March 2001 TOKO, Inc.
Page 1
TK715xxAS
BLOCK DIAGRAM
TK715xxAS
LOW DROPOUT VOLTAGE REGULATOR
The TK715xx is a low dropout linear regulator housed in a
small SOT23-3 package, rated at 400 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 60 dB ripple rejection and low noise
provide enhanced performance for critical applications.
DESCRIPTION
n
Battery Powered Systems
n
Cellular Telephones
n
Pagers
n
Personal Communications Equipment
n
Portable Instrumentation
n
Portable Consumer Equipment
n
Radio Control Systems
n
Toys
n
Low Voltage Systems
APPLICATIONS
n
High Voltage Precision at 2.0% or 60 mV
n
Very Low Quiescent Current
n
Very Low Dropout Voltage
n
Reverse Voltage Protection
n
Miniature Package (SOT23-3)
n
Short Circuit Protection
n
High Ripple Rejection
n
Can use Multilayer Ceramic Capacitors
FEATURES
GND
VOUT
VIN
20P
30T
TK715 ASCL
Voltage Code
Tape/ Reel Code
Temp. Code
Package Code
ORDERING INFORMATION
VOLTAGE CODE
15 = 1.5 V
35 = 3.5 V
16 = 1.6 V
36 = 3.6 V
17 = 1.7 V
37 = 3.7 V
18 = 1.8 V
38 = 3.8 V
19 = 1.9 V
39 = 3.9 V
20 = 2.0 V
40 = 4.0 V
21 = 2.1 V
41 = 4.1 V
22 = 2.2 V
42 = 4.2 V
23 = 2.3 V
43 = 4.3 V
24 = 2.4 V
44 = 4.4 V
25 = 2.5 V
45 = 4.5 V
26 = 2.6 V
46 = 4.6 V
27 = 2.7 V
47 = 4.7 V
28 = 2.8 V
48 = 4.8 V
29 = 2.9 V
49 = 4.9 V
30 = 3.0 V
50 = 5.0 V
31 = 3.1 V
60 = 6.0 V
32 = 3.2 V
70 = 7.0 V
33 = 3.3 V
80 = 8.0 V
34 = 3.4 V
90 = 9.0 V
TAPE/REEL CODE
L: Tape Left
TEMPERATURE CODE
C -30 to +80 C
PACKAGE CODE
S : SOT-23-3
GND
VIN
VOUT
THERMAL
PROTECTION
+
-
+
-
BANDGAP
REFERENCE
Page 2
March 2001 TOKO, Inc.
TK715xxAS
ABSOLUTE MAXIMUM RATINGS (V
OUT
5.0 V)
Supply Voltage ............................................. -0.4 to 19 V
Power Dissipation (Note 1) ................................ 400 mW
Reverse Bias ............................................................. 8 V
Short Circuit Current ........................................... 170 mA
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 18.0 V
Junction Temperature ......................................... 150 C
Lead Soldering Temperature (10 s) ..................... 235 C
TK715xx ELECTRICAL CHARACTERISTICS (V
OUT
5.0 V)
Test conditions: V
IN
= V
OUT(TYP)
+ 1V, T
A
= 25 C, unless otherwise specified.
Note 1: Power dissipation is 400 mW when mounted as recommended. Derate at 3.2 mW/C for operation above 25 C.
Note 2: Refer to "Definition of Terms."
Note 3: Please refer to the Applications Section for more information.
Note 4: Ripple rejection is measured at V
R
= 200 mVrms, V
IN
= V
OUT(TYP)
+ 2 V, I
OUT
= 10 mA, C
L
= 2.2 F, f = 100 Hz.
Note 5: The minimum operating voltage for V
IN
can be 1.8 V. Also, the minimum voltage required for V
IN
is V
IN
= V
DROP
+ V
OUT
. As a result, operating at
V
OUT
2.0 V at the minimum input operating voltage is not preferred.
Gen. Note: Parameters with min. or max. values are 100% tested at T
A
= 25 C.
L
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March 2001 TOKO, Inc.
Page 3
TK715xxAS
ABSOLUTE MAXIMUM RATINGS (V
OUT
5.1 V)
Supply Voltage ............................................. -0.4 to 19 V
Power Dissipation (Note 1) ................................ 400 mW
Reverse Bias ............................................................. 8 V
Short Circuit Current ........................................... 170 mA
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 18 V
Junction Temperature ......................................... 150 C
Lead Soldering Temperature (10 s) ..................... 235 C
TK715xx ELECTRICAL CHARACTERISTICS (V
OUT
5.1 V)
Test conditions: V
IN
= V
OUT(TYP)
+ 1V, T
A
= 25 C, unless otherwise specified.
Note 1: Power dissipation is 400 mW when mounted as recommended. Derate at 3.2 mW/C for operation above 25 C.
Note 2: Refer to "Definition of Terms."
Note 3: Ripple rejection is measured at V
R
= 200 mVrms, V
IN
= V
OUT(TYP)
+ 2 V, I
OUT
= 10 mA, C
L
= 2.2 F, f = 100 Hz.
Gen. Note: Parameters with min. or max. values are 100% tested at T
A
= 25 C.
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Page 4
March 2001 TOKO, Inc.
TK715xxAS
TK715xxAS ELECTRICAL CHARACTERISTICS TABLE 1
Output
Voltage
V
OUT(MIN)
V
OUT(MAX)
Test
Voltage
Code
Voltage
1.5 V
15
1.440 V
1.560 V
2.5 V
1.6 V
16
1.540 V
1.660 V
2.6 V
1.7 V
17
1.640 V
1.760 V
2.7 V
1.8 V
18
1.740 V
1.860 V
2.8 V
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
3.340 V
3.460 V
4.4 V
Output
Voltage
V
OUT(MIN)
V
OUT(MAX)
Test
Voltage
Code
Voltage
3.5 V
35
3.440 V
3.560 V
4.5 V
3.6 V
36
3.530 V
3.670 V
4.6 V
3.7 V
37
3.630 V
3.770 V
4.7 V
3.8 V
38
3.730 V
3.870 V
4.8 V
3.9 V
39
3.830 V
3.970 V
4.9 V
4.0 V
40
3.930 V
4.070 V
5.0 V
4.1 V
41
4.030 V
4.170 V
5.1 V
4.2 V
42
4.130 V
4.270 V
5.2 V
4.3 V
43
4.230 V
4.370 V
5.3 V
4.4 V
44
4.330 V
4.470 V
5.4 V
4.5 V
45
4.430 V
4.570 V
5.5 V
4.6 V
46
4.530 V
4.670 V
5.6 V
4.7 V
47
4.630 V
4.770 V
5.7 V
4.8 V
48
4.730 V
4.870 V
5.8 V
4.9 V
49
4.830 V
4.970 V
5.9 V
5.0 V
50
4.930 V
5.070 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
10.0 V
March 2001 TOKO, Inc.
Page 5
TK715xxAS
TYPICAL PERFORMANCE CHARACTERISTICS
T
A
= 25 C, unless otherwise specified.
TEST CIRCUIT
V
OUT
(10 m
V/ DIV)
LOAD REGULATION
IOUT (mA)
0 50 100
VOUT TYPICAL
V
OUT
(V)
3
5
SHORT CIRCUIT CURRENT
IOUT (mA)
1
0 100 200
4
2
0
V
OUT
(25 m
V/ DIV)
OUTPUT VOLTAGE vs.
INPUT VOLTAGE
VIN (V)
0
VOUT TYPICAL
IOUT = 100 mA
IOUT = 50 mA
IOUT = 0 mA
VIN = VOUT
50 mV/DIV
I REV
(
A
)
60
100
REVERSE BIAS CURRENT RANGE
VREV (V)
20
0 5 10
80
40
0
VOUT = 2.0 V
VOUT = 8.0 V
Because the output voltage is
different, the reverse current
will change this area.
(VIN = 0 V)
I Q
(m
A
)
2
INPUT CURRENT
VS.
INPUT VOLTAGE
VIN (V)
0 5 10
1
0
IOUT = 0 mA
VOUT = 3 V
V
OUT
(50 m
V/ DIV)
LINE REGULATION
VIN (V)
0 10 20
VOUT TYPICAL
IOUT
VIN
VIN
VOUT
CIN
0.1 F
VOUT
IIN
GND
CL
1.0 F
TANTALUM
Page 6
March 2001 TOKO, Inc.
TK715xxAS
TYPICAL PERFORMANCE CHARACTERISTICS (CONT.)
T
A
= 25 C, unless otherwise specified.
Ripple Rejection
V
DROP
(m
V)
-100
0
DROPOUT VOLTAGE
VS.
OUTPUT CURRENT
IOUT (mA)
-200
0 50 100
V
DROP
(m
V)
100
250
DROPOUT VOLTAGE
VS.
TEMPERATURE
TA(C)
50
-50 0 50 100
200
150
0
IOUT = 100 mA
IOUT = 50 mA
I GND
(
A)
200
500
GROUND PIN CURRENT vs.
OUTPUT CURRENT
IOUT (mA)
100
0 5 10 15
400
300
0
I GND
(m
A
)
2
5
GROUND PIN CURRENT vs.
OUTPUT CURRENT
IOUT (mA)
1
0 20 40 60 80 100
4
3
0
V
OUT
(m
V)
-10
OUTPUT VOLTAGE
VS.
TEMPERATURE
TA (C)
-20
-50 0 50 100
10
0
20
-30
3.0 V
I OUT
(m
A
)
120
180
MAX OUTPUT CURRENT
TA (C)
100
-50 0 50 100
160
140
0
3.0 V
CL
1.0 F
2.2 F
4.7 F
VOUT
VIN
0.1 F
GND
(TANTALUM OR CERAMIC)
715xxA
RIPPLE REJECTION CIRCUIT
dB
RIPPLE REJECTION
0.01 0.1 1 10 100 1000
-100
0
-90
-80
-70
-60
-50
-40
-30
-20
-10
F (kHz)
----TANTALUM
1.0
F : 4.7
F
CERAMIC
2.2
F : 4.7
F
IOUT = 10 mA
March 2001 TOKO, Inc.
Page 7
TK715xxAS
TYPICAL PERFORMANCE CHARACTERISTICS (CONT.)
T
A
= 25 C, unless otherwise specified.
Output Noise
Load & Line Response
CL
1.0 F
2.2 F
4.7 F
10 F
VOUT
VIN
0.1 F
GND
(TANTALUM)
715xxA
OUTPUT NOISE CIRCUIT
Note: To improve the load and line transient response, increase the value of the output capacitor.
NOISE (
V)
100
250
NOISE LEVEL (TK71530A)
VS.
OUTPUT CURRENT
IOUT (mA)
50
1.0 5.0 10
200
150
0
BW = 400 Hz~80 KHz
CL = 10
F
CL = 4.7
F
CL = 2.2
F
CL = 1
F
LINE VOLTAGE STEP RESPONSE
I
OUT
= 10mA
VIN
VOUT
VOUT + 2V
VOUT + 1V
50 mV/DIV
CL = 1.0
F
25
S/DIV
LOAD CURRENT
STEP RESPONSE
IOUT
VOUT
50 mA
50 mV/DIV
5 mA
CL = 1.0
F
25
S/DIV
Page 8
March 2001 TOKO, Inc.
TK715xxAS
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
= 5 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 tempera-
ture.
CONTINUOUS OUTPUT CURRENT (I
OUT
)
Normal operating output current. This is limited by pack-
age power dissipation.
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 18 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 the output current step con-
dition 5 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 2.2 F and the load current
is set to 10 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 re-
mains 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 de-
signed 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 af-
fected 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 SOT23-3 is increased to 400 mW. For operation at
ambient temperatures over 25 C, the power dissipation of
the SOT23-3 device should be derated at 3.2 mW/C. To
March 2001 TOKO, Inc.
Page 9
TK715xxAS
DEFINITION AND EXPLANATION OF TECHNICAL TERMS (CONT.)
determine the power dissipation for shutdown when
mounted, attach the device on the actual PCB and delib-
erately increase the output current (or raise the input
voltage) until the thermal protection circuit is activated.
Calculate the power dissipation of the device by subtract-
ing the output power from the input power. These mea-
surements 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
)
SOT23-3 POWER DISSIPATION CURVE
PD
DPD
25
50
75
150
(mW)
TA (
C)
3
6
5
4
0 50 100 150
TA (C)
P
D
(m
W)
0
300
500
100
200
400
MOUNTED AS SHOWN
FREE AIR
Page 10
March 2001 TOKO, Inc.
TK715xxAS
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. The output capacitor C
L
can be reduced as the output voltage is increased. However, the output noise will
increase as C
L
is reduced, so the largest value of C
L
possilbe is recommended (C
L
= 4.7
m
F or more).
Note: It is very important to check the selected manufacturers electrical characteristics (capacitance and ESR) over
temperature.
Range which can be used:
Range which can be used: V
OUT
1.9V I
OUT
= 1 mA ~ Max, TANTALUM CAP.
0.1
m
F (CERAMIC CAP 0.22
m
F
+ 2.2
W
Capacitor used for evaluation: V
OUT
1.5V I
OUT
= 1 mA ~ Max, TANTALUM CAP.
0.22
m
F (CERAMIC CAP 0.22
m
F + 2.2
W
V
OUT
2.8V I
OUT
= 1 mA ~ Max, MULTI LAYER CERAMIC CAP.
0.68
m
F
V
OUT
2.0V I
OUT
= 1 mA ~ Max, MULTI LAYER CERAMIC CAP.
1.0
m
F
V
OUT
1.5V I
OUT
= 1 mA ~ Max, MULTI LAYER CERAMIC CAP.
4.7
m
F
ESR
0.01
0.68
F
CL
4.7
F or More
ESR
1.0
0.1
F
CL
0.22
F or More
MULTI LAYER CERAMIC CAP
I
OUT
(mA)
5.0
1.6
1.5
1.8
2.0
2.2
2.4
2.6
2.8
3.0
3.2
3.4
3.6
3.8
0 20 40 60 80 100
CL = 4.7
F MLCC or More
CL = 0.68
F MLCC
C
IN
= 0.1
F
Stable area is
above the line
UNSTABLE AREA UNDER
AND TO THE LEFT
3.3
F
2.2
F
1.0
F
TANTALUM CAP
I
OUT
(mA)
5.0
1.6
1.5
1.8
2.0
2.2
2.4
2.6
2.8
3.0
3.2
3.4
3.6
3.8
0 20 40 60 80 100
V
OUT
(V)
Stable area is
above the line
UNSTABLE AREA UNDER
AND TO THE LEFT
CL = 0.22
F (TANTALUM) or More
CL = 0.1
F TANTALUM
0.1
F
CIN = 0.1
F
March 2001 TOKO, Inc.
Page 11
TK715xxAS
APPLICATION INFORMATION (CONT)
INPUT-OUTPUT CAPACITORS (CONT)
OUTPUT NOISE IMPROVEMENT
An RC filter can be added to the output stage of the regulator to reduce output noise when the input voltage is high and
the output current only makes small changes. Select a regulator with a slightly higher output voltage because the final
output voltage will be reduced by the RC filter. If the output current does make a large change, the output voltage will
change. The following table shows output noise, and output voltage for various values of R
OUT
and C
OUT
using a 3.5 V
device.
V
IN
= 4.0 V, C
IN
= 10
m
F (aluminum electrolytic), C
OUT
= (see table), R
OUT
= (see table)
RIPPLE REJECTION RATIO
An RC filter can be added to the input stage of the regulator to increase the ripple rejection when the input voltage is high.
Even if the resulting difference between V
IN
at the regulator (after the RC filter) and V
OUT
is small the TK71533AS will
output a stable voltage. The voltage dropped across the RC filter depends on the value of the input ripple noise. Select
the value of R
IN
such that the lowest value of V
IN
plus the ripple noise after the RC filter (peak to peak) is the output voltage
plus 0.2 V.
N
O
I
T
I
D
N
O
C
T
N
E
M
E
R
U
S
A
E
M
C
(
R
O
T
I
C
A
P
A
C
E
D
I
S
T
U
P
T
U
O
T
U
O
)
S
T
I
N
U
I
T
U
O
R
T
U
O
V
T
U
O
F
0
1
F
7
4
F
0
0
1
F
C
T
U
O
I
T
U
O
A
m
0
4
-
0
2
=
0
V
0
0
5
.
3
V
0
1
2
V
0
5
1
V
0
3
1
S
M
R
E
S
I
O
N
A
m
0
2
0
1
W
V
6
9
2
.
3
V
6
7
V
0
5
V
0
4
S
M
R
A
m
0
3
8
.
6
W
V
7
8
2
.
3
V
8
8
V
5
5
V
8
4
S
M
R
A
m
0
4
1
.
5
W
V
6
6
2
.
3
V
0
0
1
V
0
6
V
8
4
S
M
R
TK715xxA
VOUT
COUT
VIN
CL = 2.2 F
LOAD ADJ.
IOUT = 20, 30, 40 mA
ROUT
TK715xxA
VOUT
CL
CIN
VIN
LOAD ADJ.
IOUT = 20, 30, 40 mA
RIN
Page 12
March 2001 TOKO, Inc.
TK715xxAS
In general, a ceramic capacitor has a voltage and temperature dependence. Parts should be selected with consideration
of the voltage and temperature used. The "B" characteristic curves are recommended.
APPLICATION INFORMATION (CONT)
VOLTAGE DEPENDENCY
100
90
80
70
60
50
40
CA
PA
CITA
NCE (%)
0 2 4 6 8 10
F CURVE
B CURVE
BIAS V (V)
TEMPERATURE DEPENDENCY
100
90
80
70
60
50
CA
PA
CITA
NCE (%)
-50 -25 0 25 50 75 100
F CURVE
B CURVE
TA (C)
R(*) MAG -17.98 dB 10 dB/ -50.00 dB
B(*) B -41.05 dB 10 dB/ -50.00 dB
START: 100 Hz STOP: 1 MHz
OUT (B): -20.00 dBm ST: AUTO x1 1 M
IRG: 26 dBm RBW: 30 kHZ VBW: 38 kHz
FILTER
RIN = 27
CIN = 47
F
R(*) MAG -57.78 dB 10 dB/ -50.00 dB
B(*) B -41.05 dB 10 dB/ -50.00 dB
START: 100 Hz STOP: 1 MHz
OUT (B): -20.00 dBm ST: AUTO x1 1 M
IRG: 26 dBm RBW: 30 kHZ VBW: 38 kHz
FILTER + TK71533
RIN = 27
CIN = 47
F CL = 10
F
TK71533
March 2001 TOKO, Inc.
Page 13
TK715xxAS
BOARD LAYOUT
The copper pattern should be as large as possible. Power dissipation is 400 mW for the SOT23-3, derated at 3.2 mW/C for
operation above T
A
= 25C (
q
ja = 312C/W)
The internal reverse bias protection eliminates the requirement for a reverse voltage protection diode. This saves both
cost and board space.
APPLICATION INFORMATION (CONT.)
SOT23-3 BOARD LAYOUT
+
+
VIN
VOUT
GND
RECOMMENDED AS SHOWN
FREE AIR
500
400
300
200
100
P
D(
m
W
)
Page 14
March 2001 TOKO, Inc.
TK715xxAS
REVERSE VOLTAGE PROTECTION
The internal reverse bias protection eliminates the require-
ment for a reverse voltage protection diode. This saves
both cost and board space.
Another reverse voltage protection technique is illustrated
below. The extra diode and extra capacitor are not neces-
sary with the TK715xxA. The high output voltage accuracy
is maintained because the diode forward voltage varia-
tions over temperature and load current have been elimi-
nated.
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.
APPLICATION INFORMATION (CONT.)
SWITCHING OPERATION
Even though the input voltages or the output voltages are
different, the outputs of the TK715xxA regulators can be
connected together, and the output voltages switched. If
two or more TK715xxA regulators are turned ON simulta-
neously, 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 TK715xxA internal short circuit pro-
tection and thermal sensor do not protect the external
transistor.
715xxAS
VOUT
VIN
GND
TK715xxAS
VOUT
VIN
TK71550A
5 V
VIN
TK71530A
TK71520A
3 V
2 V
R
TK715xxA
VIN
VOUT
0.22 F
150
VIN
3.3 F
TK71530A
VIN
TK71528A
VIN
VOUT
3.0 OR 2.8 V
March 2001 TOKO, Inc.
Page 15
TK715xxAS
Marking Information
Product Code T Voltage Code
TK71515S
15
TK71516S
16
TK71517S
17
TK71518S
18
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
SOT23-3
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
Semiconductor Technical Support
Toko Design Center
4755 Forge Road
Colorado Springs, CO 80907
Tel: (719) 528-2200
Fax: (719) 528-2375
3
1
2
Marking
2.9
Dimensions are shown in millimeters
Tolerance: x.x = 0.2 mm (unless otherwise specified)
1.3 m
a
x
1.1
0 ~ 0.1
2.8
0.15
1.6
0.4
Recommended Mounting Pad
0.8
1.0
2.4
0.95
0.95
e
e
e1
0.95
0.95
e
e
C1
0.1
0.4
+ 0.15
0.05
+ 0.15
0.05
0.1
VOLTAGE CODE
PRODUCT CODE
0.1
15
ma
x
0.3
e1 1.90
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