TS2940
Taiwan Semiconductor
1A Ultra Low Dropout Voltage Regulator
GENERAL DESCRIPTION
The TS2940 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 low drop output voltage (Typ. 60mV at light
load and 600mV at 800mA). This includes a tight initial
tolerance of 2%, extremely good line regulation of
0.05% typ., and very low output temperature coefficient.
FEATURES
●
●
●
●
●
●
●
●
Dropout voltage typically 0.6V @ Io=800mA
Output current up to 1A
Output voltage trimmed before assembly
-18V Reverse peak voltage
+30V Input over voltage protection
+60V Transient peak voltage
Internal current limit
Thermal shutdown protection
APPLICATION
●
●
Post Regulator for SMPS
Industrial Instrumentation
TO-220
TO-263 (D PAK)
2
TO-252 (DPAK)
SOT-223
Pin Definition:
1. Input
2. Ground
3. Output
Notes:
Moisture sensitivity level: level 3. Per J-STD-020
TYPICAL APPLICATION CIRCUIT
Document Number: DS_P0000211
1
Version: D15
TS2940
Taiwan Semiconductor
ABSOLUTE MAXIMUM RATINGS
(T
A
= 25°C unless otherwise noted)
PARAMETER
Input Supply Voltage
Input Supply Voltage
Power Dissipation
(Note 3)
(Note 2)
SYMBOL
V
IN
V
OPR
P
D
T
J
T
STG
LIMIT
-18 ~ +60
26
Internally Limited
-40 ~ +125
-65 ~ +150
UNIT
V
V
W
°C
°C
Operating Junction Temperature Range
Storage Temperature Range
THERMAL PERFORMANCE
PARAMETER
Thermal Resistance
Junction to Ambient
PACKAGE TYPE
TO-220
TO-263
TO-252
SOT-223
R
ӨJA
SYMBOL
LIMIT
60
80
150
170
°C/W
UNIT
Notes:
R
ӨJA
is the sum of the junction-to-case and case-to-ambient thermal resistances. The case thermal reference is defined
at the solder mounting surface of the drain pins. R
ӨJA
is guaranteed by design while R
ӨCA
is determined by the user’s board
design. R
ӨJA
shown below for single device operation on FR-4 PCB in still air.
ELECTRICAL SPECIFICATIONS
(V
IN
=V
OUT
+1V, I
L
=5mA, C
O
=22µF, T
A
=25°C, unless otherwise noted)
PARAMETER
Input Supply Voltage
Output Voltage
Output Voltage Temperature
Coefficient
Line Regulation
Load Regulation
Dropout Voltage
(Note 4)
CONDITIONS
5mA
≤
I
L
≤
800mA,
Vo+5V
≤
V
IN
≤
26V
MIN
--
0.970|Vo|
--
TYP
--
5.0
3.3
50
0.05
0.2
100
300
600
10
75
--
500
350
120
MAX
26
1.030|Vo|
150
0.5
1.0
200
500
800
15
110
1.5
--
--
--
UNIT
V
V
ppm/°C
%
%
mV
Vo+2V
≤
V
IN
≤
26V
5mA
≤
I
L
≤
800mA
I
L
=100mA
I
L
=500mA
I
L
=800mA
I
L
=5mA
I
L
=800mA
(Note 6)
--
--
--
--
--
--
--
--
--
--
--
Quiescent Current
(Note 5)
mA
A
µVrms
Short Circuit Current
Output Noise,
V
OUT
=0
C
L
=2.2µF
C
L
=3.3µF
C
L
=33µF
10Hz to 100KHz, I
L
=10mA
Document Number: DS_P0000211
2
Version: D15
TS2940
Taiwan Semiconductor
ELECTRICAL SPECIFICATIONS
Note:
1.
2.
3.
Absolute Maximum Rating is limits beyond which damage to the device may occur. For guaranteed specifications and test
conditions see the electrical characteristics.
Maximum positive supply voltage of 60V must be limited duration (<100ms) and duty cycle (<1%).
The maximum allowable power dissipation is a function of the maximum junction temperature, T
J
, the junction to ambient
thermal resistance, R
ӨJA
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 R
ӨJA
can be reduced by
using a heatsink.
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.
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.
Output current will decrease with increasing temperature, but it will be not dropped below 1A at the maximum specified
temperature.
4.
5.
6.
ORDERING INFORMATION
OUTPUT VOLTAGE
3.3V
3.3V
3.3V
3.3V
5.0V
5.0V
5.0V
5.0V
PART NO.
TS2940CZ33 C0G
TS2940CM33 RNG
TS2940CP33 ROG
TS2940CW33 RPG
TS2940CZ50 C0G
TS2940CM50 RNG
TS2940CP50 ROG
TS2940CW50 RPG
PACKAGE
TO-220
TO-263
TO-252
SOT-223
TO-220
TO-263
TO-252
SOT-223
PACKING
50pcs / Tube
800pcs / 13” Reel
2,500pcs / 13” Reel
2,500pcs / 13” Reel
50pcs / Tube
800pcs / 13” Reel
2,500pcs / 13” Reel
2,500pcs / 13” Reel
Note:
1. Compliant to RoHS Directive 2011/65/EU and in accordance to WEEE 2002/96/EC.
2. Halogen-free according to IEC 61249-2-21 definition.
Document Number: DS_P0000211
3
Version: D15
TS2940
Taiwan Semiconductor
BLOCK DIAGRAM
APPLICATION INFORMATION
The TS2940 series is a high performance with low dropout voltage regulator suitable for moderate to high current
and voltage regulator application. Its 600mA (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 TS2940 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.
Output Capacitor
The TS2940 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 22µF 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 TS2940 series is specified between finite loads. If the output current is too small leakage currents dominate
and the output voltage rises. A 10mA minimum load current is necessary for proper regulation.
Input Capacitor
An input capacitor of 1µF 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.
Document Number: DS_P0000211
4
Version: D15
TS2940
Taiwan Semiconductor
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, P
D
must be calculated.
The below formula shows the voltages and currents for calculating the P
D
in the regulator:
IIN = IL / IG
P
D
= (V
IN
-V
OUT
) * I
L
+ (V
IN
) * I
G
Ex. P
D
= (3.3V-2.5V) * 1A + 3.3V * 11mA
= 800mW + 36mW
= 836mW
Remark: I
L
is output load current,
I
G
is ground current.
V
IN
is input voltage
V
OUT
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 125°C for commercial grade parts.
T
A
(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:
R
ӨJA
= TR(max) / PD
IMPORTANT: if the maximum allowable value for is found to be
≥60°C
/W for the TO-220 package,
≥80
C/W for
the TO-263 package,
≥150°C/W
for the TO-252 package, or
≥170°C
/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
R
ӨJA
falls below these limits, a heatsink is required.
o
Document Number: DS_P0000211
5
Version: D15
京公网安备 11010802033920号
EEWORLD
