TI TPS61040DBVR

TPS61040
TPS61041
www.ti.com
SLVS413C – OCTOBER 2002 – REVISED AUGUST 2007
LOW-POWER DC/DC BOOST CONVERTER IN SOT-23 AND SON PACKAGES
FEATURES
DESCRIPTION
1
•
•
•
•
•
•
•
•
1.8-V to 6-V Input Voltage Range
Adjustable Output Voltage Range up to 28 V
400-mA (TPS61040) and 250-mA (TPS61041)
Internal Switch Current
Up to 1-MHz Switching Frequency
28-μA Typical No-Load Quiescent Current
1-μA Typical Shutdown Current
Internal Soft Start
Available in SOT23-5 and 2 × 2 × 0.8-mm SON
Packages
The TPS61040/41 is a high-frequency boost
converter dedicated for small to medium LCD bias
supply and white LED backlight supplies. The device
is ideal to generate output voltages up to 28 V from a
dual cell NiMH/NiCd or a single cell Li-Ion battery.
The part can also be used to generate standard
3.3-V/5-V to 12-V power conversions.
The TPS61040/41 operates with a switching
frequency up to 1 MHz. This allows the use of small
external components using ceramic as well as
tantalum output capacitors. Together with the thin
SON package, the TPS61040/41 gives a very small
overall solution size. The TPS61040 has an internal
400 mA switch current limit, while the TPS61041 has
a 250-mA switch current limit, offering lower output
voltage ripple and allows the use of a smaller form
factor inductor for lower power applications. The low
quiescent current (typically 28 μA) together with an
optimized control scheme, allows device operation at
very high efficiencies over the entire load current
range.
APPLICATIONS
•
•
•
•
•
•
•
LCD Bias Supply
White-LED Supply for LCD Backlights
Digital Still Camera
PDAs, Organizers, and Handheld PCs
Cellular Phones
Internet Audio Player
Standard 3.3-V/5-V to 12-V Conversion
DBV PACKAGE
(Top View)
SW
1
GND
2
FB
3
5
DRV PACKAGE
(Top View)
VIN
4
EN
GND
1
6
SW
VIN
2
5
NC
EN
3
4
FB
TYPICAL APPLICATION
EFFICIENCY
vs
OUTPUT CURRENT
5 V
IN
SW
FB
D1
R1
1
VI = 5 V
86
84
CFF
CO
1 µF
3
VO = 18 V
88
VOUT
VIN to 28 V
Efficiency - %
VIN
1.8 V to 6.0 V
CIN
4.7 µF
90
L1
10 µH
VI = 3.6 V
82
80
VI = 2.4 V
78
76
4
EN
GND
2
R2
74
72
70
0.10
1
10
IO - Output Current - mA
100
1
Please be aware that an important notice concerning availability, standard warranty, and use in critical applications of
Texas Instruments semiconductor products and disclaimers thereto appears at the end of this data sheet.
PRODUCTION DATA information is current as of publication date.
Products conform to specifications per the terms of the Texas
Instruments standard warranty. Production processing does not
necessarily include testing of all parameters.
Copyright © 2002–2007, Texas Instruments Incorporated
TPS61040
TPS61041
www.ti.com
SLVS413C – OCTOBER 2002 – REVISED AUGUST 2007
These devices have limited built-in ESD protection. The leads should be shorted together or the device placed in conductive foam
during storage or handling to prevent electrostatic damage to the MOS gates.
ORDERING INFORMATION
TA
–40°C to
85°C
(1)
(1)
PART NUMBER
SWITCH CURRENT
LIMIT, mA
PACKAGE
PACKAGE
MARKING
TPS61040DBV
400
SOT23-5
PHOI
TPS61041DBV
250
SOT23-5
PHPI
TPS61040DRV
400
SON-6 2×2
CCL
TPS61041DRV
250
SON-6 2×2
CAW
The devices are available in tape and reel and in tubes. Add R suffix to the part number (e.g.,
TPS61040DRVR) to order quantities of 3000 parts in tape and reel or add suffix T (e.g.,
TPS61040DRVT) to order a tube with 250 pieces..
FUNCTIONAL BLOCK DIAGRAM
SW
Under Voltage
Lockout
Bias Supply
VIN
400 ns Min
Off Time
Error Comparator
FB
-
S
+
RS Latch
Logic
Gate
Driver
Power MOSFET
N-Channel
VREF = 1.233 V
R
Current Limit
EN
6 µs Max
On Time
RSENSE
+
_
Soft
Start
GND
2
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Copyright © 2002–2007, Texas Instruments Incorporated
Product Folder Link(s): TPS61040 TPS61041
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SLVS413C – OCTOBER 2002 – REVISED AUGUST 2007
Table 1. Terminal Functions
TERMINAL
I/O
DESCRIPTION
3
I
This is the enable pin of the device. Pulling this pin to ground forces the device into shutdown
mode reducing the supply current to less than 1 μA. This pin should not be left floating and needs
to be terminated.
3
4
I
This is the feedback pin of the device. Connect this pin to the external voltage divider to program
the desired output voltage.
GND
2
1
–
Ground
NC
–
5
–
No connection
SW
1
6
I
Connect the inductor and the Schottky diode to this pin. This is the switch pin and is connected to
the drain of the internal power MOSFET.
VIN
5
2
I
Supply voltage pin
NAME
DBV NO.
DRV NO.
EN
4
FB
DETAILED DESCRIPTION
OPERATION
The TPS61040/41 operates with an input voltage range of 1.8 V to 6 V and can generate output voltages up to
28 V. The device operates in a pulse-frequency-modulation (PFM) scheme with constant peak current control.
This control scheme maintains high efficiency over the entire load current range, and with a switching frequency
up to 1 MHz, the device enables the use of very small external components.
The converter monitors the output voltage, and as soon as the feedback voltage falls below the reference voltage
of typically 1.233 V, the internal switch turns on and the current ramps up. The switch turns off as soon as the
inductor current reaches the internally set peak current of typically 400 mA (TPS61040) or 250 mA (TPS61041).
See the Peak Current Control section for more information. The second criteria that turns off the switch is the
maximum on-time of 6 μs (typical). This is just to limit the maximum on-time of the converter to cover for extreme
conditions. As the switch is turned off the external Schottky diode is forward biased delivering the current to the
output. The switch remains off for a minimum of 400 ns (typical), or until the feedback voltage drops below the
reference voltage again. Using this PFM peak current control scheme the converter operates in discontinuous
conduction mode (DCM) where the switching frequency depends on the output current, which results in very high
efficiency over the entire load current range. This regulation scheme is inherently stable, allowing a wider
selection range for the inductor and output capacitor.
PEAK CURRENT CONTROL
The internal switch turns on until the inductor current reaches the typical dc current limit (ILIM) of 400 mA
(TPS61040) or 250 mA (TPS61042). Due to the internal propagation delay of typical 100 ns, theactualcurrent
exceeds the dc current limit threshold by a small amount. The typical peak current limit can be calculated:
V
I
+I
) IN
100 ns
peak(typ)
LIM
L
V
I
+ 400 mA ) IN
100 ns for the TPS61040
peak(typ)
L
V
I
+ 250 mA ) IN
100 ns for the TPS61041
peak(typ)
L
(1)
The higher the input voltage and the lower the inductor value, the greater the peak.
By selecting the TPS61040 or TPS61041, it is possible to tailor the design to the specific application current limit
requirements. A lower current limit supports applications requiring lower output power and allows the use of an
inductor with a lower current rating and a smaller form factor. A lower current limit usually has a lower output
voltage ripple as well.
Copyright © 2002–2007, Texas Instruments Incorporated
Product Folder Link(s): TPS61040 TPS61041
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SOFT START
All inductive step-up converters exhibit high inrush current during start-up if no special precaution is made. This
can cause voltage drops at the input rail during start up and may result in an unwanted or early system shut
down.
I LIM
The TPS61040/41 limits this inrush current by increasing the current limit in two steps starting from 4
for 256
I LIM
cycles to
2 for the next 256 cycles, and then full current limit (see Figure 14).
ENABLE
Pulling the enable (EN) to ground shuts down the device reducing the shutdown current to 1 μA (typical).
Because there is a conductive path from the input to the output through the inductor and Schottky diode, the
output voltage is equal to the input voltage during shutdown. The enable pin needs to be terminated and should
not be left floating. Using a small external transistor disconnects the input from the output during shutdown as
shown in Figure 18.
UNDERVOLTAGE LOCKOUT
An undervoltage lockout prevents misoperation of the device at input voltages below typical 1.5 V. When the
input voltage is below the undervoltage threshold, the main switch is turned off.
ABSOLUTE MAXIMUM RATINGS
over operating free-air temperature (unless otherwise noted)
(1)
UNIT
Supply voltages on pin VIN (2)
Voltages on pins EN, FB
–0.3 V to 7 V
(2)
Switch voltage on pin SW
–0.3 V to VIN + 0.3 V
(2)
30 V
Continuous power dissipation
See Dissipation Rating Table
TJ
Operating junction temperature
–40°C to 150°C
Tstg
Storage temperature
–65°C to 150°C
Lead temperature (soldering 10 seconds)
(1)
(2)
260°C
Stresses beyond those listed under absolute maximum ratings may cause permanent damage to the device. These are stress ratings
only, and functional operation of the device at these or any other conditions beyond those indicated under recommended operating
conditions is not implied. Exposure to absolute-maximum-rated conditions for extended periods may affect device reliability.
All voltage values are with respect to network ground terminal.
DISSIPATION RATING TABLE
4
DERATING
FACTOR
ABOVE
TA = 25°C
TA = 70°C
POWER RATING
TA = 85°C
POWER RATING
PACKAGE
RθJA
TA ≤ 25°C
POWER RATING
DBV
250°C/W
357 mW
3.5 mW/°C
192 mW
140 mW
DRV
76°C/W
1300 mW
13 mW/°C
688 mW
500 mW
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Product Folder Link(s): TPS61040 TPS61041
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SLVS413C – OCTOBER 2002 – REVISED AUGUST 2007
RECOMMENDED OPERATING CONDITIONS
MIN
TYP
MAX
VIN
Input voltage range
VOUT
Output voltage range
L
Inductor (1)
f
Switching frequency (1)
CIN
Input capacitor
COUT
Output capacitor
TA
Operating ambient temperature
–40
85
°C
TJ
Operating junction temperature
–40
125
°C
TYP
MAX
UNIT
(1)
1.8
6
UNIT
28
2.2
1
MHz
μF
4.7
(1)
V
μH
10
(1)
V
μF
1
See application section for further information.
ELECTRICAL CHARACTERISTICS
VIN = 2.4 V, EN = VIN, TA = –40°C to 85°C, typical values are at TA = 25°C (unless otherwise noted)
PARAMETER
TEST CONDITIONS
MIN
SUPPLY CURRENT
VIN
Input voltage range
6
V
IQ
Operating quiescent current
IOUT = 0 mA, not switching, VFB = 1.3 V
1.8
28
50
μA
ISD
Shutdown current
EN = GND
0.1
1
μA
VUVLO
Under-voltage lockout threshold
1.5
1.7
V
ENABLE
VIH
EN high level input voltage
VIL
EN low level input voltage
II
EN input leakage current
1.3
EN = GND or VIN
V
0.4
V
1
μA
30
V
0.1
POWER SWITCH AND CURRENT LIMIT
Vsw
Maximum switch voltage
toff
Minimum off time
250
400
550
ns
ton
Maximum on time
4
6
7.5
μs
RDS(on)
MOSFET on-resistance
VIN = 2.4 V; ISW = 200 mA; TPS61040
600
1000
mΩ
RDS(on)
MOSFET on-resistance
VIN = 2.4 V; ISW = 200 mA; TPS61041
750
1250
mΩ
MOSFET leakage current
VSW = 28 V
1
10
μA
ILIM
MOSFET current limit
TPS61040
350
400
450
mA
ILIM
MOSFET current limit
TPS61041
215
250
285
mA
28
V
OUTPUT
VOUT
Adjustable output voltage range
Vref
Internal voltage reference
IFB
Feedback input bias current
VFB = 1.3 V
VFB
Feedback trip point voltage
1.8 V ≤ VIN ≤ 6 V
Line regulation
VIN
1.233
(1)
Load regulation (1)
(1)
1.208
1.233
V
1
μA
1.258
V
1.8 V ≤ VIN ≤ 6 V; VOUT = 18 V; Iload = 10 mA;
CFF = not connected
0.05
%/V
VIN = 2.4 V; VOUT = 18 V; 0 mA ≤ IOUT ≤ 30 mA
0.15
%/mA
The line and load regulation depend on the external component selection. See the application section for further information.
Copyright © 2002–2007, Texas Instruments Incorporated
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TYPICAL CHARACTERISTICS
Table 2. Table of Graphs
FIGURE
vs Load current
1, 2, 3
η
Efficiency
vs Input voltage
4
IQ
Quiescent current
vs Input voltage and temperature
5
VFB
Feedback voltage
vs Temperature
6
ISW
Switch current limit
vs Temperature
7
ICL
Switch current limit
vs Supply voltage, TPS61041
8
RDS(on)
RDS(on)
vs Supply voltage, TPS61040
9
vs Temperature
10
vs Supply voltage
11
Line transient response
12
Load transient response
13
Start-up behavior
14
EFFICIENCY
vs
OUTPUT CURRENT
EFFICIENCY
vs
LOAD CURRENT
90
90
VO = 18 V
88
88
VI = 5 V
86
86
82
80
VI = 2.4 V
78
80
78
76
74
74
72
72
1
10
IO - Output Current - mA
100
TPS61041
82
76
70
0.10
TPS61040
84
VI = 3.6 V
Efficiency - %
Efficiency - %
84
L = 10 µH
VO = 18 V
70
0.10
1
10
IL - Load Current - mA
Figure 1.
6
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100
Figure 2.
Copyright © 2002–2007, Texas Instruments Incorporated
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TPS61041
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SLVS413C – OCTOBER 2002 – REVISED AUGUST 2007
EFFICIENCY
vs
LOAD CURRENT
EFFICIENCY
vs
INPUT VOLTAGE
90
88
90
VO = 18 V
86
IO = 10 mA
86
L = 10 µH
84
IO = 5 mA
84
L = 3.3 µH
82
Efficiency - %
Efficiency - %
L = 10 µH
VO = 18 V
88
80
78
82
80
78
76
76
74
74
72
72
70
70
0.10
1
10
IL - Load Current - mA
1
100
2
3
4
5
6
VI - Input Voltage - V
Figure 3.
Figure 4.
TPS61040
QUIESCENT CURRENT
vs
INPUT VOLTAGE
FEEDBACK VOLTAGE
vs
FREE-AIR TEMPERATIRE
40
1.24
TA = 85°C
35
VFB - Feedback Voltage - V
Quiescent Current - µ A
1.238
30
TA = 27°C
25
TA = -40°C
20
15
10
1.236
VCC = 2.4 V
1.234
1.232
5
0
1.8
2.4
3
3.6
4.2
4.8
5.4
6
1.23
-40
-20
VI - Input Voltage - V
Figure 5.
0
20
40
60
80
TA - Temperature - °C
100
120
Figure 6.
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SLVS413C – OCTOBER 2002 – REVISED AUGUST 2007
TPS61040/41
SWITCH CURRENT LIMIT
vs
FREE-AIR TEMPERATURE
TPS61041
CURRENT LIMIT
vs
SUPPLY VOLTAGE
260
430
TPS61040
258
390
256
I (CL) - Current Limit - mA
I (SW) - Switch Current Limit - mA
410
370
350
330
310
290
254
TA = 27°C
252
250
248
246
244
270
TPS61041
250
242
230
-40 -30 -20 -10 0 10 20 30 40 50 60 70 80 90
TA - Temperature - °C
240
1.8
2.4
Figure 7.
I (CL) - Current Limit - mA
415
410
TA = 27°C
400
395
390
385
2.4
3
3.6
4.2
4.8
VCC - Supply Voltage - V
5.4
6
r
− Static Drain-Source On-State Resistance − mΩ
DS(on)
420
380
1.8
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4.2
4.8
5.4
6
TPS61040/41
STATIC DRAIN-SOURCE ON-STATE RESISTANCE
vs
FREE-AIR TEMPERATURE
1200
1000
TPS61041
800
TPS61040
600
400
200
0
−40 −30 −20 −10 0 10 20 30 40 50 60 70 80 90
TA − Temperature − °C
Figure 9.
8
3.6
Figure 8.
TPS61040
CURRENT LIMIT
vs
SUPPLY VOLTAGE
405
3
VCC - Supply Voltage - V
Figure 10.
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Product Folder Link(s): TPS61040 TPS61041
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rDS(on) − Static Drain-Source On-State Resistance − mΩ
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SLVS413C – OCTOBER 2002 – REVISED AUGUST 2007
TPS61040/41
STATIC DRAIN-SOURCE ON-STATE RESISTANCE
vs
SUPPLY VOLTAGE
1000
VO = 18 V
900
VI
2.4 V to 3.4 V
800
TPS61041
700
600
TPS61040
500
400
VO
100 mV/div
300
200
100
0
1.8
2.4
3
3.6
4.2
4.8
5.4
200 µS/div
6
VCC − Supply Voltage − V
Figure 11.
Figure 12. Line Transient Response
VO = 18 V
VO = 18 V
VO
100 mA/div
VO
5 V/div
EN
1 V/div
VO
1 mA to 10 mA
II
50 mA/div
200 µS/div
Figure 13. Load Transient Tresponse
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Figure 14. Start-Up Behavior
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APPLICATION INFORMATION
INDUCTOR SELECTION, MAXIMUM LOAD CURRENT
Because the PFM peak current control scheme is inherently stable, the inductor value does not affect the stability
of the regulator. The selection of the inductor together with the nominal load current, input and output voltage of
the application determines the switching frequency of the converter. Depending on the application, inductor
values between 2.2 μH and 47 μH are recommended. The maximum inductor value is determined by the
maximum on time of the switch, typically 6 μs. The peak current limit of 400 mA/250 mA (typically) should be
reached within this 6-μs period for proper operation.
The inductor value determines the maximum switching frequency of the converter. Therefore, select the inductor
value that ensures the maximum switching frequency at the converter maximum load current is not exceeded.
The maximum switching frequency is calculated by the following formula:
V
(V
*V
IN(min)
OUT
IN)
fS max +
I
L V
P
OUT
(2)
Where:
IP = Peak current as described in the Peak Current Control section
L = Selected inductor value
VIN(min) = The highest switching frequency occurs at the minimum input voltage
If the selected inductor value does not exceed the maximum switching frequency of the converter, the next step
is to calculate the switching frequency at the nominal load current using the following formula:
2 I
(V
* V ) Vd)
load
OUT
IN
fS I
+
2
load
I
L
P
(3)
ǒ
Ǔ
Where:
IP = Peak current as described in the Peak Current Control section
L = Selected inductor value
Iload = Nominal load current
Vd = Rectifier diode forward voltage (typically 0.3V)
A smaller inductor value gives a higher converter switching frequency, but lowers the efficiency.
The inductor value has less effect on the maximum available load current and is only of secondary order. The
best way to calculate the maximum available load current under certain operating conditions is to estimate the
expected converter efficiency at the maximum load current. This number can be taken out of the efficiency
graphs shown in Figure 1 through Figure 4. The maximum load current can then be estimated as follows:
I 2 L fS max
I
+h P
load max
2 (V
*V
OUT
IN)
(4)
Where:
IP = Peak current as described in the Peak Current Control section
L = Selected inductor value
fSmax = Maximum switching frequency as calculated previously
η = Expected converter efficiency. Typically 70% to 85%
10
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The maximum load current of the conveter is the current at the operation point where the coverter starts to enter
the continuous conduction mode. Usually the converter should always operate in discontinuous conduction
mode.
Last, the selected inductor should have a saturation current that meets the maximum peak current of the
converter (as calculated in the Peak Current Control section). Use the maximum value for ILIMfor this calculation.
Another important inductor parameter is the dc resistance. The lower the dc resistance, the higher the efficiency
of the converter. See Table 3 and the typical applications for the inductor selection.
Table 3. Recommended Inductor for Typical LCD Bias Supply (see Figure 15)
DEVICE
TPS61040
TPS61041
INDUCTOR VALUE
COMPONENT SUPPLIER
COMMENTS
10 μH
Sumida CR32-100
High efficiency
10 μH
Sumida CDRH3D16-100
High efficiency
10 μH
Murata LQH4C100K04
High efficiency
4.7 μH
Sumida CDRH3D16-4R7
Small solution size
4.7 μH
Murata LQH3C4R7M24
Small solution size
10 μH
Murata LQH3C100K24
High efficiency
Small solution size
SETTING THE OUTPUT VOLTAGE
The output voltage is calculated as:
V
OUT
+ 1.233 V
ǒ1 ) R1
Ǔ
R2
(5)
For battery-powered applications, a high-impedance voltage divider should be used with a typical value for R2 of
≤200 kΩ and a maximum value for R1 of 2.2 MΩ. Smaller values might be used to reduce the noise sensitivity of
the feedback pin.
A feedforward capacitor across the upper feedback resistor R1 is required to provide sufficient overdrive for the
error comparator. Without a feedforward capacitor, or one whose value is too small, the TPS61040/41 shows
double pulses or a pulse burst instead of single pulses at the switch node (SW), causing higher output voltage
ripple. If this higher output voltage ripple is acceptable, the feedforward capacitor can be left out.
The lower the switching frequency of the converter, the larger the feedforward capacitor value required. A good
starting point is to use a 10-pF feedforward capacitor. As a first estimation, the required value for the feedforward
capacitor at the operation point can also be calculated using the following formula:
1
C
+
FF
fS
2 p
R1
20
(6)
Where:
R1 = Upper resistor of voltage divider
fS = Switching frequency of the converter at the nominal load current (See the INDUCTOR SELECTION,
MAXIMUM LOAD CURRENT section for calculating the switching frequency)
CFF = Choose a value that comes closest to the result of the calculation
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The larger the feedforward capacitor the worse the line regulation of the device. Therefore, when concern for line
regulation is paramount, the selected feedforward capacitor should be as small as possible. See the LINE AND
LOAD REGULATION section for more information about line and load regulation.
LINE AND LOAD REGULATION
The line regulation of the TPS61040/41 depends on the voltage ripple on the feedback pin. Usually a 50 mV
peak-to-peak voltage ripple on the feedback pin FB gives good results.
Some applications require a very tight line regulation and can only allow a small change in output voltage over a
certain input voltage range. If no feedforward capacitor CFF is used across the upper resistor of the voltage
feedback divider, the device has the best line regulation. Without the feedforward capacitor the output voltage
ripple is higher because the TPS61040/41 shows output voltage bursts instead of single pulses on the switch pin
(SW), increasing the output voltage ripple. Increasing the output capacitor value reduces the output voltage
ripple.
If a larger output capacitor value is not an option, a feedforward capacitor CFF can be used as described in the
previous section. The use of a feedforward capacitor increases the amount of voltage ripple present on the
feedback pin (FB). The greater the voltage ripple on the feedback pin (≥50 mV), the worse the line regulation.
There are two ways to improve the line regulation further:
1. Use a smaller inductor value to increase the switching frequency which will lower the output voltage ripple,
as well as the voltage ripple on the feedback pin.
2. Add a small capacitor from the feedback pin (FB) to ground to reduce the voltage ripple on the feedback pin
down to 50 mV again. As a starting point, the same capacitor value as selected for the feedforward capacitor
CFF can be used.
OUTPUT CAPACITOR SELECTION
For best output voltage filtering, a low ESR output capacitor is recommended. Ceramic capacitors have a low
ESR value but tantalum capacitors can be used as well, depending on the application.
Assuming the converter does not show double pulses or pulse bursts on the switch node (SW), the output
voltage ripple can be calculated as:
I
DV out + out
Cout
ǒ
Ǔ
I
L
1
P
–
fS(Iout) Vout ) Vd–Vin
)I
P
ESR
(7)
where:
IP = Peak current as described in the Peak Current Control section
L = Selected inductor value
Iout = Nominal load current
fS (Iout) = Switching frequency at the nominal load current as calculated previously
Vd = Rectifier diode forward voltage (typically 0.3 V)
Cout = Selected output capacitor
ESR = Output capacitor ESR value
See Table 4 and the typical applications section for choosing the output capacitor.
Table 4. Recommended Input and Output Capacitors
DEVICE
TPS61040/41
12
CAPACITOR
VOLTAGE RATING
COMPONENT SUPPLIER
COMMENTS
4.7 μF/X5R/0805
6.3 V
Tayo Yuden JMK212BY475MG
CIN/COUT
10 μF/X5R/0805
6.3 V
Tayo Yuden JMK212BJ106MG
CIN/COUT
1 μF/X7R/1206
25 V
Tayo Yuden TMK316BJ105KL
COUT
1 μF/X5R/1206
35 V
Tayo Yuden GMK316BJ105KL
COUT
4.7 μF/X5R/1210
25 V
Tayo Yuden TMK325BJ475MG
COUT
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Copyright © 2002–2007, Texas Instruments Incorporated
Product Folder Link(s): TPS61040 TPS61041
TPS61040
TPS61041
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SLVS413C – OCTOBER 2002 – REVISED AUGUST 2007
INPUT CAPACITOR SELECTION
For good input voltage filtering, low ESR ceramic capacitors are recommended. A 4.7 μF ceramic input capacitor
is sufficient for most of the applications. For better input voltage filtering this value can be increased. See Table 4
and typical applications for input capacitor recommendations.
DIODE SELECTION
To achieve high efficiency a Schottky diode should be used. The current rating of the diode should meet the
peak current rating of the converter as it is calculated in the Peak Current Control section. Use the maximum
value for ILIM for this calculation. See Table 5 and the typical applications for the selection of the Schottky diode.
Table 5. Recommended Schottky Diode for Typical LCD Bias Supply (see Figure 15)
DEVICE
REVERSE VOLTAGE
COMPONENT SUPPLIER
30 V
ON Semiconductor MBR0530
TPS61040/41
20 V
ON Semiconductor MBR0520
20 V
ON Semiconductor MBRM120L
30 V
Toshiba CRS02
COMMENTS
High efficiency
LAYOUT CONSIDERATIONS
Typical for all switching power supplies, the layout is an important step in the design; especially at high peak
currents and switching frequencies. If the layout is not carefully done, the regulator might show noise problems
and duty cycle jitter.
The input capacitor should be placed as close as possible to the input pin for good input voltage filtering. The
inductor and diode should be placed as close as possible to the switch pin to minimize the noise coupling into
other circuits. Because the feedback pin and network is a high-impedance circuit, the feedback network should
be routed away from the inductor. The feedback pin and feedback network should be shielded with a ground
plane or trace to minimize noise coupling into this circuit.
Wide traces should be used for connections in bold as shown in Figure 15. A star ground connection or ground
plane minimizes ground shifts and noise.
D1
L1
VO
VIN
VIN
SW
CFF
R1
CO
FB
CIN
EN
GND
R2
Figure 15. Layout Diagram
Copyright © 2002–2007, Texas Instruments Incorporated
Product Folder Link(s): TPS61040 TPS61041
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13
TPS61040
TPS61041
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SLVS413C – OCTOBER 2002 – REVISED AUGUST 2007
L1
10 µH
VIN
1.8 V to 6 V
D1
VOUT
18 V
TPS61040
VIN
CFF
22 pF
R1
2.2 MW
SW
C2
1 µF
FB
C1
4.7 µF
EN
GND
L1:
D1:
C1:
C2:
R2
160 kW
Sumida CR32-100
Motorola MBR0530
Tayo Yuden JMK212BY475MG
Tayo Yuden TMK316BJ105KL
Figure 16. LCD Bias Supply
L1
10 µH
D1
VO
18 V
TPS61040
VIN
1.8 V to 6 V
VIN
CFF
22 pF
R1
2.2 MW
SW
C2
1 µF
FB
C1
4.7 µF
EN
GND
DAC or Analog Voltage
0 V = 25 V
1.233 V = 18 V
R2
160 kW
L1:
D1:
C1:
C2:
Sumida CR32-100
Motorola MBR0530
Tayo Yuden JMK212BY475MG
Tayo Yuden GMK316BJ105KL
Figure 17. LCD Bias Supply With Adjustable Output Voltage
R3
200 kW
VIN
1.8 V to 6 V
L1
10 µH
TPS61040
VIN
C1
4.7 µF
SW
FB
EN
GND
BC857C
D1
VOUT
18 V / 10 mA
R1
2.2 MW
CFF
22 pF
C2
1 µF
C3
0.1 µF
(Optional)
R2
160 kW
L1:
D1:
C1:
C2:
Sumida CR32-100
Motorola MBR0530
Tayo Yuden JMK212BY475MG
Tayo Yuden TMK316BJ105KL
Figure 18. LCD Bias Supply With Load Disconnect
14
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Product Folder Link(s): TPS61040 TPS61041
TPS61040
TPS61041
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SLVS413C – OCTOBER 2002 – REVISED AUGUST 2007
D3
V2 = -10 V/15 mA
D2
C4
4.7 µF
C3
1 µF
L1
6.8 µH
D1
V1 = 10 V/15 mA
TPS61040
VIN
VIN = 2.7 V to 5 V
SW
R1
1.5 MW
CFF
22 pF
C2
1 µF
FB
C1
4.7 µF
EN
GND
L1:
D1, D2, D3:
C1:
C2, C3, C4:
R2
210 kW
Murata LQH4C6R8M04
Motorola MBR0530
Tayo Yuden JMK212BY475MG
Tayo Yuden EMK316BJ105KF
Figure 19. Positive and Negative Output LCD Bias Supply
L1
6.8 µH
D1
VO = 12 V/35 mA
TPS61040
VIN 3.3 V
C1
10 µF
VIN
R1
1.8 MW
SW
CFF
4.7 pF
C2
4.7 µF
FB
EN
GND
L1:
D1:
C1:
C2:
R2
205 kW
Murata LQH4C6R8M04
Motorola MBR0530
Tayo Yuden JMK212BJ106MG
Tayo Yuden EMK316BJ475ML
Figure 20. Standard 3.3-V to 12-V Supply
D1
3.3 µH
5 V/45 mA
TPS61040
1.8 V to 4 V
VIN
R1
620 kW
SW
FB
C1
4.7 µF
EN
R2
200 kW
GND
CFF
3.3 pF
C2
4.7 µF
L1:
D1:
C1, C2:
Murata LQH4C3R3M04
Motorola MBR0530
Tayo Yuden JMK212BY475MG
Figure 21. Dual Battery Cell to 5-V/50-mA Conversion
Efficiency Approx. Equals 84% at VIN = 2.4 V to Vo = 5 V/45 mA
Copyright © 2002–2007, Texas Instruments Incorporated
Product Folder Link(s): TPS61040 TPS61041
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15
TPS61040
TPS61041
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SLVS413C – OCTOBER 2002 – REVISED AUGUST 2007
L1
10 µH
VCC = 2.7 V to 6 V
VIN
D1
SW
C1
4.7 µF
D2
24 V
(Optional)
FB
EN
PWM
100 Hz to 500 Hz
C2
1 µF
GND
L1:
D1:
C1:
C2:
RS
82 Ω
Murata LQH4C100K04
Motorola MBR0530
Tayo Yuden JMK212BY475MG
Tayo Yuden TMK316BJ105KL
Figure 22. White LED Supply With Adjustable Brightness Control
Using a PWM Signal on the Enable Pin, Efficiency Approx. Equals 86% at VIN = 3 V, ILED = 15 mA
L1
10 µH
VCC = 2.7 V to 6 V
C1
4.7 µF
VIN
SW
D2
24 V
(Optional)
C2†
100 nF
FB
EN
R1
120 kW
GND
Analog Brightness Control
3.3 V≅ Led Off
0 V≅ Iled = 20 mA
A.
D1
MBRM120L
RS
110 W
R2 160 kW
L1:
D1:
C1:
C2:
Murata LQH4C3R3M04
Motorola MBR0530
Tayo Yuden JMK212BY475MG
Standard Ceramic Capacitor
A smaller output capacitor value for C2 causes a larger LED ripple.
Figure 23. White LED Supply With Adjustable Brightness Control
Using an Analog Signal on the Feedback Pin
16
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Product Folder Link(s): TPS61040 TPS61041
PACKAGE OPTION ADDENDUM
www.ti.com
15-Oct-2007
PACKAGING INFORMATION
Orderable Device
Status (1)
Package
Type
Package
Drawing
Pins Package Eco Plan (2)
Qty
TPS61040DBVR
ACTIVE
SOT-23
DBV
5
3000 Green (RoHS &
no Sb/Br)
CU NIPDAU
Level-1-260C-UNLIM
TPS61040DBVRG4
ACTIVE
SOT-23
DBV
5
3000 Green (RoHS &
no Sb/Br)
CU NIPDAU
Level-1-260C-UNLIM
TPS61040DRVR
PREVIEW
SON
DRV
6
3000
TPS61041DBVR
ACTIVE
SOT-23
DBV
5
3000 Green (RoHS &
no Sb/Br)
CU NIPDAU
Level-1-260C-UNLIM
TPS61041DBVRG4
ACTIVE
SOT-23
DBV
5
3000 Green (RoHS &
no Sb/Br)
CU NIPDAU
Level-1-260C-UNLIM
TPS61041DRVR
PREVIEW
SON
DRV
5
3000
TBD
Call TI
Call TI
TPS61041DRVT
PREVIEW
SON
DRV
5
250
TBD
Call TI
Call TI
TBD
Lead/Ball Finish
Call TI
MSL Peak Temp (3)
Call TI
(1)
The marketing status values are defined as follows:
ACTIVE: Product device recommended for new designs.
LIFEBUY: TI has announced that the device will be discontinued, and a lifetime-buy period is in effect.
NRND: Not recommended for new designs. Device is in production to support existing customers, but TI does not recommend using this part in
a new design.
PREVIEW: Device has been announced but is not in production. Samples may or may not be available.
OBSOLETE: TI has discontinued the production of the device.
(2)
Eco Plan - The planned eco-friendly classification: Pb-Free (RoHS), Pb-Free (RoHS Exempt), or Green (RoHS & no Sb/Br) - please check
http://www.ti.com/productcontent for the latest availability information and additional product content details.
TBD: The Pb-Free/Green conversion plan has not been defined.
Pb-Free (RoHS): TI's terms "Lead-Free" or "Pb-Free" mean semiconductor products that are compatible with the current RoHS requirements
for all 6 substances, including the requirement that lead not exceed 0.1% by weight in homogeneous materials. Where designed to be soldered
at high temperatures, TI Pb-Free products are suitable for use in specified lead-free processes.
Pb-Free (RoHS Exempt): This component has a RoHS exemption for either 1) lead-based flip-chip solder bumps used between the die and
package, or 2) lead-based die adhesive used between the die and leadframe. The component is otherwise considered Pb-Free (RoHS
compatible) as defined above.
Green (RoHS & no Sb/Br): TI defines "Green" to mean Pb-Free (RoHS compatible), and free of Bromine (Br) and Antimony (Sb) based flame
retardants (Br or Sb do not exceed 0.1% by weight in homogeneous material)
(3)
MSL, Peak Temp. -- The Moisture Sensitivity Level rating according to the JEDEC industry standard classifications, and peak solder
temperature.
Important Information and Disclaimer:The information provided on this page represents TI's knowledge and belief as of the date that it is
provided. TI bases its knowledge and belief on information provided by third parties, and makes no representation or warranty as to the
accuracy of such information. Efforts are underway to better integrate information from third parties. TI has taken and continues to take
reasonable steps to provide representative and accurate information but may not have conducted destructive testing or chemical analysis on
incoming materials and chemicals. TI and TI suppliers consider certain information to be proprietary, and thus CAS numbers and other limited
information may not be available for release.
In no event shall TI's liability arising out of such information exceed the total purchase price of the TI part(s) at issue in this document sold by TI
to Customer on an annual basis.
Addendum-Page 1
PACKAGE MATERIALS INFORMATION
www.ti.com
5-Oct-2007
TAPE AND REEL BOX INFORMATION
Device
Package Pins
Site
Reel
Diameter
(mm)
Reel
Width
(mm)
A0 (mm)
B0 (mm)
K0 (mm)
P1
(mm)
W
Pin1
(mm) Quadrant
TPS61040DBVR
DBV
5
SITE 48
179
8
3.2
3.2
1.4
4
8
Q3
TPS61041DBVR
DBV
5
SITE 48
179
8
3.2
3.2
1.4
4
8
Q3
Pack Materials-Page 1
PACKAGE MATERIALS INFORMATION
www.ti.com
5-Oct-2007
Device
Package
Pins
Site
Length (mm)
Width (mm)
Height (mm)
TPS61040DBVR
DBV
5
SITE 48
195.0
200.0
45.0
TPS61041DBVR
DBV
5
SITE 48
195.0
200.0
45.0
Pack Materials-Page 2
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