TI S63036

TPS63036
www.ti.com
SLVSB76 – AUGUST 2012
HIGH-EFFICIENCY SINGLE INDUCTOR BUCK-BOOST CONVERTER In Tiny WCSP
Check for Samples: TPS63036
FEATURES
DESCRIPTION
•
•
•
•
•
•
•
The TPS63036 is a non inverting buck-boost
converter able to provide a regulated output voltage
from an input supply that can be higher or lower than
the output voltage. The buck-boost converter is based
on a fixed frequency, pulse-width-modulation (PWM)
controller using synchronous rectification to obtain
maximum efficiency. At low load currents, the
converter enters Power Save Mode to maintain high
efficiency over a wide load current range. The Power
Save mode can be disabled, forcing the converter to
operate at a fixed switching frequency. The maximum
average current in the switches is limited to a typical
value of 1000 mA. The output voltage is
programmable using an external resistor divider. The
converter can be disabled to minimize battery drain.
During shutdown, the load is disconnected from the
battery. The device is packaged 8-pin WCSP
package measuring 1.854 mm x 1.076 mm (YFG).
1
2
•
•
•
•
Input Voltage Range: 1.8V to 5.5V
Real Buck or Boost operation
Adjustable and fixed output voltage version
Up to 94% Efficiency
Device Quiescent Current less than 50μA
Fixed and Adjustable Output Voltage Options
Power Save Mode for Improved Efficiency at
Low Output Power
Forced Fixed Frequency Operation and
Synchronization Possible
Load Disconnect During Shutdown
Over-Temperature Protection
Available in Small 1.854 mm x 1.076 mm,
WCSP-8 Package
APPLICATIONS
•
•
•
•
•
•
All Two-Cell and Three-Cell Alkaline, NiCd or
NiMH or Single-Cell Li Battery Powered
Products
Portable Audio Players
PDAs
Cellular Phones
Personal Medical Products
White LEDs
L1
1.5µH
VIN
1.8 V to 5.5 V
L1
VIN
C1
VOUT
3.3V/600mA
L2
VOUT
R1
287kΩ
EN
10µF
PS/SYNC
C2
3X10µF
FB
R2
GND
51.1kΩ
TPS63036
Figure 1. Typical Circuit
1
2
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.
Buck-Boost Overlap Control is a trademark of Texas Instruments.
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 © 2012, Texas Instruments Incorporated
TPS63036
SLVSB76 – AUGUST 2012
www.ti.com
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.
AVAILABLE OUTPUT VOLTAGE OPTIONS
(1)
TA
OUTPUT VOLTAGE
DC/DC
PACKAGE MARKING
PACKAGE
PART NUMBER
–40°C to 85°C
Adjustable
S63036
8-WCSP
TPS63036YFG
(1)
For the most current package and ordering information, see the Package Option Addendum at the end of this document, or see the TI
web site at www.ti.com
ABSOLUTE MAXIMUM RATINGS
over operating free-air temperature range (unless otherwise noted) (1)
TPS63036
Input voltage range on VIN, L1, L2, VOUT, PS/SYNC, EN, FB
–0.3 V to 7 V
Operating virtual junction temperature range, TJ
–40°C to 150°C
Storage temperature range Tstg
–65°C to 150°C
(1)
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 my affect device reliability.
DISSIPATION RATINGS TABLE
(1)
PACKAGE (1)
THERMAL RESISTANCE
ΘJA
POWER RATING
TA ≤ 25°C
DERATING FACTOR ABOVE
TA = 25°C
YFG
84 °C/W
1190 mW
12 mW/°C
For the most current package and ordering information, see the Package Option Addendum at the end of this document, or see the TI
website at www.ti.com.
RECOMMENDED OPERATING CONDITIONS
MIN
NOM
MAX UNIT
Supply voltage at VIN
1.8
5.5
V
Operating free air temperature range, TA
–40
85
°C
Operating virtual junction temperature range, TJ
–40
125
°C
2
Submit Documentation Feedback
Copyright © 2012, Texas Instruments Incorporated
Product Folder Links: TPS63036
TPS63036
www.ti.com
SLVSB76 – AUGUST 2012
ELECTRICAL CHARACTERISTICS
over recommended free-air temperature range and over recommended input voltage range (typical at an ambient temperature
range of 25°C) (unless otherwise noted)
DC/DC STAGE
PARAMETER
VIN
Input voltage range
VOUT
TPS63036 output voltage range
TEST CONDITIONS
MIN
V
5.5
V
505
mV
20%
TPS63036 feedback voltage
PS/SYNC = VIN Io<5mA
495
VFB
TPS63036 feedback voltage
PS/SYNC = GND Referenced to 500mV
Io<5mA
-3%
Load Regulation
PS/SYNC = GND
ISW
UNIT
5.5
VFB
f
MAX
1.2
1.8
Duty cycle in step down conversion
TYP
(1)
500
+6%
0.008
%/mA
Oscillator frequency
1800
2000
2200
kHz
Frequency range for synchronization
2200
2400
2600
kHz
Average input current limit
VIN = 3.6 V, TA = 25°C (2)
High side switch on resistance
Low side switch on resistance
1000
mA
VIN = 3.6 V
200
mΩ
VIN = 3.6 V
200
mΩ
Line regulation
0.5%
VIN
Iq
Quiescent
current
IS
Shutdown current
VOUT
35
μA
4
6
μA
0.1
0.9
μA
IO = 0 mA, VEN = VIN = 3.6 V,
VOUT = 3.3 V
25
VEN = 0 V, VIN = 3.6 V
CONTROL STAGE
VUVLO
Under voltage lockout threshold falling
1.4
1.5
1.6
V
Under voltage lockout threshold raising
1.6
1.8
2.0
V
0.4
V
0.1
μA
VIL
EN, PS/SYNC input low voltage
VIH
EN, PS/SYNC input high voltage
EN, PS/SYNC input current
(1)
(2)
1.2
Clamped on GND or VIN
V
0.01
Overtemperature protection
140
°C
Overtemperature hysteresis
20
°C
The typical required supply voltage for startup is 2V. The part is functional down to 1.8V.
For the minimum specified average input current limit at VOUT = 2.5V, 3.3V and 4.5V refer to curve in Figure 3. For the maximum
specified average input current limit at VOUT = 2.5V, 3.3V and 4.5V refer to curve in Figure 4.
Submit Documentation Feedback
Copyright © 2012, Texas Instruments Incorporated
Product Folder Links: TPS63036
3
TPS63036
SLVSB76 – AUGUST 2012
www.ti.com
PIN ASSIGNMENTS
A2
B2
C2
D2
A1
B1
C1
D1
Figure 2. WCSP (YFG) Package - Top view
Terminal Functions
TERMINAL
NAME
NO.
I/O
DESCRIPTION
EN
A2
I
Enable input. (1 enabled, 0 disabled)
FB
D2
I
Voltage feedback of adjustable versions, must be connected to VOUT on fixed output voltage versions
GND
C2
PS/SYNC
B2
I
Enable / disable power save mode (1 disabled, 0 enabled, clock signal for synchronization)
L1
B1
I
Connection for Inductor
L2
C1
I
Connection for Inductor
VIN
A1
I
Supply voltage for power stage
VOUT
D1
O
Buck-boost converter output
4
Control / logic ground
Submit Documentation Feedback
Copyright © 2012, Texas Instruments Incorporated
Product Folder Links: TPS63036
TPS63036
www.ti.com
SLVSB76 – AUGUST 2012
FUNCTIONAL BLOCK DIAGRAM (TPS63036)
L1
L2
VIN
VOUT
Current
Sensor
GND
GND
VBAT
VOUT
Gate
Control
_
VIN
Modulator
+
+
_
FB
VREF
Oscillator
PS/SYNC
+
-
Device
Control
EN
Temperature
Control
GND
Submit Documentation Feedback
Copyright © 2012, Texas Instruments Incorporated
Product Folder Links: TPS63036
5
TPS63036
SLVSB76 – AUGUST 2012
www.ti.com
TYPICAL CHARACTERISTICS
TABLE OF GRAPHS
DESCRIPTION1
FIGURE
Minimum input current
vs Input voltage (TPS63036, VOUT = 2.5 V VOUT = 3.3V VOUT = 4.5 V)
3
Maximum input current
vs Input voltage (TPS63036, VOUT = 2.5 V VOUT = 3.3V VOUT = 4.5 V)
4
vs Output current (TPS63036, Power Save Enabled, VOUT = 2.5 V / VOUT = 4.5 V)
5
vs Output current (TPS63036, Power Save Disabled, VOUT = 2.5 V / VOUT = 4.5 V)
6
vs Output current (TPS63036, Power Save Enabled, VOUT = 3.3 V)
7
vs Output current (TPS63036, Power Save Disabled, VOUT = 3.3 V)
8
vs Input voltage (TPS63036, Power Save Enabled, VOUT = 2.5V, IOUT = {10; 100; 500
mA})
9
vs Input voltage (TPS63036, Power Save Disabled, VOUT = 2.5V, IOUT = {10; 100; 500
mA})
10
vs Input voltage (TPS63036, Power Save Enabled, VOUT = 3.3V, IOUT = {10; 100; 500
mA})
11
vs Input voltage (TPS63036, Power Save Disabled, VOUT = 3.3V, IOUT = {10; 100; 500
mA})
12
vs Input voltage (TPS63036, Power Save Enabled, VOUT = 4.5V, IOUT = {10; 100; 500
mA})
13
vs Input voltage (TPS63036, Power Save Disabled, VOUT = 4.5V, IOUT = {10; 100; 500
mA})
14
vs Output current (TPS63036,Power Save Disabled, VOUT = 2.5 V)
15
vs Output current (TPS63036, Power Save Disabled, VOUT = 3.3 V)
16
vs Output current (TPS63036, Power Save Disabled, VOUT = 4.5V)
17
Load transient response (TPS63036, VIN < VOUT, Load change from 0 mA to 150 mA)
18
Load transient response (TPS63036, VIN > VOUT, Load change from 0 mA to 150 mA)
19
Line transient response (TPS63036, VOUT = 3.3V, IOUT = 150 mA)
20
Startup after enable (TPS63036, VOUT = 3.3V, VIN = 2.4V, RL=33Ω)
21
Startup after enable (TPS63036, VOUT = 3.3V, VIN = 4.2V, RL=33Ω)
22
Efficiency
Output voltage
Waveforms
MINIMUM INPUT CURRENT
vs
INPUT VOLTAGE
MAXIMUM INPUT CURRENT
vs
INPUT VOLTAGE
1.4
1.4
1.2
1.2
VOUT= 4.5V
1
1
Input Current - A
Input Current - A
VOUT= 4.5V
0.8
VOUT= 3.3V
0.6
VOUT= 2.5V
0.4
VOUT= 3.3V
0.6
VOUT= 2.5V
0.4
0.2
0.2
0
1.8
0.8
2.2
2.6
3
3.4
3.8
4.2
4.6
5
5.4
5.8
0
1.8
2.2
Input Voltage - V
3
3.4
3.8
4.2
4.6
5
5.4
5.8
Input Voltage - V
Figure 3.
6
2.6
Figure 4.
Submit Documentation Feedback
Copyright © 2012, Texas Instruments Incorporated
Product Folder Links: TPS63036
TPS63036
www.ti.com
SLVSB76 – AUGUST 2012
EFFICIENCY
vs
OUTPUT CURRENT
EFFICIENCY
vs
OUTPUT CURRENT
100
100
VIN =3.6V VOUT=2.5V
VIN =3.6V VOUT=4.5V
90
90
80
80
70
70
60
50
Efficiency- %
Efficiency- %
VIN =2.4V VOUT=2.5V
VIN =3.6V VOUT=4.5V
VIN =2.4V VOUT=4.5V
40
60
40
30
20
20
10
10
1
10
100
VIN =3.6V VOUT=
=2.5V
50
30
0
0.1
VIN =
=2.4V VOUT=2.5V
VIN =2.
=2.4V VOUT=4.5V
0
0.1
1000
1
10
100
Output Current - mA
Output Current - mA
Figure 5.
Figure 6.
EFFICIENCY
vs
OUTPUT CURRENT
EFFICIENCY
vs
OUTPUT CURRENT
100
1000
100
90
90
80
80
70
Efficiency- %
Efficiency- %
VIN =3.6V VOUT=3.3V
VIN =2.4V VOUT=3.3V
60
50
40
70
60
VIN =2.4V VOUT=3.3V
50
40
30
30
20
20
10
10
0
0.1
1
10
100
1000
VIN =3.6V VOUT=3.3V
0
0.1
Output Current - mA
1
10
100
1000
Output Current - mA
Figure 7.
Figure 8.
Submit Documentation Feedback
Copyright © 2012, Texas Instruments Incorporated
Product Folder Links: TPS63036
7
TPS63036
SLVSB76 – AUGUST 2012
www.ti.com
EFFICIENCY
vs
INPUT VOLTAGE
EFFICIENCY
vs
INPUT VOLTAGE
100
100
VOUT= 2.5V
VOUT= 2.5V
IOUT= 100mA
80
IOUT=10mA
IOUT= 100mA
IOUT= 500mA
70
Efficiency - %
Efficiency - %
80
IOUT= 500mA
90
90
60
50
40
70
IOUT=10mA
60
50
40
30
30
20
20
10
10
Power Save Enabled
0
1.8
2.2
2.6
3
3.4
3.8
4.2
4.6
5
5.4
Power Save Disabled
0
1.8
5.8
3
3.4
3.8
4.6
Figure 10.
EFFICIENCY
vs
INPUT VOLTAGE
EFFICIENCY
vs
INPUT VOLTAGE
5
5.4
5.8
100
VOUT= 3.3V
90 I = 100mA
OUT
90
80
80
IOUT=10mA
IOUT= 100mA
IOUT= 500mA
IOUT= 500mA
Efficiency - %
70
60
50
40
60
50
IOUT=10mA
40
30
30
20
20
10
10
Power Save Enabled
0
1.8
8
4.2
Figure 9.
VOUT= 3.3V
Efficiency - %
2.6
Input Voltage - V
100
70
2.2
Input Voltage - V
2.2
2.6
3
3.4
3.8
4.2
4.6
5
5.4
5.8
Power Save Disabled
0
1.8
2.2
2.6
3
3.4
3.8
4.2
4.6
Input Voltage - V
Input Voltage - V
Figure 11.
Figure 12.
Submit Documentation Feedback
5
5.4
5.8
Copyright © 2012, Texas Instruments Incorporated
Product Folder Links: TPS63036
TPS63036
www.ti.com
SLVSB76 – AUGUST 2012
EFFICIENCY
vs
INPUT VOLTAGE
EFFICIENCY
vs
INPUT VOLTAGE
100
100
VOUT= 4.5V
90
VOUT= 4.5V
IOUT= 100mA
90
IOUT= 500mA
80
IOUT= 500mA
70
Efficiency - %
Efficiency - %
80
60
IOUT=10mA
50
40
70
60
50
IOUT=10mA
40
30
30
20
20
10
IOUT= 100mA
10
Power Save Disabled
Power Save Enabled
0
1.8
2.2
2.6
3
3.4
3.8
4.2
4.6
5
5.4
0
1.8
5.8
2.2
2.6
3
3.4
3.8
4.2
4.6
Input Voltage - V
Input Voltage - V
Figure 13.
Figure 14.
OUTPUT VOLTAGE
vs
OUTPUT CURRENT
OUTPUT VOLTAGE
vs
OUTPUT CURRENT
5
5.4
5.8
3.432
2.575
VOUT= 2.5 V
VOUT= 3.3 V
VIN= 3.6 V
VIN= 3.6 V
2.55
Output Voltage - V
Output Voltage - V
3.399
2.525
2.5
2.475
3.366
3.333
3.3
2.45
Power Save Disabled
Power Save Disabled
3.267
2.425
1
10
100
1000
1
10
100
1000
Output Current - mA
Output Current - mA
Figure 15.
Figure 16.
Submit Documentation Feedback
Copyright © 2012, Texas Instruments Incorporated
Product Folder Links: TPS63036
9
TPS63036
SLVSB76 – AUGUST 2012
www.ti.com
OUTPUT VOLTAGE
vs
OUTPUT CURRENT
4.85
VOUT= 4.5 V
VIN= 3.6 V
Output Voltage - V
4.76
4.67
4.58
4.49
Power Save Disabled
4.4
1
10
100
1000
Output Current - mA
Figure 17.
LOAD TRANSIENT RESPONSE
LOAD TRANSIENT RESPONSE
VIN= 4.2 V, IOUT= 0A to 150mA
VIN= 2.4 V, IOUT= 0A to 150mA
Output Voltage
50mV/div, AC
Output Voltage
50mV/div, AC
Output Current
100mA/div
VOUT= 3.3 V
10
Output Current
100mA/div
VOUT= 3.3 V
Time 1ms/Div
Time 1ms/Div
Figure 18.
Figure 19.
Submit Documentation Feedback
Copyright © 2012, Texas Instruments Incorporated
Product Folder Links: TPS63036
TPS63036
www.ti.com
SLVSB76 – AUGUST 2012
LINE TRANSIENT RESPONSE
STARTUP AFTER ENABLE
VIN= 3 V to 3.6 V, IOUT= 150mA
Enable Voltage
5V/div, DC
Output Voltage
1V/div, DC
Input Voltage
500mV/div, AC
Inductor Current
200mA/div
Output Voltage
20mV/div, AC
Voltage at L2
2V/div, DC
VOUT= 3.3 V
VOUT= 3.3 V
VIN= 2.4 V, RL= 33S
Time 2ms/Div
Time 100:s/Div
Figure 20.
Figure 21.
STARTUP AFTER ENABLE
Enable Voltage
5V/div, DC
Output Voltage
1V/div, DC
Inductor Current
200mA/div
Voltage at L1
2V/div, DC
VIN= 4.2 V, RL= 33S
VOUT= 3.3 V
Time 100:s/Div
Figure 22.
Submit Documentation Feedback
Copyright © 2012, Texas Instruments Incorporated
Product Folder Links: TPS63036
11
TPS63036
SLVSB76 – AUGUST 2012
www.ti.com
PARAMETER MEASUREMENT INFORMATION
L1
1.5µH
VIN
1.8 V to 5.5 V
L1
VIN
VOUT
R1
287kΩ
EN
C1
VOUT
3.3V/600mA
L2
10µF
PS/SYNC
C2
3X10µF
FB
R2
GND
51.1kΩ
TPS63036
Figure 23. Parameter Measurement Circuit
Table 1. List of Components
REFERENCE
DESCRIPTION
MANUFACTURER
TPS63036
Texas Instruments
L1
1.5 μH, 3 mm x 3 mm x 1.5 mm
Coilcraft, LPS3015-152MLC
C1
10 μF 6.3V, 0603, X7R ceramic
GRM188R60J106KME84D, Murata
C2
3 × 10 μF 6.3V, 0603, X7R ceramic
GRM188R60J106KME84D, Murata
R1, R2
Depending on the output voltage at TPS63036
12
Submit Documentation Feedback
Copyright © 2012, Texas Instruments Incorporated
Product Folder Links: TPS63036
TPS63036
www.ti.com
SLVSB76 – AUGUST 2012
DETAILED DESCRIPTION
The controller circuit of the device is based on an average current mode topology. The controller also uses input
and output voltage feedforward. Changes of input and output voltage are monitored and immediately can change
the duty cycle in the modulator to achieve a fast response to those errors. The voltage error amplifier gets its
feedback input from the FB pin. A resistive voltage divider must be connected to that pin. The feedback voltage
will be compared with the internal reference voltage to generate a stable and accurate output voltage.
The device uses 4 internal N-channel MOSFETs to maintain synchronous power conversion at all possible
operating conditions. This enables the device to keep high efficiency over a wide input voltage and output power
range. Due to the 4-switch topology, the load is always disconnected from the input during shutdown of the
converter. To protect the device from overheating an internal temperature sensor is implemented.
Buck-Boost Operation
To regulate the output voltage at all possible input voltage conditions, the device automatically switches from
step down operation to boost operation and back as required by the configuration. It always uses one active
switch, one rectifying switch, one switch permanently on, and one switch permanently off. Therefore, it operates
as a step down converter (buck) when the input voltage is higher than the output voltage, and as a boost
converter when the input voltage is lower than the output voltage. There is no mode of operation in which all 4
switches are permanently switching. Controlling the switches this way allows the converter to maintain high
efficiency at the most important point of operation, when input voltage is close to the output voltage. The RMS
current through the switches and the inductor is kept at a minimum, to minimize switching and conduction losses.
For the remaining 2 switches, one is kept permanently on and the other is kept permanently off, thus causing no
switching losses.
Control loop description
The average inductor current is regulated by a fast current regulator loop which is controlled by a voltage control
loop. Figure 1 shows the control loop.
The non inverting input of the transconductance amplifier Gmv can be assumed to be constant. The output of
Gmv defines the average inductor current. The inductor current is reconstructed measuring the current through
the high side buck MOSFET. This current corresponds exactly to the inductor current in boost mode. In buck
mode the current is measured during the on time of the same MOSFET. During the off time the current is
reconstructed internally starting from the peak value reached at the end of the on time cycle. The average
current is then compared to the desired value and the difference, or current error, is amplified and compared to
the sawtooth ramp of either the Buck or the Boost.
The Buck-Boost Overlap Control™ makes sure that the classical buck-boost function, which would cause two
switches to be on every half a cycle, is avoided. Thanks to this block whenever all switches becomes active
during one clock cycle, the two ramps are shifted away from each other, on the other hand when there is no
switching activities because there is a gap between the ramps, the ramps are moved closer together. As a result
the number of classical buck-boost cycles or no switching is reduced to a minimum and high efficiency values
has been achieved.
Slope compensation is not required to avoid subharmonic oscillation which are otherwise observed when working
with peak current mode control with D > 0.5.
Nevertheless the amplified inductor current downslope at one input of the PWM comparator must not exceed the
oscillator ramp slope at the other comparator input. This purpose is reached limiting the gain of the current
amplifier.
Submit Documentation Feedback
Copyright © 2012, Texas Instruments Incorporated
Product Folder Links: TPS63036
13
TPS63036
SLVSB76 – AUGUST 2012
www.ti.com
TM
Figure 24. Average Current Mode Control
Power-save mode and synchronization
The PS/SYNC pin can be used to select different operation modes. Power Save Mode is used to improve
efficiency at light load. To enable Power Save Mode, PS/SYNC must be set low. If PS/SYNC is set low then
Power Save Mode is entered when the average inductor current gets lower then about 100mA. At this point the
converter operates with reduced switching frequency and with a minimum quiescent current to maintain high
efficiency.
During the Power Save Mode, the output voltage is monitored with a comparator by the threshold comp low and
comp high. When the device enters Power Save Mode, the converter stops operating and the output voltage
drops. The slope of the output voltage depends on the load and the value of output capacitance. As the output
voltage falls below the comp low threshold, the device ramps up the output voltage again, by starting operation
using a programmed average inductor current higher than required by the current load condition. Operation can
last one or several pulses. The converter continues these pulses until the comp high threshold, is reached and
the average inductance current gets lower than about 100mA. When the load increases above the minimum
forced inductor current of about 100mA, the device will automatically switch to PWM mode.
The Power Save Mode can be disabled by programming high at the PS/SYNC. Connecting a clock signal at
PS/SYNC forces the device to synchronize to the connected clock frequency.
Synchronization is done by a PLL, so synchronizing to lower and higher frequencies compared to the internal
clock works without any issues. The PLL can also tolerate missing clock pulses without the converter
malfunctioning. The PS/SYNC input supports standard logic thresholds.
Current Limit
To protect the device and the application, the average input current is limited internally on the IC. At nominal
operating conditions, this current limit is constant. The current limit value can be found in the electrical
characteristics table. The current limit varies depending on the input voltage. A curve of the input current varying
with the input voltage is shown in figure 3 and figure 4 respectively showing the minimum and the maximum
current limit expected depending on input and output voltage.
14
Submit Documentation Feedback
Copyright © 2012, Texas Instruments Incorporated
Product Folder Links: TPS63036
TPS63036
www.ti.com
SLVSB76 – AUGUST 2012
Given the average input current in figure 3 is then possible to calculate the output current reached in boost mode
using Equation 1 and Equation 2 and in buck mode using Equation 3 and Equation 4.
Duty Cycle Boost
D=
V
-V
IN
OUT
V
OUT
Maximum Output Current Boost
Duty Cycle Buck
D=
(1)
I
=hxI
x (1 - D)
OUT
SW
(2)
V
OUT
V
IN
Maximum Output Current Buck
(3)
Iout=
0 x Isw
D
(4)
With,
η = Estimated converter efficiency (use the number from the efficiency curves or 0.80 as an assumption)
f = Converter switching frequency (typical 2MHz)
L = Selected inductor value
ISW=Minimum average input current (Figure 3)
Device Enable
The device is put into operation when EN is set high. It is put into a shutdown mode when EN is set to GND. In
shutdown mode, the regulator stops switching, all internal control circuitry is switched off, and the load is
disconnected from the input. This means that the output voltage can drop below the input voltage during
shutdown. During start-up of the converter, the duty cycle and the peak current are limited in order to avoid high
peak currents flowing from the input.
Softstart and Short Circuit Protection
After being enabled, the device starts operating. The average input current limit ramps up from an initial 400mA
following the output voltage increasing. At an output voltage of about 1.2V, the current limit is at its nominal
value. If the output voltage does not increase, the current limit will not increase. The device ramps up the output
voltage in a controlled manner even if a large capacitor is connected at the output. When the output voltage does
not increase above 1.2V, the device assumes a short circuit at the output, and keeps the current limit low to
protect itself and the application. At a short on the output during operation, the current limit also is decreased
accordingly.
Overvoltage Protection
If, for any reason, the output voltage is not fed back properly to the input of the voltage amplifier, control of the
output voltage will not work anymore. Therefore overvoltage protection is implemented to avoid the output
voltage exceeding critical values for the device and possibly for the system it is supplying. The implemented
overvoltage protection circuit monitors the output voltage internally as well. In case it reaches the overvoltage
threshold the voltage amplifier regulates the output voltage to this value.
Undervoltage Lockout
An undervoltage lockout function prevents device start-up if the supply voltage on VIN is lower than
approximately its threshold (see electrical characteristics table). When in operation, the device automatically
enters the shutdown mode if the voltage on VIN drops below the undervoltage lockout threshold. The device
automatically restarts if the input voltage recovers to the minimum operating input voltage.
Overtemperature Protection
The device has a built-in temperature sensor which monitors the internal IC temperature. If the temperature
exceeds the programmed threshold (see electrical characteristics table) the device stops operating. As soon as
the IC temperature has decreased below the programmed threshold, it starts operating again. There is a built-in
hysteresis to avoid unstable operation at IC temperatures at the overtemperature threshold.
Submit Documentation Feedback
Copyright © 2012, Texas Instruments Incorporated
Product Folder Links: TPS63036
15
TPS63036
SLVSB76 – AUGUST 2012
www.ti.com
APPLICATION INFORMATION
DESIGN PROCEDURE
The TPS63036 buck-boost converter has internal loop compensation. Therefore, the external L-C filter has to be
selected to work with the internal compensation. As a general rule of thumb, the product L×C should not move
over a wide range when selecting a different output filter. However, when selecting the output filter a low limit for
the inductor value exists to avoid subharmonic oscillation which could be caused by a far too fast ramp up of the
amplified inductor current. For the TPS63036 the minimum inductor value should be kept at 1uH. To simplify this
process Table 2 outlines possible inductor and capacitor value combinations.
Table 2. Output Filter Selection (Average Inductance current up to 1A)
OUTPUT CAPACITOR VALUE [µF] (2)
INDUCTOR VALUE [µH] (1)
30
44
66
1.0
√
√
√
1.5
√ (3)
√
√
√
2.2
(1)
(2)
(3)
Inductor tolerance and current de-rating is anticipated. The effective inductance can vary by 20% and –30%.
Capacitance tolerance and bias voltage de-rating is anticipated. The effective capacitance can vary by 20% and –50%.
Typical application. Other check mark indicates recommended filter combinations
Inductor Selection
For high efficiencies, the inductor should have a low dc resistance to minimize conduction losses. Especially at
high-switching frequencies the core material has a higher impact on efficiency. When using small chip inductors,
the efficiency is reduced mainly due to higher inductor core losses. This needs to be considered when selecting
the appropriate inductor. The inductor value determines the inductor ripple current. The larger the inductor value,
the smaller the inductor ripple current and the lower the conduction losses of the converter. Conversely, larger
inductor values cause a slower load transient response. To avoid saturation of the inductor, with the chosen
inductance value, the peak current for the inductor in steady state operation can be calculated. Only the equation
which defines the switch current in boost mode is reported because this is providing the highest value of current
and represents the critical current value for selecting the right inductor.
Duty Cycle Boost
I
PEAK
= I
SW_MAX +
D=
Vout - Vin
Vout
(5)
Vin x D
2xfxL
(6)
With,
D =Duty Cycle in Boost mode
f = Converter switching frequency (typical 2 MHz)
L = Selected inductor value
η = Estimated converter efficiency (use the number from the efficiency curves or 0.80 as an assumption)
ISW_MAX=Maximum average input current (Figure 4)
Note: The calculation must be done for the minimum input voltage which is possible to have in boost mode
Consideration must be given to the load transients and error conditions that can cause higher inductor currents.
This must be taken into consideration when selecting an appropriate inductor. Please refer to Table 3 for typical
inductors.
The size of the inductor can also affect the stability of the feedback loop. In particular the boost transfer function
exhibits a right half-plane zero, whose frequency is inverse proportional to the inductor value and the load
current. This means higher is the value of inductance and load current more possibilities has the right plane zero
to be moved at lower frequency. This could degrade the phase margin of the feedback loop. It is recommended
to choose the inductor's value in order to have the frequency of the right half plane zero >400KHz. The frequency
of the RHPZ can be calculated using equation (3)
16
Submit Documentation Feedback
Copyright © 2012, Texas Instruments Incorporated
Product Folder Links: TPS63036
TPS63036
www.ti.com
f RHPZ =
SLVSB76 – AUGUST 2012
(1 - D)2 ´ Vout
2p ´ Iout ´ L
(7)
With,
D =Duty Cycle in Boost mode
Note: The calculation must be done for the minimum input voltage which is possible to have in boost mode
Table 3. Inductor Selection
INDUCTOR VALUE
COMPONENT SUPPLIER
SIZE (LxWxH mm)
Isat/DCR
1 µH
TOKO 1286AS-H-1R0M
2x1.6x1.2
2.3A/78mΩ
1 µH
Coilcraft XFL4020-102
4 x 4 x 2.1
5.1A/10.8 mΩ
1 µH
Coilcraft XFL3012-102
3 x 3 x 1.2
2.2 A/35 mΩ
1.5µH
TOKO, 1286AS-H-1R5M
2 x 1.6 x 1.2
4.4A/ 14.40mΩ
1.5µH
Coilcraft, LPS3015-152MLC
3 x 3 x 1.5
2.1A/100mΩ
1.5µH
TOKO, 1269AS-H-1R5M
2.5 x 2 x 1
2.1A/108mΩ
2.2µH
TOKO D1286AS-H-2R2M
2 x 1.6 x 1.2
1.6A/192mΩ
Capacitor selection
Input Capacitor
At least a 10μF input capacitor is recommended to improve transient behavior of the regulator and EMI behavior
of the total power supply circuit. A ceramic capacitor placed as close as possible to the VIN and GND pins of the
IC is recommended.
Output Capacitor
For the output capacitor, use of a small ceramic capacitors placed as close as possible to the VOUT and GND
pins of the IC is recommended. If, for any reason, the application requires the use of large capacitors which can
not be placed close to the IC, use a smaller ceramic capacitor in parallel to the large capacitor. The small
capacitor should be placed as close as possible to the VOUT and GND pins of the IC. The recommended typical
output capacitor value is 30 µF.
There is also no upper limit for the output capacitance value. Larger capacitors will cause lower output voltage
ripple as well as lower output voltage drop during load transients.
When choosing input and output capacitors, it needs to be kept in mind, that the value of capacitance
experiences significant losses from their rated value depending on the operating temperature and the operating
DC voltage. It's not uncommon for a small surface mount ceramic capacitor to lose 50% and more of it's rated
capacitance. For this reason could be important to use a larger value of capacitance or a capacitor with higher
voltage rating in order to ensure the required capacitance at the full operating voltage.
Setting the Output Voltage
The output voltage of the TPS63036 is set by an external resistor divider. The resistor divider must be connected
between VOUT, FB and GND. When the output voltage is regulated, the typical value of the voltage at the FB pin
is 500mV. The maximum recommended value for the output voltage is 5.5V. The typical current into the FB pin is
0.01μA, and the voltage across the resistor between FB and GND, R2, is typically 500 mV. Based on these two
values, the recommended value for R2 should be lower than 100kΩ, in order to set the divider current at 5μA or
higher. From that, the value of the resistor connected between VOUT and FB, R1, depending on the needed
output voltage (VOUT), can be calculated using Equation 8:
æV
ö
R1 = R2 × ç OUT - 1÷
è VFB
ø
(8)
A small capacitor C3=10pF, in parallel with R1 needs to be placed when using the Power Save Mode, to improve
considerably the output voltage ripple.
Submit Documentation Feedback
Copyright © 2012, Texas Instruments Incorporated
Product Folder Links: TPS63036
17
TPS63036
SLVSB76 – AUGUST 2012
www.ti.com
LAYOUT CONSIDERATIONS
For all switching power supplies, the layout is an important step in the design, especially at high peak currents
and high switching frequencies. If the layout is not carefully done, the regulator could show stability problems as
well as EMI problems. Therefore, use wide and short traces for the main current path and for the ground tracks.
The input capacitor, output capacitor, and the inductor should be placed as close as possible to the IC.
The feedback divider should be placed as close as possible to the ground pin of the IC.
THERMAL INFORMATION
Implementation of integrated circuits in low-profile and fine-pitch surface-mount packages typically requires
special attention to power dissipation. Many system-dependent issues such as thermal coupling, airflow, added
heat sinks and convection surfaces, and the presence of other heat-generating components affect the powerdissipation limits of a given component.
Three basic approaches for enhancing thermal performance are listed below.
1. Improving the power dissipation capability of the PCB design
2. Improving the thermal coupling of the component to the PCB by soldering all pins to traces as wide as
possible.
3. Introducing airflow in the system
The maximum recommended junction temperature (TJ ) of the TPS63036 device is 125°C. The thermal
resistance of this 8-pin chip-scale package (YFG) is RθJA = 84°C/W, if all pins are soldered. Specified regulator
operation is assured to a maximum ambient temperature TA of 85°C. Therefore, the maximum power dissipation
is about 476 mW, as calculated in Equation 9. More power can be dissipated if the maximum ambient
temperature of the application is lower.
T
*T
J(MAX)
A
P
+
+ 125°C * 85°C + 476 mW
D(MAX)
R
84 °CńW
qJA
(9)
PACKAGE INFORMATION
Package Dimensions
The package dimensions for this YFG package are shown in the table below. See the package drawing at the
end of this data sheet for more details.
Table 4. YFG Package Dimensions
18
Packaged Devices
D
E
TPS63036YFG
1.854 ± 0.03mm
1.076±0.03mm
Submit Documentation Feedback
Copyright © 2012, Texas Instruments Incorporated
Product Folder Links: TPS63036
TPS63036
www.ti.com
SLVSB76 – AUGUST 2012
TYPICAL APPLICATION
L1
1.5µH
VIN
2.3 V to 5V
L1
VIN
VOUT
EN
C1
10µF
VOUT
3.3V/100mA
L2
R1
287kΩ
PS/SYNC
C3
10pF
C2
3X10µF
FB
R2
GND
51.1kΩ
TPS63036
Figure 25. Typical Application Circuit for LCD-Bias
Submit Documentation Feedback
Copyright © 2012, Texas Instruments Incorporated
Product Folder Links: TPS63036
19
PACKAGE OPTION ADDENDUM
www.ti.com
15-Aug-2012
PACKAGING INFORMATION
Orderable Device
Status
(1)
Package Type Package
Drawing
Pins
Package Qty
Eco Plan
(2)
Lead/
Ball Finish
MSL Peak Temp
(3)
Samples
(Requires Login)
TPS63036YFGR
PREVIEW
DSBGA
YFG
8
3000
Green (RoHS
& no Sb/Br)
SNAGCU
Level-1-260C-UNLIM
TPS63036YFGT
PREVIEW
DSBGA
YFG
8
250
Green (RoHS
& no Sb/Br)
SNAGCU
Level-1-260C-UNLIM
(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 OPTION ADDENDUM
www.ti.com
15-Aug-2012
PACKAGING INFORMATION
Orderable Device
Status
(1)
Package Type Package
Drawing
Pins
Package Qty
Eco Plan
(2)
Lead/
Ball Finish
MSL Peak Temp
(3)
Samples
(Requires Login)
TPS63036YFGR
PREVIEW
DSBGA
YFG
8
3000
Green (RoHS
& no Sb/Br)
SNAGCU
Level-1-260C-UNLIM
TPS63036YFGT
PREVIEW
DSBGA
YFG
8
250
Green (RoHS
& no Sb/Br)
SNAGCU
Level-1-260C-UNLIM
(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
IMPORTANT NOTICE
Texas Instruments Incorporated and its subsidiaries (TI) reserve the right to make corrections, enhancements, improvements and other
changes to its semiconductor products and services per JESD46, latest issue, and to discontinue any product or service per JESD48, latest
issue. Buyers should obtain the latest relevant information before placing orders and should verify that such information is current and
complete. All semiconductor products (also referred to herein as “components”) are sold subject to TI’s terms and conditions of sale
supplied at the time of order acknowledgment.
TI warrants performance of its components to the specifications applicable at the time of sale, in accordance with the warranty in TI’s terms
and conditions of sale of semiconductor products. Testing and other quality control techniques are used to the extent TI deems necessary
to support this warranty. Except where mandated by applicable law, testing of all parameters of each component is not necessarily
performed.
TI assumes no liability for applications assistance or the design of Buyers’ products. Buyers are responsible for their products and
applications using TI components. To minimize the risks associated with Buyers’ products and applications, Buyers should provide
adequate design and operating safeguards.
TI does not warrant or represent that any license, either express or implied, is granted under any patent right, copyright, mask work right, or
other intellectual property right relating to any combination, machine, or process in which TI components or services are used. Information
published by TI regarding third-party products or services does not constitute a license to use such products or services or a warranty or
endorsement thereof. Use of such information may require a license from a third party under the patents or other intellectual property of the
third party, or a license from TI under the patents or other intellectual property of TI.
Reproduction of significant portions of TI information in TI data books or data sheets is permissible only if reproduction is without alteration
and is accompanied by all associated warranties, conditions, limitations, and notices. TI is not responsible or liable for such altered
documentation. Information of third parties may be subject to additional restrictions.
Resale of TI components or services with statements different from or beyond the parameters stated by TI for that component or service
voids all express and any implied warranties for the associated TI component or service and is an unfair and deceptive business practice.
TI is not responsible or liable for any such statements.
Buyer acknowledges and agrees that it is solely responsible for compliance with all legal, regulatory and safety-related requirements
concerning its products, and any use of TI components in its applications, notwithstanding any applications-related information or support
that may be provided by TI. Buyer represents and agrees that it has all the necessary expertise to create and implement safeguards which
anticipate dangerous consequences of failures, monitor failures and their consequences, lessen the likelihood of failures that might cause
harm and take appropriate remedial actions. Buyer will fully indemnify TI and its representatives against any damages arising out of the use
of any TI components in safety-critical applications.
In some cases, TI components may be promoted specifically to facilitate safety-related applications. With such components, TI’s goal is to
help enable customers to design and create their own end-product solutions that meet applicable functional safety standards and
requirements. Nonetheless, such components are subject to these terms.
No TI components are authorized for use in FDA Class III (or similar life-critical medical equipment) unless authorized officers of the parties
have executed a special agreement specifically governing such use.
Only those TI components which TI has specifically designated as military grade or “enhanced plastic” are designed and intended for use in
military/aerospace applications or environments. Buyer acknowledges and agrees that any military or aerospace use of TI components
which have not been so designated is solely at the Buyer's risk, and that Buyer is solely responsible for compliance with all legal and
regulatory requirements in connection with such use.
TI has specifically designated certain components which meet ISO/TS16949 requirements, mainly for automotive use. Components which
have not been so designated are neither designed nor intended for automotive use; and TI will not be responsible for any failure of such
components to meet such requirements.
Products
Applications
Audio
www.ti.com/audio
Automotive and Transportation
www.ti.com/automotive
Amplifiers
amplifier.ti.com
Communications and Telecom
www.ti.com/communications
Data Converters
dataconverter.ti.com
Computers and Peripherals
www.ti.com/computers
DLP® Products
www.dlp.com
Consumer Electronics
www.ti.com/consumer-apps
DSP
dsp.ti.com
Energy and Lighting
www.ti.com/energy
Clocks and Timers
www.ti.com/clocks
Industrial
www.ti.com/industrial
Interface
interface.ti.com
Medical
www.ti.com/medical
Logic
logic.ti.com
Security
www.ti.com/security
Power Mgmt
power.ti.com
Space, Avionics and Defense
www.ti.com/space-avionics-defense
Microcontrollers
microcontroller.ti.com
Video and Imaging
www.ti.com/video
RFID
www.ti-rfid.com
OMAP Applications Processors
www.ti.com/omap
TI E2E Community
e2e.ti.com
Wireless Connectivity
www.ti.com/wirelessconnectivity
Mailing Address: Texas Instruments, Post Office Box 655303, Dallas, Texas 75265
Copyright © 2012, Texas Instruments Incorporated