TS4274
400mA Ultra Low Dropout Fixed Voltage Regulator
1/10 Version: A07
TO-220
TO-263
(D2PAK)
TO-252
(DPAK)
SOT-223
General Description
The TS4274 series of fixed-voltage monolithic micro-power voltage regulators is designed for a wide range of
applications. This device excellent choice of use in battery-power application. Furthermore, the quiescent current
increases on slightly at dropout, which prolongs battery life.
This series of fixed-voltage regulators features very low ground current (200uA Typ.) and very low drop output voltage
(600mV at 400mA). This includes a tight initial tolerance of 2% typ., and very low output temperature coefficient.
Features
● Dropout voltage typically 0.6V @Io=400mA
● Output current up to 400mA
● Output voltage trimmed before assembly
● Load dump protection
● Internal current limit
● Thermal shutdown protection
Block Diagram
Ordering Information
Note: Where xx denotes voltage option, available are
12= 12V
50= 5.0V
33= 3.3V
25= 2.5V
18= 1.8V
Package
Packing
TO-220
50pcs / Tube
TO-263
800pcs / 13” Reel
TO-252
2.5Kpcs / 13” Reel
SOT-223
2.5Kpcs / 13” Reel
Absolute Maximum Rating
Parameter
Symbol
Limit
Unit
Input Supply Voltage
VIN
-18 ~ +35
V
Operation Input Supply Voltage
VOPR
26
V
Power Dissipation
PD
Internally Limited
W
Junction Temperature Range
TJ
+150
oC
Operating Temperature Range
TOPR
-40 ~ + 85
oC
Storage Temperature Range
TSTG
-65 ~ +150
oC
Pin Definition:
1. Input
2. Ground
3. Output
TS4274
400mA Ultra Low Dropout Fixed Voltage Regulator
2/10 Version: A07
Electrical Characteristics ( VIN=VOUT+1V, IL=5mA, CO=10uF, TA=25oC, unless otherwise noted)
Parameter
Conditions
Min
Typ
Max
Unit
2.40
2.5
2.60
3.17
3.3
3.43
Output Voltage
5mA ≤ IL ≤ 500mA,
Vo+1V ≤ VIN ≤ 26V
4.80
5.0
5.20
V
Input Supply Voltage
--
--
26
V
Output Voltage Temperature Coefficient
--
50
150
ppm/ oC
Line Regulation
Vo+1V ≤ VIN ≤ 26V
--
0.05
0.5
%
Load Regulation
5mA ≤ IL ≤ 400mA
--
0.2
2.0
%
Dropout Voltage (Note 4)
IL=100mA
IL=250mA
IL=400mA
--
--
--
100
300
500
200
400
600
mV
Quiescent Current (Note 5)
IL=100uA
IL=250mA
IL=400mA
--
--
--
200
10
25
300
15
35
uA
mA
mA
Short Circuit Current (Note 6)
VOUT=0
--
600
900
mA
Output Noise,
10Hz to 100KHz, IL=10mA
CL=2.2uF
CL=3.3uF
CL=33uF
--
--
--
500
350
120
--
--
--
uVrms
Power Supply Ripple Rejection
F=100Hz, Vr=0.5Vss
--
60
--
dB
Thermal Performance
Condition
Package type
Typ
Unit
TO-220
60
TO-263
80
TO-252
150
Thermal Resistance
Junction to Ambient
SOT-223
170
oC/W
Note 1: Absolute Maximum Rating is limits beyond which damage to the device may occur. For guaranteed
specifications and test conditions see the electrical characteristics.
Note 2: Maximum positive supply voltage of 35V must be limited duration (<100mS) and duty cycle (<1%).
Note 3: The maximum allowable power dissipation is a function of the maximum junction temperature, TJ, the junction
to ambient thermal resistance, θJA, and the ambient temperature, Ta. Exceeding the maximum allowable
power dissipation will cause excessive die temperature, and the regulator will go into thermal shutdown. The
effective value of θJA can be reduced by using a heatsink.
Note 3: Dropout voltage is defined as the input to output differential at which the output voltage drops 2% below its
nominal value measured at 1V differential.
Note 4: Ground pin current is the regulator quiescent current. The total current drawn from the source is the sum of the
ground pin current and output load current.
Note 5: Output current will decrease with increasing temperature, but it will be not dropped below 400mA at the
maximum specified temperature.
TS4274
400mA Ultra Low Dropout Fixed Voltage Regulator
3/10 Version: A07
Application Information
The TS4274 series is a high performance with low dropout voltage regulator suitable for moderate to high current and
voltage regulator application. Its 600mV(typ) dropout voltage at full load and over temperature makes it especially
valuable in battery power systems and as high efficiency noise filters in post regulator applications. Unlike normal NPN
transistor design, where the base to emitter voltage drop and collector to emitter saturation voltage limit the minimum
dropout voltage, dropout performance of the PNP output of these devices is limited only by low Vce saturation voltage.
The TS4274 series is fully protected from damage due to fault conditions. Linear current limiting is provided. Output
current during overload conditions is constant. Thermal shutdown the device when the die temperature exceeds the
maximum safe operating temperature. Transient protection allows device survival even when the input voltage spikes
above and below nominal. The output structure of these regulators allows voltages in excess of the desired output
voltage to be applied without reverse current flow.
Typical Application Circuit
Output Capacitor
The TS4274 series requires an output capacitor to maintain stability and improve transient response. Proper capacitor
selection is important to ensure proper operation. The output capacitor selection is dependent upon the ESR of the
output capacitor the maintain stability. When the output capacitor is 10uF or greater, the output capacitor should have
an ESR less than 2 ohm. This will improve transient response as well as promoted stability. Ultra low ESR capacitors
(<100mohm), such as ceramic chip capacitors may promote instability. These very low ESR levels may cause an
oscillation and/or under damped transient response. A low ESR solid tantalum capacitor works extremely well and
provides good transient response and stability over temperature. Aluminum electrolytic can also be used, as long as
the ESR of the capacitor is <2ohm. The value of the output capacitor can be increased without limit. Higher
capacitance values help to improved transient response and ripple rejection and reduce output noise.
Minimum Load Current
The TS4274 series is specified between finite loads. If the output current is too small leakage currents dominate and
the output voltage rises. A 1mA minimum load current is necessary for proper regulation.
Input Capacitor
An input capacitor of 1uF or greater is recommended when the device is more that 4 inches away from the bulk AC
supply capacitance or when the supply is a battery. Small and surface mount ceramic chip capacitors can be used for
bypassing. Larger values will help to improve ripple rejection by bypassing the input to the regulator, further improving
the integrity of the output voltage.
TS4274
400mA Ultra Low Dropout Fixed Voltage Regulator
4/10 Version: A07
Application Information (Continue)
Thermal Characteristics
A heatsink may be required depending on the maximum power dissipation and maximum ambient temperature of the
application. Under all possible operating conditions, the junction temperature must be within the range specified under
absolute maximum ratings. To determine if the heatsink is required, the power dissipated by the regulator, PD must be
calculated.
The below formula shows the voltages and currents for calculating the PD in the regulator:
IIN = IL / IG
PD = (VIN-VOUT) * IL + (VIN) * IG
Ex. PD = (3.3V-2.5V) * 0.5A + 3.3V * 11mA
= 400mW + 36mW
= 436mW
Remark: IL is output load current,
IG is ground current.
VIN is input voltage
VOUT is output voltage
The next parameter which must be calculated is the maximum allowable temperature rise.
TR(max) is calculated by the using to formula:
TR(max) = TJ(max) – TA(max)
Where: TJ(max) is the maximum allowable junction temperature, which is 125oC for commercial grade parts. TA(max)
is the maximum ambient temperature which will be encountered in the application.
Using the calculated values for TR(max) and PD, the maximum allowable value for the junction to ambient thermal
resistance, θJA, can now be found:
θJA = TR(max) / PD
IMPORTANT: if the maximum allowable value for is found to be ≥60oC /W for the TO-220 package, ≥80oC/W for the
TO-263 package, ≥150oC/W for the TO-252 package, or ≥170oC /W for the SOT-223 package, no heatsink is needed
since the package alone will dissipate enough heat to satisfy these requirements. If the calculated value for θJA falls
below these limits, a heatsink is required.
TS4274
400mA Ultra Low Dropout Fixed Voltage Regulator
5/10 Version: A07
Application Information (Continue)
Figure 1 – D2PAK Thermal Resistance and Maximum Power
Dissipation vs. P.C.B Copper Length
Figure 2 – DPAK Thermal Resistance and Maximum Power
Dissipation vs. P.C.B Copper Length
Figure 3 – SOT-223 Thermal Resistance and Maximum Power
Dissipation vs. P.C.B Copper Length
TS4274
400mA Ultra Low Dropout Fixed Voltage Regulator
6/10 Version: A07
TO-220 Mechanical Drawing
Marking Diagram
Y
= Year Code
M
= Month Code
(A=Jan, B=Feb, C=Mar, D=Apl, E=May, F=Jun, G=Jul, H=Aug, I=Sep,
J=Oct, K=Nov, L=Dec)
L
= Lot Code
XX
= Voltage Code
(1.8=1.8V, 2.5=2.5V, 3.3=3.3V, 5.0=5V, 12=12V)
TO-220 DIMENSION
MILLIMETERS
INCHES
DIM
MIN
MAX
MIN
MAX
A
10.000
10.500
0.394
0.413
B
3.740
3.910
0.147
0.154
C
2.440
2.940
0.096
0.116
D
-
6.350
-
0.250
E
0.381
1.106
0.015
0.040
F
2.345
2.715
0.092
0.058
G
4.690
5.430
0.092
0.107
H
12.700
14.732
0.500
0.581
I
8.382
9.017
0.330
0.355
J
14.224
16.510
0.560
0.650
K
3.556
4.826
0.140
0.190
L
0.508
1.397
0.020
0.055
M
27.700
29.620
1.060
1.230
N
2.032
2.921
0.080
0.115
O
0.255
0.610
0.010
0.024
P
5.842
6.858
0.230
0.270
TS4274
400mA Ultra Low Dropout Fixed Voltage Regulator
7/10 Version: A07
TO-263 Mechanical Drawing
Marking Diagram
Y
= Year Code
M
= Month Code
(A=Jan, B=Feb, C=Mar, D=Apl, E=May, F=Jun, G=Jul, H=Aug, I=Sep,
J=Oct, K=Nov, L=Dec)
L
= Lot Code
XX
= Voltage Code
(1.8=1.8V, 2.5=2.5V, 3.3=3.3V, 5.0=5V, 12=12V)
TO-263 DIMENSION
MILLIMETERS
INCHES
DIM
MIN
MAX
MIN
MAX
A
10.000
10.500
0.394
0.413
B
14.605
15.875
0.575
0.625
C
0.508
0.991
0.020
0.039
D
2.420
2.660
0.095
0.105
E
4.064
4.830
0.160
0.190
F
1.118
1.400
0.045
0.055
G
0.450
0.730
0.018
0.029
H
8.280
8.800
0.325
0.346
I
1.140
1.400
0.044
0.055
J
1.480
1.520
0.058
0.060
TS4274
400mA Ultra Low Dropout Fixed Voltage Regulator
8/10 Version: A07
TO-252 Mechanical Drawing
Marking Diagram
Y
= Year Code
M
= Month Code
(A=Jan, B=Feb, C=Mar, D=Apl, E=May, F=Jun, G=Jul, H=Aug, I=Sep,
J=Oct, K=Nov, L=Dec)
L
= Lot Code
XX
= Voltage Code
(1.8=1.8V, 2.5=2.5V, 3.3=3.3V, 5.0=5V, 12=12V)
TO-252 DIMENSION
INCHES
DIM
MIN
MAX
MIN
MAX
A
0.09BSC
A1
0.18BSC
B
6.80
7.20
0.268
0.283
C
5.40
5.60
0.213
0.220
D
6.40
6.65
0.252
0.262
E
2.20
2.40
0.087
0.094
F
0.00
0.20
0.000
0.008
G
5.20
5.40
0.205
0.213
G1
0.75
0.85
0.030
0.033
G2
0.55
0.65
0.022
0.026
H
0.35
0.65
0.014
0.026
I
0.90
1.50
0.035
0.059
J
2.20
2.80
0.087
0.110
K
0.50
1.10
0.020
0.043
L
0.90
1.50
0.035
0.059
M
1.30
1.70
0.051
0.67
TS4274
400mA Ultra Low Dropout Fixed Voltage Regulator
9/10 Version: A07
SOT-223 Mechanical Drawing
Marking Diagram
Y
= Year Code
M
= Month Code
(A=Jan, B=Feb, C=Mar, D=Apl, E=May, F=Jun, G=Jul, H=Aug, I=Sep,
J=Oct, K=Nov, L=Dec)
L
= Lot Code
XX
= Voltage Code
(1.8=1.8V, 2.5=2.5V, 3.3=3.3V, 5.0=5V, 12=12V)
SOT-223 DIMENSION
MILLIMETERS
INCHES
DIM
MIN
MAX
MIN
MAX
A
6.350
6.850
0.250
0.270
B
2.900
3.100
0.114
0.122
C
3.450
3.750
0.136
0.148
D
0.595
0.635
0.023
0.025
E
4.550
4.650
0.179
0.183
F
2.250
2.350
0.088
0.093
G
0.835
1.035
0.032
0.041
H
6.700
7.300
0.263
0.287
I
0.250
0.355
0.010
0.014
J
10°
16°
10°
16°
K
1.550
1.800
0.061
0.071
TS4274
400mA Ultra Low Dropout Fixed Voltage Regulator
10/10 Version: A07
Notice
Specifications of the products displayed herein are subject to change without notice. TSC or anyone on its behalf,
assumes no responsibility or liability for any errors or inaccuracies.
Information contained herein is intended to provide a product description only. No license, express or implied, to any
intellectual property rights is granted by this document. Except as provided in TSC’s terms and conditions of sale for
such products, TSC assumes no liability whatsoever, and disclaims any express or implied warranty, relating to sale
and/or use of TSC products including liability or warranties relating to fitness for a particular purpose, merchantability,
or infringement of any patent, copyright, or other intellectual property right.
The products shown herein are not designed for use in medical, life-saving, or life-sustaining applications. Customers
using or selling these products for use in such applications do so at their own risk and agree to fully indemnify TSC for
any damages resulting from such improper use or sale.