715xx internal short circuit
protection and thermal sensor do not protect the external
transistor.
TK715xxS
VOUT
VIN
TK71550
5 V
VIN
TK71530
TK71520
3 V
2 V
R
TK715xx
VIN
VOUT
0.22 F
150
VIN
3.3 F
TK71530
VIN
TK71528
VIN
VOUT
3.0 OR 2.8 V
January 1999 TOKO, Inc.
Page 13
TK715xx
Marking Information
Product Code T
Voltage Code
TK71519S
19
TK71520S
20
TK71521S
21
TK71522S
22
TK71523S
23
TK71524S
24
TK71525S
25
TK71526S
26
TK71527S
27
TK71528S
28
TK71529S
29
TK71530S
30
TK71531S
31
TK71532S
32
TK71533S
33
TK71534S
34
TK71535S
35
TK71536S
36
TK71537S
37
TK71538S
38
TK71539S
39
TK71540S
40
TK71541S
41
TK71542S
42
TK71543S
43
TK71544S
44
TK71545S
45
TK71546S
46
TK71547S
47
TK71548S
48
TK71549S
49
TK71550S
50
TK71560S
60
TK71570S
70
TK71580S
80
TK71590S
90
Marking
Voltage Code
Product Code
2.9
Dimensions are shown in millimeters
Tolerance: x.x =
0.2 mm (unless otherwise specified)
1.4 max
0.1
1.1
0 - 0.1
(0.3)
2.8
+ 0.3
0.15
+ 0.1
1.6
(0.4)
15 max.
Recommended Mounting Pad
0.7
1.0
2.4
1.90
0.95
0.95
e1
e
e
e1
3
1
2
0.95
0.95
e
e
C1
0.1
0.4
+ 0.1
SOT-23-3
PACKAGE OUTLINE
Printed in the USA
1999 Toko, Inc.
All Rights Reserved
TOKO AMERICA REGIONAL OFFICES
Toko America, Inc. Headquarters
1250 Feehanville Drive, Mount Prospect, Illinois 60056
Tel: (847) 297-0070 Fax: (847) 699-7864
IC-xxx-TK715xx
0798O0.0K
Visit our Internet site at http://www.tokoam.com
The information furnished by TOKO, Inc. is believed to be accurate and reliable. However, TOKO reserves the right to make changes or improvements in the design, specification or manufacture of its
products without further notice. TOKO does not assume any liability arising from the application or use of any product or circuit described herein, nor for any infringements of patents or other rights of
third parties which may result from the use of its products. No license is granted by implication or otherwise under any patent or patent rights of TOKO, Inc.
Western Regional Office
Toko America, Inc.
2480 North First Street , Suite 260
San Jose, CA 95131
Tel: (408) 432-8281
Fax: (408) 943-9790
Midwest Regional Office
Toko America, Inc.
1250 Feehanville Drive
Mount Prospect, IL 60056
Tel: (847) 297-0070
Fax: (847) 699-7864
Eastern Regional Office
Toko America, Inc.
107 Mill Plain Road
Danbury, CT 06811
Tel: (203) 748-6871
Fax: (203) 797-1223
Semiconductor Technical Support
Toko Design Center
4755 Forge Road
Colorado Springs, CO 80907
Tel: (719) 528-2200
Fax: (719) 528-2375
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