TPS65137
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SLVS929A – MAY 2010 – REVISED OCTOBER 2012
200mA Dual Output AMOLED Display Power
Check for Samples: TPS65137
FEATURES
DESCRIPTION
•
•
•
•
•
•
•
The TPS65137 is designed to provide best in class
picture quality for AMOLED displays (Active Matrix
Organic Light Emitting Diode) requiring positive and
negative voltage supply rails. With its wide input
voltage range the device is ideally suited for
AMOLED displays, which are used in mobile phones
and smart phones. With this device the input voltage
can be higher than the positive output voltage and
still maintains accurate regulation of VPOS. Using the
digital control pin (CTRL) allows adjusting the
negative output voltage in digital steps. The
TPS65137 uses a novel technology enabling
excellent line and load regulation with minimum
output voltage ripple by using a LDO post regulator
for VPOS. This is required avoiding disturbance of the
AMOLED display due to input voltage transients
occurring during transmit periods in mobile phones.
1
•
•
•
•
•
•
2.3 V to 5.5 V Input Voltage Range
1% Output Voltage Accuracy VPOS
Excellent Line Transient Regulation
Low Noise Operation
200 mA Output Current
Fixed 4.63 V Positive Output Voltage
Digitally Programmable Negative Output
Voltage Down to –5.23V
–4.93V Default Value for VNEG
Advanced Power Save Mode
Short Circuit Protection
Thermal Shutdown
TPS65137A High impedance output in
shutdown
3×3 mm 10 Pin QFN Package
APPLICATIONS
•
Active Matrix OLED Power Supply
TYPICAL APPLICATION
L1
4.7mH
VPOS
4.63V/200mA
VIN
2.3V to 5.5V
C2
2.2mF
C1
4.7mF
Enable and
Digital OUTN
Adjustment
VNEG
-4.93V/200mA
C6
4.7mF
C5
4.7mF
C4
100nF
L2
4.7mH
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 © 2010–2012, Texas Instruments Incorporated
TPS65137
SLVS929A – MAY 2010 – REVISED OCTOBER 2012
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This integrated circuit can be damaged by ESD. Texas Instruments recommends that all integrated circuits be handled with
appropriate precautions. Failure to observe proper handling and installation procedures can cause damage.
ESD damage can range from subtle performance degradation to complete device failure. Precision integrated circuits may be more
susceptible to damage because very small parametric changes could cause the device not to meet its published specifications.
ORDERING INFORMATION (1)
(1)
(2)
(2)
TA
ORDERING P/N
PACKAGE MARKING
–40°C to 85°C
TPS65137A
PTTI
For the most current package and ordering information, see the
Package Option Addendum at the end of this document, or visit the
device product folder on ti.com.
Contact the factory for the availability of the TPS65137 with output
voltage discharge function.
ABSOLUTE MAXIMUM RATINGS
over operating free-air temperature range (unless otherwise noted) (1)
VALUE
Input voltage range (2)
ESD rating
UNIT
MIN
MAX
VIN
–0.3
7.0
CTRL, SWP, OUTP
–0.3
7.0
SWP, OUTP
–0.3
7.0
OUTN
+0.3
–5.5
CB
–0.3
7.0
CT
–0.3
3.6
HBM
V
2
kV
MM
200
V
CDM
500
V
Continuous total power dissipation
See Thermal
Information Table
Operating junction temperature range
TJ
–40
150
°C
Operating ambient temperature range
TA
–40
85
°C
Storage temperature range
Tstg
–65
150
°C
(1)
(2)
2
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.
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THERMAL INFORMATION
TPS65137
THERMAL METRIC (1)
DSC
UNITS
10
Junction-to-ambient thermal resistance (2)
θJA
56.5
(3)
θJC(top)
Junction-to-case(top) thermal resistance
θJB
Junction-to-board thermal resistance
ψJT
Junction-to-top characterization parameter
ψJB
Junction-to-board characterization parameter
θJC(bottom)
(1)
(2)
(3)
(4)
(5)
(6)
(7)
65.8
(4)
25.2
(5)
Junction-to-case(bottom) thermal resistance
1.0
(6)
°C/W
17.9
(7)
2.5
For more information about traditional and new thermal metrics, see the IC Package Thermal Metrics application report, SPRA953.
The junction-to-ambient thermal resistance under natural convection is obtained in a simulation on a JEDEC-standard, high-K board, as
specified in JESD51-7, in an environment described in JESD51-2a.
The junction-to-case (top) thermal resistance is obtained by simulating a cold plate test on the package top. No specific JEDECstandard test exists, but a close description can be found in the ANSI SEMI standard G30-88.
The junction-to-board thermal resistance is obtained by simulating in an environment with a ring cold plate fixture to control the PCB
temperature, as described in JESD51-8.
The junction-to-top characterization parameter, ψJT, estimates the junction temperature of a device in a real system and is extracted
from the simulation data for obtaining θJA, using a procedure described in JESD51-2a (sections 6 and 7).
The junction-to-board characterization parameter, ψJB, estimates the junction temperature of a device in a real system and is extracted
from the simulation data for obtaining θJA , using a procedure described in JESD51-2a (sections 6 and 7).
The junction-to-case (bottom) thermal resistance is obtained by simulating a cold plate test on the exposed (power) pad. No specific
JEDEC standard test exists, but a close description can be found in the ANSI SEMI standard G30-88.
Spacer
RECOMMENDED OPERATING CONDITIONS (1)
MIN
NOM
MAX
UNIT
VIN
Input voltage range
2.3
5.5
V
TA
Operating ambient temperature
–40
+85
°C
TJ
Operating junction temperature
–40
+125
°C
(1)
Refer to application section for further information.
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ELECTRICAL CHARACTERISTICS
VIN = 3.5V, EN = VIN, OUTP = 4.63V, OUTN = –4.93V, TA = –40°C to 85°C, typical values are at TA = 25°C (unless otherwise
noted)
PARAMETER
TEST CONDITIONS
MIN
TYP
MAX
UNIT
SUPPLY CURRENT
VIN
Input voltage range
IQ
Operating quiescent current into Vin
ISD
Shutdown current into Vin
UVLO
Under-voltage lockout threshold
fs
Switching frequency
2.3
5.5
0.1
1.0
VIN falling
2.0
VIN rising
2.3
Iout = 100 mA
Thermal shutdown
Thermal shutdown hysteresis
V
μA
400
μA
V
1.6
MHz
145
°C
10
°C
OUTPUT OUTP
VPOS
Positive output voltage regulation
IoutP
Output current OUTP
VIN = 2.3V to 5.5V, Iload=0mA to 150mA
–1%
4.63
200
VIN = 3.7 V, Isw = 200 mA
300
SWP MOSFET rectifier on-resistance
VIN = 3.7 V, Isw = 200 mA
350
Ileak
Leakage current into OUTP
CTRL = GND, VOUTP= 4.6V; TPS65137A
ISWP
SWP switch current limit
VIN = 2.9 V
Vdrop
LDO Dropout voltage
Iout = 100 mA
17
0.9
Line regulation
Load regulation
V
mA
SWP MOSFET on-resistance
RDS(ON)
1%
mΩ
25
uA
1.1
A
300
mV
0
%/V
0.001
%/mA
OUTPUT OUTN
VNEG
Negative output voltage range
VNEG
Negative output voltage regulation
VIN = 2.3V to 5.5V, Iload = 0mA to 150mA;
Valid for all voltage steps
SWN MOSFET on-resistance
VIN = 3.7 V, Isw = 200 mA
400
SWN MOSFET rectifier on-resistance
VIN = 3.7 V, Isw = 200 mA
550
ILKG
Leakage current out of OUTN
CTRL = GND, VOUTN=-5.2V; TPS65137A
ISWN
SWN switch current limit
VIN = 2.9 V
RDS(ON)
–2.2
–5.2
V
–100
+100
mV
19
1.1
Line regulation
mΩ
30
1.35
A
0
Load regulation
μA
%/V
0.001
%/mA
CTRL INTERFACE
VH
Logic high-level voltage
VL
Logic low-level voltage
R
Pull down resistor
tinit
Initialization time
tss
Softstart time
toff
Shutdown time period
80
μs
thigh
Pulse high level time period
2
10
25
μs
tlow
Pulse low level time period
2
10
25
μs
tstore
Data storage/accept time period
tset
OUTN transition time
RT
CT pin output impedance
4
1.2
150
V
0.4
V
200
860
kΩ
300
400
1
30
30
CT = 100 nF
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80
20
150
250
μs
ms
μs
ms
500
kΩ
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DEVICE INFORMATION
10 PIN TQFN PACKAGE
(TOP VIEW
1
SWN
2
OUTN
3
CTRL
4
CT
5
10 PGND
Exposed
Thermal Die
VIN
9 SWP
8 CB
7 OUTP
6 GND
Pin Functions
PIN
NAME
DESCRIPTION
NO.
I/O
VIN
1
I
Input supply
CT
5
O
Sets the settling time for the voltage on Vneg when programmed to a new value
CB
8
O
Internal boost converter bypass capacitor
GND
6
Analog ground
PGND
10
Power Ground
SWN
2
Switch pin of the negative buck boost converter
OUTN
3
O
Output of negative buck boost converter
OUTP
7
O
Output of the boost converter
CTRL
4
I
Combined enable and output voltage program pin
SWP
9
Exposed thermal die
Switch pin of the boost converter
Connect this pad to analog GND.
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TYPICAL CHARACTERISTICS
TABLE OF GRAPHS
FIGURE
Efficiency versus Output current
Figure 1
Efficiency versus Input voltage
Figure 2
Efficiency versus Negative voltage
Figure 3
Negative output voltage programming
Negative output voltage programming
Figure 4
Device enabled (CTRL = 400µs high), programmed to –3.0V
Figure 5
Light load current operation
Figure 6
Nominal load current operation
VIN = 3.7V
Figure 7
Nominal load current operation
VIN = 4.5V
Figure 8
Line transient response
150mA
Figure 9
Line transient response
100mA
Figure 10
Startup
Figure 11
Shutdown
Figure 12
Short circuit
Figure 13
100
90
100
VPOS = 4.63 V,
VNEG = -4.93 V,
VIN = 4.5 V
L = 4.7 mH TDK VLF4012
VPOS = 4.63 V,
VNEG = -4.93 V,
95
L = 4.7 mH TDK VLF4012
VIN = 4.2 V
90
IO = 140 mA
VIN = 2.5 V
VIN = 3 V
70
Efficiency - %
Efficiency - %
80
VIN = 3.7 V
60
IO = 100 mA
85
80
75
IO = 10 mA
70
IO = 50 mA
50
65
40
0
50
100
150
200
IO - Output Current - mA
250
300
60
2
Figure 1. EFFICIENCY
6
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2.5
3
3.5
4
4.5
5
VIN - Input Voltage - V
Figure 2. EFFICIENCY
5.5
6
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100
95
VIN = 3.7 V,
VPOS = 4.63 V,
IO = 100 mA,
VIN = 3.6 V,
VPOS = 4.63 V,
Efficiency - %
L = 4.7 mH TDK VLF4012
90
VPOS
2 V/div
85
VNEG
2 V/div
VNEG = -4.93 V to -3 V,
IO = 50 mA,
CT = 47 nF
80
10 ms/div
75
70
-5.5
-5
-4.5
-4
-3.5
-3
VNEG - V
Figure 3. EFFICIENCY
-2.5
-2
Figure 4. NEGATIVE OUTPUT VOLTAGE PROGRAMMING
VIN = 3.6 V,
VPOS = 4.63 V,
VPOS
2 V/div
VNEG
2 V/div
VCTRL
2 V/div
VNEG = -4.93 V to -3 V,
RLoad = 600 W,
CT = 47 nF
VPOS
20 mV/div
Vswpos
2 V/div
Vswneg
10 V/div
Positive
Inductor
current
200 mA/div
VIN = 3.7 V,
VPOS = 4.63 V,
VNEG = -4.93 V,
IO = 20 mA
200 ms/div
Figure 5. NEGATIVE OUTPUT VOLTAGE PROGRAMMING
(Device enabled (CTRL = 400µs high),
programmed to –3.0V)
250 ns/div
Figure 6. LIGHT LOAD CURRENT OPERATION
VPOS
20 mV/div
VPOS
20 mV/div
Vswpos
2 V/div
Vswpos
2 V/div
Vswneg
10 V/div
Vswneg
10 V/div
Positive
Inductor
current
200 mA/div
VIN = 3.7 V,
VPOS = 4.63 V,
VNEG = -4.93 V,
IO = 150 mA
250 ns/div
Figure 7. NOMINAL LOAD CURRENT OPERATION
(VIN = 3.7V)
Positive
Inductor
current
200 mA/div
VIN = 4.5 V,
VPOS = 4.63 V,
VNEG = -4.93 V
IO = 150 mA
250 ns/div
Figure 8. NOMINAL LOAD CURRENT OPERATION
(VIN = 4.5V)
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VIN = 2.9 V to 3.4 V/50 ms, VPOS = 4.63 V,
VIN = 2.9 V to 3.4 V/50 ms, VPOS = 4.63 V,
VIN
1 V/div
VNEG = -4.93 V, IO = 150 mA
VIN
1 V/div
VPOS
20 mV/div
VPOS
20 mV/div
VNEG
50 mV/div
VNEG
50 mV/div
100 ms/div
Figure 9. LINE TRANSIENT RESPONSE (150mA)
VNEG = -4.93 V, IO = 100 mA
100 ms/div
Figure 10. LINE TRANSIENT RESPONSE (100mA)
VIN = 3.7 V,
VPOS = 4.63 V,
VNEG = -4.93 V,
RLoad = 600 W
VNEG
2 V/div
VPOS
2 V/div
VPOS
2 V/div
VIN
2 V/div
VNEG
2 V/div
VIN
2 V/div
Iin
100 mA/div
VIN = 3.8 V,
VPOS = 4.63 V,
VNEG = -4.93 V,
RLoad = Open
50 ms/div
Figure 12. SHUTDOWN
200 ms/div
Figure 11. STARTUP
VIN = 3.7 V,
VPOS = 4.63 V,
VNEG = -4.93 V,
VPOS shorted
VNEG
2 V/div
VNEG
VPOS
2 V/div
Iout
100 mA/div
20 ms/div
Figure 13. SHORT CIRCUIT
8
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FUNCTIONAL BLOCK DIAGRAM
CB
SWP
GND
Bias
OUTP
LDO
VIN
Gate Drive
SS
SS
PGND
Voltage
Controlled
Oscillator
VCO
Softstart
generation
PWM /
PFM
Control
SS
Current
Sense /
Softstart
+
+
Current
Sense /
Softstart
SS
PWM /
PFM
Control
Vref
+
CT
+
5 Bit
DAC
Gate Drive
Digital
Interface
OUTN
CTRL
GND
SWN
PGND
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DETAILED DESCRIPTION
The TPS65137 consists of a boost converter using a LDO as post regulator. The output voltage of the boost
converter is regulated to operate the internal LDO above its dropout voltage maintaining best line and load
regulation of OUTP. The internal LDO disconnects OUTP during shutdown and allows regulation of the output
when the input voltage is higher than OUTP. The LDO minimizes the output voltage ripple of OUTP. The
negative output uses a buck boost converter topology operating in DCM (Discontinuous Conduction Mode)
providing superior line regulation. In order to adjust the output voltage of the negative converter a digital interface
can be used to program the output voltage. To achieve high efficiency over the entire load current range the
device reduces the switching frequency with the load current using its internal voltage controlled oscillator (VCO).
Since the boost converter output CB is post regulated by the integrated LDO (Low Dropout Regulator) the output
voltage ripple is minimized and the line transient response is at its best. Because of this topology the operation
mode of the boost converter has minimum effect on the output voltage ripple observed on OUTP. The boost
converter, as well as the negative converter operate in peak current mode using the VCO (Voltage Controlled
Oscillator) while operating in DCM (Discontinuous Conduction Mode). When entering CCM (Continuous
Conduction Mode) the converter operates in peak current control using fixed off time control.
POWER SAVE MODE OPERATION
In order to maintain high efficiency over the entire load current range the converter reduces its switching
frequency as the load current decreases. To maintain a controlled switching frequency a voltage controlled
oscillator (VCO) is used.
SOFT START AND SHORT CIRCUIT PROTECTION
The device has a soft-start implemented limiting inrush current during turn on. The device is also protected
against short circuits of the outputs to ground or when the outputs shorted together. This is implemented with two
output voltage thresholds determining the device switch current limit and LDO operation shown in Figure 14.
Voutp Iswlim= full current limit
Boost starts
LDO off
Voutn Isw lim= 120 mA
Voutp Isw lim = 220 mA
LDO = 100 mA current limit
Voutn Isw lim = 120 mA
Voutn = -0.4 V
LDO = full current limit
Voutn Iswlim= full current limit
Voutp = 3 V
Voutn = -1 V
Figure 14. Soft Start and Short Circuit Thresholds
When the device is enabled pulling CTRL pin high then the boost converter and buck converter starts with
reduced switch current limit. During this period of time the LDO is turned off. As VNEG reaches –0.4V then the
LDO is turned on having a 100mA current limit. The switch current limit of both outputs is increased to 220mA
and 120mA. When VPOS reaches 3V and VNEG reaches –1V, then both outputs operate with full current limit. This
architecture limits the inrush current during start-up and protects the device during short circuits events. When
the positive output is shorted to the negative output then the device cycles between the first and second section
of the start-up sequence. By that, the output current cycles between zero and 100mA. This protects the device
and avoids excessive power dissipation during short circuit conditions. With this architecture the device is able to
start-into full load current once VPOS exceeds 3V and VNEG is lower than –1V.
10
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ENABLE (CTRL pin)
The CTRL pin serves two functions. One is the enable and disable of the device, the other is the output voltage
programming of the device. If the digital interface is not required the CTRL pin can be used as a standard enable
pin for the device. Pulling CTRL high starts the converter operating with its default output voltage on OUTN of
–4.93V.
DIGITAL INTERFACE (CTRL)
The digital interface allows programming the negative output voltage OUTN in digital steps. If the digital output
voltage setting is not required then the CTRL pin can also be used as a standard enable pin. In such a case the
device will come up with its default output voltage of OUTN of –4.93V.
tinit
toff
tss
High
CTRL
Low
Vss
VDD
Figure 15. CTRL Used as a Standard Device Enable
The digital output voltage programming of OUTN is implemented by a simple digital interface with the timing
shown in Figure 16.
tlow
tinit
thigh
tstore
toff
tss
High
CTRL
Low
tset
VSS
VDD
Figure 16. Digital Interface Using CTRL
Once CTRL is pulled high the device will come up with its default voltage of –4.93V. The TPS65137 has a 5 bit
DAC implemented with the correspondent output voltage as given in Table 1. The interface counts the rising
edges applied to CTRL pin once the device is enable. For example with the timing diagram shown in Figure 16,
OUTN is programmed to –4.93V since 4 rising edges are applied. Other output voltages are programmed
according to Table 1.
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Table 1. Programming Table for OUTN
BIT/RISING EDGES
OUTN (Vss)
DAC VALUE
BIT/RISING EDGES
OUTN(Vss)
DAC VALUE
Default
–4.93 V
00000
16
–3.7 V
10000
1
–5.23 V
00001
17
–3.62 V
10001
2
–5.13 V
00010
18
–3.52 V
10010
3
–5.03 V
00011
19
–3.42 V
10011
4
–4.93 V
00100
20
–3.32 V
10100
5
–4.83 V
00101
21
–3.22 V
10101
6
–4.73 V
00110
22
–3.12 V
10110
7
–4.63 V
00111
23
–3.02 V
10111
8
–4.53 V
01000
24
–2.92 V
11000
9
–4.43 V
01001
25
–2.82 V
11001
10
–4.33 V
01010
26
–2.72 V
11010
11
–4.23 V
01011
27
–2.62 V
11011
12
–4.13 V
01100
28
–2.52 V
11100
13
–4.03 V
01101
29
–2.42 V
11101
14
–3.93 V
01110
30
–2.31 V
11110
15
–3.82 V
01111
31
–2.21 V
11111
Vneg Programming Transition Time tset for OUTN (CT)
The TPS65137 allows setting the transition time tset using an external capacitor connected to pin CT. The
transition time is the time period required to move OUTN from one voltage level to the next programmed voltage
level. When the CT pin is left open then the shortest possible transition time is programmed. When connecting a
capacitor to the CT pin then the transition time is given by the R-C time constant. This is given by the output
impedance of the CT pin of typically 250kΩ and the external capacitance. Within one τ the output voltage OUTN
has reached 70% of its programmed value. An example is given when using 100nF for CT.
τ ≈ tset70% = 250 kΩ × CT = 250 kΩ × 100 nF = 25 mS
INPUT CAPACITOR SELECTION
The device typically requires a 4.7μF ceramic input capacitor. Larger values can be used to lower the input
voltage ripple.
Table 2. Input Capacitor Selection
CAPACITOR
COMPONENT SUPPLIER
SIZE
4.7 μF/10 V
Taiyo Yuden LMK107BJ475
0603
10 μF/10 V
Taiyo Yuden LMK212BJ106
0805
10 μF/6.3 V
Taiyo Yuden JMK107BJ106
0603
BOOST CONVERTER DESIGN CONSIDERATION, Vpos
The positive output consists of a boost converter using a LDO as post regulator. The maximum output current is
limited by the minimum current limit of the LDO, of 200mA. The component values and output current are
calculated at maximum load current in continuous conduction operation. The typical switching frequency during
this operation mode is 1.4MHz.
The boost converter duty cycle is:
D=1 -
VIN ´ η
VPOS
(1)
To calculate the duty cycle, a good estimation for the efficiency, η, is 75% or it can be taken out of the typical
curve in Figure 1. In order to calculate the maximum output current of the boost converter for a certain input
voltage, the following formula is used:
12
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æ
VIN ´ D ö
Iout = (1 - D )ç Isw ÷
2 ´ ¦s ´ L ø
è
(2)
The maximum output current is given at the highest switching frequency of typically 1.4MHz and minimum switch
current limit of 0.9A. Equation 3 is used to calculate the switch peak current.
Iswpeak =
VIN ´ D
Iout
+
2 ´ ¦s ´ L 1 - D
(3)
The inductor needs to be rated for this switch peak current to avoid inductor saturation.
The boost converter output capacitor is connected to pin CB and a 4.7µF capacitor is sufficient. A 2.2µF
capacitor is used on the output VPOS, which is the output of the internal low dropout regulator (LDO).
Table 3. Output Capacitor Selection
CAPACITOR
COMPONENT SUPPLIER
SIZE
4.7 μF/10 V
Taiyo Yuden LMK107BJ475
0603
2.2 μF/10 V
Taiyo Yuden LMK107BJ225
0603
NEGATIVE BUCK BOOST CONVERTER DESIGN CONSIDERATION, Vneg
The negative output is generated with a buck boost converter. The component values and output current are
calculated at maximum load current in continuous conduction operation. The typical switching frequency during
this operation mode is 1.4MHz.
The buck boost converter duty cycle is:
D=
VNEG
VIN ´ η + VNEG
(4)
To calculate the duty cycle a good estimation for the efficiency, η, is 75% or it can be taken out of the typical
curve in Figure 1. In order to calculate the maximum output current of the buck boost converter for a certain input
voltage, the following formula is used:
æ
VIN ´ D ö
Iout = (1 - D )ç Isw ÷
2 ´ ¦s ´ L ø
è
(5)
The maximum output current is given at the highest switching frequency of typically 1.4MHz and minimum switch
current limit of 1.1A. Equation 6 is used to calculate the switch peak current.
Iswpeak =
VIN ´ D
Iout
+
2 ´ ¦s ´ L 1 - D
(6)
The inductor needs to be rated for this switch peak current to avoid inductor saturation. Refer to Table 4 for
possible inductors for this application. A 4.7μF output capacitor is used on the output VNEG. Larger capacitor
values can be used to minimize the output voltage ripple. Refer to Table 3 for output capacitor selection.
INDUCTOR SELECTION
The device is optimized to operate with 4.7uH inductors. Different inductor values will change the converter
efficiency and output voltage ripple. A 2.2uH inductor is also a possible solution. Any other inductor values will
degrade device performance and stability which is not recommended for this device.
Table 4. Inductor Selection
INDUCTOR VALUE
COMPONENT
SUPPLIER
DIMENSIONS in mm
Isat/DCR
4.7 μH
TDK VLF4012
3.7 × 3.5 × 1.2
1.1A/140mΩ
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Product Folder Links: TPS65137
13
TPS65137
SLVS929A – MAY 2010 – REVISED OCTOBER 2012
www.ti.com
APPLICATION INFORMATION
PCB LAYOUT
The layout for his device is important to keep the output voltage ripple and output voltage accuracy as low and
accurate as possible. The following layout guidelines apply for this device:
• Keep the switch note pad for the boost converter and inverter switch as small as possible to avoid coupling
into the output.
• The ground connection for the inductor of the negative converter needs to be as wide as possible to avoid
noise generated by inductor ground currents.
• The ground connection of the timing capacitor on pin CT needs to be isolated and directly routed to the GND
pin of the device. This is important to avoid noise being coupled into the error amplifier which is internally
connected to the CT pin.
• Having the ground connection of the boost converter output capacitor and LDO output capacitor in a close
connection to the device ground and power pad connection achieves best load regulation.
14
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Copyright © 2010–2012, Texas Instruments Incorporated
Product Folder Links: TPS65137
TPS65137
www.ti.com
SLVS929A – MAY 2010 – REVISED OCTOBER 2012
REVISION HISTORY
Changes from Original (May 2010) to Revision A
Page
•
Changed Features 6, 7 and 8 from 4.6V to 4.63V, -5.2V to -5.23V and -4.9V to -4.93V ..................................................... 1
•
Changed TYPICAL APPLICATION VPOS from 4.6V/200mA to 4.63V/200mA ...................................................................... 1
•
Changed ELECTRICAL CHARACTERISTICS conditions from OUTP=4.6V to OUTP=4.63V and OUTN= -4.9V to 4.93V ..................................................................................................................................................................................... 4
•
Changed ELECTRICAL CHARACTERISTICS OUTPUT OUTP VPOS, TYP column from 4.6 to 4.63 ................................. 4
•
Changed VPOS from 4.6V to 4.63V and VNEG from -4.9V -4.93V in graphs .......................................................................... 6
•
Changed Figure 9 waveform ................................................................................................................................................ 7
•
Changed Figure 10 waveform .............................................................................................................................................. 7
•
Changed -4.9V. to -4.93V in Digital Interface (CTRL) section ............................................................................................ 11
•
Changed values in Table 1 ................................................................................................................................................. 12
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Product Folder Links: TPS65137
15
PACKAGE OPTION ADDENDUM
www.ti.com
10-Dec-2020
PACKAGING INFORMATION
Orderable Device
Status
(1)
Package Type Package Pins Package
Drawing
Qty
Eco Plan
(2)
Lead finish/
Ball material
MSL Peak Temp
Op Temp (°C)
Device Marking
(3)
(4/5)
(6)
TPS65137ADSCR
ACTIVE
WSON
DSC
10
3000
RoHS & Green
NIPDAU
Level-2-260C-1 YEAR
-40 to 85
PTTI
(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)
RoHS: TI defines "RoHS" to mean semiconductor products that are compliant with the current EU RoHS requirements for all 10 RoHS substances, including the requirement that RoHS substance
do not exceed 0.1% by weight in homogeneous materials. Where designed to be soldered at high temperatures, "RoHS" products are suitable for use in specified lead-free processes. TI may
reference these types of products as "Pb-Free".
RoHS Exempt: TI defines "RoHS Exempt" to mean products that contain lead but are compliant with EU RoHS pursuant to a specific EU RoHS exemption.
Green: TI defines "Green" to mean the content of Chlorine (Cl) and Bromine (Br) based flame retardants meet JS709B low halogen requirements of
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