TI TPS53355DQPT

TPS53355
SLUSAE5 – AUGUST 2011
www.ti.com
High-Efficiency 30-A Synchronous Buck Converter with Eco-mode™
Check for Samples: TPS53355
FEATURES
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96% Maximum Efficiency
Conversion Input Voltage Range: 3 V to 15 V
VDD Input Voltage Range: 4.5 V to 25 V
Output Voltage Range: 0.6 V to 5.5 V
5-V LDO Output
Supports Single Rail Input
Integrated Power MOSFETs with 30-A of
Continuous Output Current
Auto-Skip Eco-mode™ for Light-Load
Efficiency
<10 μA Shut Down Current
D-CAP™ Mode with Fast Transient Response
Selectable Switching Frequency from 250 kHz
to 1 MHz with External Resistor
Selectable Auto-Skip or PWM-Only Operation
Built-in 1% 0.6-V Reference.
0.7-ms, 1.4-ms, 2.8-ms and 5.6-ms Selectable
Internal Voltage Servo Soft-Start
Integrated Boost Switch
Pre-Charged Start-up Capability
Adjustable Overcurrent Limit with Thermal
Compensation
Overvoltage, Undervoltage, UVLO and
Over-Temperature Protection
Supports All Ceramic Output Capacitors
•
Open-Drain Power Good Indication
Incorporates NexFET™ Power Block
Technology
22-pin QFN Package with PowerPAD™
APPLICATIONS
•
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Server/Storage
Workstations and Desktops
Telecommunications Infrastructure
DESCRIPTION
TPS53355 is a D-CAP™ mode, 30-A synchronous
switcher with integrated MOSFETs. It is designed for
ease of use, low external component count, and
space-conscious power systems.
This device features 5 mΩ/2.0 mΩ integrated
MOSFETs, accurate 1%, 0.6-V reference, and
integrated boost switch. A sample of competitive
features include: 3-V to 15-V wide conversion input
voltage range, very low external component count,
D-CAP™ mode control for super fast transient,
auto-skip mode operation, internal soft-start control,
selectable frequency, and no need for compensation.
The conversion input voltage ranges from 3 V to
15 V, the supply voltage range is from 4.5 V to 25 V,
and the output voltage range is from 0.6 V to 5.5 V.
The device is available in 5 mm x 6 mm, 22-pin QFN
package and is specified from –40°C to 85°C.
TYPICAL APPLICATION
VVDD
21
20
19
18
17
16
15
14
13
TRIP
MODE
VDD
VREG
VIN
VIN
VIN
VIN
VIN
EN
PGOOD
VBST
N/C
LL
LL
LL
LL
LL
LL
GND
VFB
TPS53355
12
VIN
22
RF
VIN
1
2
3
4
5
6
7
8
9
10
11
VREG
VOUT
PGOOD
EN
UDG-11001
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.
Eco-mode, NexFET, PowerPAD are trademarks 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 © 2011, Texas Instruments Incorporated
TPS53355
SLUSAE5 – AUGUST 2011
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.
ORDERING INFORMATION
TA
PACKAGE
–40°C to 85°C
Plastic QFN
(DQP)
ORDERING PART
NUMBER
TPS53355DQPR
TPS53355DQPT
PINS
22
OUTPUT SUPPLY
MINIMUM
QUANTITY
Tape and reel
2500
Mini reel
250
ECO PLAN
Green (RoHS and no
Pb/Br)
ABSOLUTE MAXIMUM RATINGS (1)
VALUE
Input voltage range
MIN
MAX
VIN (main supply)
–0.3
25
VDD
–0.3
28
VBST
–0.3
32
VBST(with respect to LL)
–0.3
7
EN, TRIP, VFB, RF, MODE
–0.3
7
–2
25
LL
Output voltage range
Source/Sink current
DC
–7
27
PGOOD, VREG
Pulse < 20ns, E=5 μJ
–0.3
7
GND
–0.3
0.3
VBST
50
–40
85
Storage temperature range, Tstg
–55
150
Junction temperature range, TJ
–40
150
Lead temperature 1,6 mm (1/16 inch) from case for 10 seconds
V
V
mA
Operating free-air temperature, TA
(1)
UNIT
˚C
300
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.
THERMAL INFORMATION
THERMAL METRIC (1)
TPS53355
DQP (22 PINS)
θJA
Junction-to-ambient thermal resistance
27.2
θJCtop
Junction-to-case (top) thermal resistance
12.1
θJB
Junction-to-board thermal resistance
5.9
ψJT
Junction-to-top characterization parameter
0.8
ψJB
Junction-to-board characterization parameter
5.8
θJCbot
Junction-to-case (bottom) thermal resistance
1.2
(1)
2
UNITS
°C/W
For more information about traditional and new thermal metrics, see the IC Package Thermal Metrics application report, SPRA953.
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RECOMMENDED OPERATING CONDITIONS
over operating free-air temperature range (unless otherwise noted)
VALUE
VIN (main supply)
Input voltage range
MAX
3
15
VDD
4.5
25
VBST
4.5
28
VBST(with respect to LL)
EN, TRIP, VFB, RF, MODE
Output voltage range
MIN
LL
PGOOD, VREG
Junction temperature range, TJ
4.5
6.5
–0.1
6.5
–1
22
–0.1
6.5
–40
125
UNIT
V
V
°C
ELECTRICAL CHARACTERISTICS
Over recommended free-air temperature range, VVDD=12 V (unless otherwise noted)
PARAMETER
CONDITIONS
MIN
TYP
MAX
UNIT
SUPPLY CURRENT
VVIN
VIN pin power conversion input
voltage
VVDD
Supply input voltage
IVIN(leak)
VIN pin leakage current
VEN = 0 V
IVDD
VDD supply current
TA = 25°C, No load, VEN = 5 V, VVFB = 0.630 V
IVDDSDN
VDD shutdown current
TA = 25°C, No load, VEN = 0 V
3
15
4.5
25.0
V
1
µA
590
µA
10
µA
420
V
INTERNAL REFERENCE VOLTAGE
VVFB
VFB regulation voltage
CCM condition (1)
TA = 25°C
VVFB
VFB regulation voltage
0°C ≤ TA ≤ 85°C
–40°C ≤ TA ≤ 85°C
IVFB
VFB input current
0.600
V
0.597
0.600
0.603
0.5952
0.600
0.6048
0.594
0.600
0.606
0.01
0.20
5.00
5.36
VVFB = 0.630 V, TA = 25°C
V
µA
LDO OUTPUT
VVREG
LDO output voltage
0 mA ≤ IVREG ≤ 30 mA
IVREG
LDO output current (1)
Maximum current allowed from LDO
VDO
Low drop out voltage
VVDD = 4.5 V, IVREG = 30 mA
4.77
V
30
mA
230
mV
BOOT STRAP SWITCH
VFBST
Forward voltage
VVREG-VBST, IF = 10 mA, TA = 25°C
IVBSTLK
VBST leakage current
VVBST = 23 V, VSW = 17 V, TA = 25°C
0.1
0.2
V
0.01
1.50
µA
260
400
ns
DUTY AND FREQUENCY CONTROL
tOFF(min)
tON(min)
Minimum off time
TA = 25°C
Minimum on time
VIN = 17 V, VOUT = 0.6 V, RRF = 39 kΩ,
TA = 25 °C (1)
150
35
RMODE = 39 kΩ
0.7
RMODE = 100 kΩ
1.4
RMODE = 200 kΩ
2.8
RMODE = 470 kΩ
5.6
ns
SOFT START
Internal soft-start time from
VOUT = 0 V to 95% of VOUT
tSS
ms
INTERNAL MOSFETS
RDS(on)H
High-side MOSFET on-resistance
TA = 25°C
5.0
mΩ
RDS(on)L
Low-side MOSFET on-resistance
TA = 25°C
2.0
mΩ
(1)
Ensured by design. Not production tested.
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ELECTRICAL CHARACTERISTICS
Over recommended free-air temperature range, VVDD=12 V (unless otherwise noted)
PARAMETER
TEST CONDITIONS
MIN
TYP
MAX
92.5%
95.0%
98.5%
UNIT
POWERGOOD
PG in from lower
VTHPG
PG threshold
PG in from higher
107.5% 110.0% 112.5%
PG hysteresis
RPG
PG transistor on-resistance
tPGDEL
PG delay
Delay for PG in
2.5%
5.0%
7.5%
15
30
55
Ω
0.8
1
1.2
ms
LOGIC THRESHOLD AND SETTING CONDITIONS
VEN
EN Voltage
IEN
EN Input current
Enable
1.8
Disable
0.6
VEN = 5 V
1.0
RRF = 0 Ω to GND, TA = 25°C
fSW
Switching frequency
(1)
200
250
300
RRF = 187 kΩ to GND, TA = 25°C (1)
250
300
350
RRF = 619 kΩ, to GND, TA = 25°C (1)
350
400
450
RRF = Open, TA= 25°C (1)
450
500
550
(1)
580
650
720
RRF = 309 kΩ to VREG, TA = 25°C (1)
670
750
820
RRF = 124 kΩ to VREG, TA = 25°C (1)
770
850
930
880
970
1070
9.4
10.0
10.6
RRF = 866 kΩ to VREG, TA = 25°C
RRF = 0 Ω to VREG, TA = 25°C
(1)
V
µA
kHz
PROTECTION: CURRENT SENSE
ITRIP
TRIP source current
VTRIP = 1 V, TA = 25°C
TCITRIP
TRIP current temperature coeffficient
On the basis of 25°C
VTRIP
Current limit threshold setting range
VTRIP-GND
VOCL
Current limit threshold
VOCLN
Negative current limit threshold
VAZCADJ
Auto zero cross adjustable range
(2)
VTRIP = 2.4 V
4700
0.4
ppm/°C
2.4
68.5
75.0
81.5
7.5
12.5
17.5
VTRIP = 2.4 V
-315
-300
-285
VTRIP = 0.4 V
-58
-50
-42
3
15
VTRIP = 0.4
Positive
µA
V
mV
mV
mV
–15
–3
115%
120%
125%
65%
70%
75%
0.8
1.0
1.2
ms
1.8
2.6
3.2
ms
4.00
4.20
4.33
Negative
PROTECTION: UVP and OVP
VOVP
OVP trip threshold
OVP detect
tOVPDEL
OVP proprogation delay
VFB delay with 50-mV overdrive
VUVP
Output UVP trip threshold
UVP detect
tUVPDEL
Output UVP proprogation delay
tUVPEN
Output UVP enable delay
From enable to UVP workable
µs
1
UVLO
VUVVREG
VREG UVLO threshold
Wake up
Hysteresis
0.25
Shutdown temperature (2)
145
V
THERMAL SHUTDOWN
TSDN
(1)
(2)
4
Thermal shutdown threshold
Hysteresis (2)
10
°C
Not production tested. Test condition is VIN= 12 V, VOUT= 1.1 V, IOUT = 10 A using application circuit shown in Figure 1.
Ensured by design. Not production tested.
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DEVICE INFORMATION
DQP Package
(Top View)
(1)
VFB
1
22
RF
EN
2
21
TRIP
PGOOD
3
20
MODE
VBST
4
19
VDD
N/C
5
18
VREG
LL
6
17
VIN
LL
7
16
VIN
LL
8
15
VIN
LL
9
14
VIN
LL
10
13
VIN
LL
11
12
VIN
GND
PowerPad
TM
N/C = no connection
PIN FUNCTIONS
PIN
NAME
EN
NO.
2
GND
I/O/P (1)
DESCRIPTION
I
Enable pin.Typical turn-on threshold voltage is 1.2 V. Typical turn-off threshold is 0.95 V.
G
Ground and thermal pad of the device. Use proper number of vias to connect to ground plane.
B
Output of converted power. Connect this pin to the output Inductor.
I
Soft-start and Skip/CCM selection. Connect a resistor to select soft-start time using Table 1. The soft-start
time is detected and stored into internal register during start-up.
6
7
8
LL
9
10
11
MODE
20
N/C
5
PGOOD
3
O
Open drain power good flag. Provides 1-ms start-up delay after VFB falls in specified limits. When VFB
goes out of the specified limits PGOOD goes low after a 2-µs delay.
RF
22
I
Switching frequency selection. Connect a resistor to GND or VREG to select switching frequency using
Table 2. The switching frequency is detected and stored during the startup.
TRIP
21
I
No connect.
OCL detection threshold setting pin. ITRIP = 10 µA at room temperature, 4700 ppm/°C current is sourced
and set the OCL trip voltage as follows.
space VOCL=VTRIP/32
(VTRIP ≤ 2.4 V, VOCL ≤ 75 mV)
VBST
4
P
Supply input for high-side FET gate driver (boost terminal). Connect capacitor from this pin to LL node.
Internally connected to VREG via bootstrap MOSFET switch.
VDD
19
P
Controller power supply input. VDD input voltage range is from 4.5 V to 25 V.
VFB
1
I
Output feedback input. Connect this pin to Vout through a resistor divider.
P
Conversion power input. VIN input voltage range is from 3 V to 15 V.
P
5-V low drop out (LDO) output. Supplies the internal analog circuitry and driver circuitry.
12
13
14
VIN
15
16
17
VREG
(1)
18
I=Input, O=Output, B=Bidirectional, P=Supply, G=Ground
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BLOCK DIAGRAM
0.6 V +10/15%
0.6 V –30%
+
UV
PGOOD
+
Delay
Delay
+
0.6 V –5/10%
Ramp
Compensation
Control Logic
+
+20%
+
VFB
VREG
OV
UVP/OVP
Logic
RF
VBST
0.6 V
SS
+
+ PWM
VIN
10 mA
GND
TRIP
tON
OneShot
+
+ OCP
LL
LL
XCON
+
ZC
GND
Control
Logic
GND
SS
FCCM/
Skip
Decode
MODE
EN
Ÿ
Ÿ
Ÿ
Ÿ
Ÿ
+
On/Off time
Minimum On/Off
Light load
OVP/UVP
FCCM/Skip
VDDOK
LL
Fault
Shutdown
VREG
LDO
+
VDD
4.2 V/
3.95 V
Enable
1.2 V/0.95 V
EN
+
THOK
145°C/
135°C
TPS53355
UDG-11003
6
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APPLICATION CIRCUIT DIAGRAM
C4
4.7 mF
C3
1 mF
R6
200 kW
VVDD
4.5 V to 25 V
R4
R8
187 kW 100 kW
22
21
20
19
RF
TRIP
MODE
VDD
18
17
VREG VIN
16
15
14
13
12
VIN
VIN
VIN
VIN
VIN
TPS53355
CIN
22 mF
CIN
22 mF
CIN
22 mF
CIN
22 mF
VIN 3 V
to
15 V
GND
VREG
VOUT
L1
0.44 mH
PA0513.441
VFB
EN
1
2
R10
100 kW
PGOOD VBST
3
N/C
LL
LL
LL
LL
LL
LL
5
6
7
8
9
10
11
4
R11
NI
R9
2W
PGOOD
EN
R2
10 kW
COUT
330 mF
C6
NI
C5
0.1 mF
COUT
330 mF
R1
8.25 kW
UDG-11002
Figure 1. Typical Application Circuit Diagram
C4
4.7 mF
C3
1 mF
R6
200 kW
VVDD
4.5 V to 25 V
R4
R8
187 kW 100 kW
22
21
20
19
RF
TRIP
MODE
VDD
18
17
VREG VIN
16
15
14
13
12
VIN
VIN
VIN
VIN
VIN
TPS53355
CIN
22 mF
VFB
EN
1
2
PGOOD VBST
3
N/C
LL
LL
LL
LL
LL
LL
5
6
7
8
9
10
11
4
R9
2W
PGOOD
EN
R2
10 kW
CIN
22 mF
VOUT
R7
3.01 kW
C1
0.1 mF
COUT
4 x 100 mF
Ceramic
R11
NI
C5
0.1 mF
CIN
22 mF
L1
0.44 mH
PA0513.441
GND
VREG
R10
100 kW
CIN
22 mF
VIN 3 V
to
15 V
C6
NI
C2
1 nF
R1 8.06 kW
UDG-11004
Figure 2. Typical Application Circuit Diagram with Ceramic Output Capacitors
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700
7
600
6
500
400
300
200
VEN = 5V
VVDD = 12 V
VVFB = 0.63 V
No Load
100
0
−40 −25 −10
5
20 35 50 65 80
Junction Temperature (°C)
95
VDD Shutdown Current (µA)
VDD Supply Current (µA)
TYPICAL CHARACTERISTICS
5
4
3
2
0
−40 −25 −10
110 125
16
140
14
120
10
8
6
4
5
20 35 50 65 80
Junction Temperature (°C)
95
100
80
60
40
20
2
OVP
UVP
VVDD = 12 V
0
−40 −25 −10
5
20 35 50 65 80
Junction Temperature (°C)
95
0
−40 −25 −10
110 125
Figure 5. TRIP Pin Current vs. Junction Temperature
100
FCCM
Skip Mode
10
VIN = 12 V
VOUT = 1.1 V
fSW = 300 kHz
0.1
1
Output Current (A)
10
100
Switching Frequency (kHz)
Switching Frequency (kHz)
95
110 125
1000
Figure 7. Switching Frequency vs. Output Current
8
5
20 35 50 65 80
Junction Temperature (°C)
Figure 6. OVP/UVP Trip Threshold vs. Junction
Temperature
1000
1
0.01
110 125
Figure 4. VDD Shutdown Current vs. Junction
Temperature
OVP/UVP Trip Threshold (%)
TRIP Pin Current (µA)
Figure 3. VDD Supply Current vs. Junction Temperature
12
VEN = 0 V
VVDD = 12 V
No Load
1
100
FCCM
Skip Mode
10
VIN = 12 V
VOUT = 1.1 V
fSW = 500 kHz
1
0.01
0.1
1
Output Current (A)
10
100
Figure 8. Switching Frequency vs. Output Current
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TYPICAL CHARACTERISTICS (continued)
1000
Switching Frequency (kHz)
Switching Frequency (kHz)
1000
100
10
VIN = 12 V
VOUT = 1.1 V
fSW = 750 kHz
FCCM
Skip Mode
1
0.01
0.1
1
Output Current (A)
10
10
VIN = 12 V
VOUT = 1.1 V
fSW = 1 MHz
FCCM
Skip Mode
100
1
0.01
G001
Figure 9. Switching Frequency vs. Output Current
0.1
1
Output Current (A)
10
100
Figure 10. Switching Frequency vs. Output Current
1500
1.120
fSET = 300 kHz
fSET = 500 kHz
fSET = 750 kHz
fSET = 1 MHz
VIN = 12 V
IOUT = 10 A
1200
fSW = 500 kHz
VIN = 12 V
VOUT = 1.1 V
1.115
1.110
Output Voltage (V)
Switching Frequency (kHz)
100
900
600
1.105
1.100
1.095
1.090
300
1.085
0
0
1
2
3
4
Output Voltage (V)
5
1.080
6
Figure 11. Switching Frequency vs. Output Voltage
Skip Mode
FCCM
0
2
4
6
8 10 12 14 16 18 20 22 24 26 28 30
Output Current (A)
Figure 12. Output Voltage vs. Output Current
1.120
100
fSW = 500 kHz
VIN = 12 V
1.115
90
80
70
Efficiency (%)
Output Voltage (V)
1.110
1.105
1.100
1.095
60
VIN = 12 V
VVDD = 5 V
VOUT = 1.1 V
50
40
30
Skip Mode, fSW = 500 kHz
FCCM, fSW = 500 kHz
Skip Mode, fSW = 300 kHz
FCCM, fSW = 300 kHz
1.090
FCCM, IOUT = 0 A
Skip Mode, IOUT = 0 A
FCCM and Skip Mode, IOUT = 20 A
1.085
1.080
4
6
8
10
12
Input Voltage (V)
14
16
20
10
0
0.01
Figure 13. Output Voltage vs. Input Voltage
0.1
1
Output Current (A)
10
Figure 14. Efficiency vs Output Current
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TYPICAL CHARACTERISTICS
100
95
95
90
90
Efficiency (%)
Efficiency (%)
For VOUT = 5 V, a SC5026-1R0 inductor is used. For 1 ≤ VOUT ≤ 3.3 V, a PA0513.441 inductor is used.
100
85
VOUT = 5.0 V
VOUT = 3.3 V
VOUT = 1.8 V
VOUT = 1.5 V
VOUT = 1.2 V
VOUT = 1.1 V
VOUT = 1.0 V
80
75
70
0
5
10
15
20
Output Current (A)
FCCM
VIN = 12 V
VVDD = 5 V
fSW = 300 kHz
25
85
VOUT = 5.0 V
VOUT = 3.3 V
VOUT = 1.8 V
VOUT = 1.5 V
VOUT = 1.2 V
VOUT = 1.1 V
VOUT = 1.0 V
80
75
70
30
0
100
100
95
95
90
90
85
VOUT = 5.0 V
VOUT = 3.3 V
VOUT = 1.8 V
VOUT = 1.5 V
VOUT = 1.2 V
VOUT = 1.1 V
VOUT = 1.0 V
80
75
70
0
5
10
15
20
Output Current (A)
FCCM
VIN = 12 V
VVDD = 5 V
fSW = 500 kHz
25
VOUT = 5.0 V
VOUT = 3.3 V
VOUT = 1.8 V
VOUT = 1.5 V
VOUT = 1.2 V
VOUT = 1.1 V
VOUT = 1.0 V
80
75
70
30
95
95
90
90
Efficiency (%)
Efficiency (%)
100
85
75
70
0
2
4
6
8
10
12
14
Output Current (A)
FCCM
VIN = 5 V
VVDD = 5 V
fSW = 500 kHz
16
0
5
10
15
20
Output Current (A)
Skip Mode
VIN = 12 V
VVDD = 5 V
fSW = 500 kHz
25
30
18
20
85
80
VOUT = 1.8 V
VOUT = 1.5 V
VOUT = 1.2 V
VOUT = 1.1 V
VOUT = 1.0 V
75
70
0
Figure 19. Efficiency vs Output Current
10
30
Figure 18. Efficiency vs Output Current
100
VOUT = 1.8 V
VOUT = 1.5 V
VOUT = 1.2 V
VOUT = 1.1 V
VOUT = 1.0 V
25
85
Figure 17. Efficiency vs Output Current
80
10
15
20
Output Current (A)
Figure 16. Efficiency vs Output Current
Efficiency (%)
Efficiency (%)
Figure 15. Efficiency vs Output Current
5
Skip Mode
VIN = 12 V
VVDD = 5 V
fSW = 300 kHz
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2
4
6
8
10
12
14
Output Current (A)
Skip Mode
VIN = 5 V
VVDD = 5 V
fSW = 500 kHz
16
18
20
Figure 20. Efficiency vs Output Current
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TYPICAL CHARACTERISTICS
VIN = 12 V
VIN = 12 V
IOUT = 20 A
EN (5 V/div)
EN (5 V/div)
IOUT = 0 A
VOUT (0.5 V/div)
VOUT (0.5 V/div)
0.5 V pre-biased
VREG(5 V/div)
VREG(5 V/div)
PGOOD (5 V/div)
PGOOD (5 V/div)
Time (1 ms/div)
Time (1 ms/div)
Figure 21. Start-Up Waveforms
Figure 22. Pre-Bias Start-Up Waveforms
VIN = 12 V
IOUT = 20 A
EN (5 V/div)
VEN = 5 V
VIN (5 V/div)
VDD = VIN
IOUT = 20 A
VOUT (0.5 V/div)
VOUT (0.5 V/div)
VREG(5 V/div)
VREG(5 V/div)
PGOOD (5 V/div)
PGOOD (5 V/div)
Time (20 ms/div)
Time (2 ms/div)
Figure 23. Shutdown Waveforms
Figure 24. UVLO Start-Up Waveforms
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TYPICAL CHARACTERISTICS (continued)
Skip Mode
VIN = 12 V
IOUT = 0 A
FCCM
VIN = 12 V
IOUT = 0 A
VOUT (20 mV/div)
VOUT (20 mV/div)
LL (5 V/div)
LL (5 V/div)
IL (5 A/div)
IL (5 A/div)
Time (2 ms/div)
Time (1 ms/div)
Figure 25. 1.1-V Output FCCM Mode Steady-State
Operation
Figure 26. 1.1-V Output Skip Mode Steady-State Operation
Skip Mode
VIN = 12 V
VOUT = 1.1 V
Skip Mode
VIN = 12 V
VOUT = 1.1 V
VOUT (20 mV/div)
VOUT (20 mV/div)
LL (5 V/div)
LL (5 V/div)
IL (5 A/div)
IL (5 A/div)
Time (200 ms/div)
Time (200 ms/div)
Figure 27. CCM to DCM Transition Waveforms
12
Figure 28. DCM to CCM Transition Waveforms
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TYPICAL CHARACTERISTICS (continued)
FCCM
VIN = 12 V, VOUT = 1.1 V
Skip Mode
VIN = 12 V, VOUT = 1.1 V
IOUT from 0 A to 10 A, 2.5 A/ms
IOUT from 0 A to 10 A, 2.5 A/ms
VOUT (20 mV/div)
VOUT (20 mV/div)
IOUT (5 A/div)
IOUT (5 A/div)
Time (100 ms/div)
Time (100 ms/div)
Figure 29. FCCM Load Transient
IOUT from 20 A to 25 A
VOUT (1 V/div)
Figure 30. Skip Mode Load Transeint
VOUT (1 V/div)
IOUT 2 A then Short Output
VIN = 12 V
VIN = 12 V
LL (10 V/div)
LL (10 V/div)
IL (10 A/div)
IL (10 A/div)
IOUT (25 A/div)
PGOOD (5 V/div)
Time (10 ms/div)
Time (10 ms/div)
Figure 31. Overcurrent Protection Waveforms
Figure 32. Output Short Circuit Protection Waveforms
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TYPICAL CHARACTERISTICS (continued)
EN (5 V/div)
VOUT (1 V/div)
VIN = 12 V
IOUT = 20 A
PGOOD (5 V/div)
90
90
80
80
70
60
50
40
400 LFM
200 LFM
100 LFM
Natural Convection
30
20
0
5
VIN = 12 V
VOUT = 1.2 V
fSW = 500 kHz
10
15
20
Output Current (A)
25
30
Ambient Temperature (°C)
Ambient Temperature (°C)
Time (1 s/div)
Figure 33. Over-temperature Protection Waveforms
70
60
50
40
400 LFM
200 LFM
100 LFM
Natural Convection
30
20
0
Figure 34. Safe Operating Area
14
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5
VIN = 12 V
VOUT = 5 V
fSW = 500 kHz
10
15
20
Output Current (A)
25
30
Figure 35. Safe Operating Area
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APPLICATION INFORMATION
General Description
The TPS53355 is a high-efficiency, single channel, synchronous buck converter suitable for low output voltage
point-of-load applications in computing and similar digital consumer applications. The device features proprietary
D-CAP™ mode control combined with an adaptive on-time architecture. This combination is ideal for building
modern low duty ratio, ultra-fast load step response DC-DC converters. The output voltage ranges from 0.6 V to
5.5 V. The conversion input voltage range is from 3 V up to 15 V and the VDD bias voltage is from 4.5 V to 25 V.
The D-CAP™ mode uses the equivalent series resistance (ESR) of the output capacitor(s) to sense the device
current . One advantage of this control scheme is that it does not require an external phase compensation
network. This allows a simple design with a low external component count. Eight preset switching frequency
values can be chosen using a resistor connected from the RF pin to ground or VREG. Adaptive on-time control
tracks the preset switching frequency over a wide input and output voltage range while allowing the switching
frequency to increase at the step-up of the load.
The TPS53355 has a MODE pin to select between auto-skip mode and forced continuous conduction mode
(FCCM) for light load conditions. The MODE pin also sets the selectable soft-start time ranging from 0.7 ms to
5.6 ms as shown in Table 1.
Enable, Soft Start, and Mode Selection
When the EN pin voltage rises above the enable threshold voltage (typically 1.2 V), the controller enters its
start-up sequence. The internal LDO regulator starts immediately and regulates to 5 V at the VREG pin. The
controller then uses the first 250 μs to calibrate the switching frequency setting resistance attached to the RF pin
and stores the switching frequency code in internal registers. During this period, the MODE pin also senses the
resistance attached to this pin and determines the soft-start time . Switching is inhibited during this phase. In the
second phase, an internal DAC starts ramping up the reference voltage from 0 V to 0.6 V. Depending on the
MODE pin setting, the ramping up time varies from 0.7 ms to 5.6 ms. Smooth and constant ramp-up of the
output voltage is maintained during start-up regardless of load current.
Table 1. Soft-Start and MODE Settings
MODE SELECTION
Auto Skip
Forced CCM (1)
(1)
ACTION
Pull down to GND
Connect to PGOOD
SOFT-START TIME (ms)
RMODE (kΩ)
0.7
39
1.4
100
2.8
200
5.6
475
0.7
39
1.4
100
2.8
200
5.6
475
Device enters FCCM after the PGOOD pin goes high when MODE is connected to PGOOD through
the resistor RMODE.
After soft-start begins, the MODE pin becomes the input of an internal comparator which determines auto skip or
FCCM mode operation. If MODE voltage is higher than 1.3 V, the converter enters into FCCM mode. Otherwise
it will be in auto skip mode at light load condition. Typically, when FCCM mode is selected, the MODE pin is
connected to PGOOD through the RMODE resistor, so that before PGOOD goes high the converter remains in
auto skip mode.
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Adaptive On-Time D-CAP™ Control and Frequency Selection
The TPS53355 does not have a dedicated oscillator to determine switching frequency. However, the device
operates with pseudo-constant frequency by feed-forwarding the input and output voltages into the on-time
one-shot timer. The adaptive on-time control adjusts the on-time to be inversely proportional to the input voltage
and proportional to the output voltage (tON ∝ VOUT/VIN).
This makes the switching frequency fairly constant in steady state conditions over a wide input voltage range.
The switching frequency is selectable from eight preset values by a resistor connected between the RF pin and
GND or between the RF pin and the VREG pin as shown in Table 2. (Maintaining open resistance sets the
switching frequency to 500 kHz.)
Table 2. Resistor and Switching Frequency
RESISTOR (RRF)
CONNECTIONS
VALUE (kΩ)
CONNECT TO
SWITCHING
FREQUENCY
(fSW)
(kHz)
0
GND
250
187
GND
300
619
GND
400
OPEN
n/a
500
866
VREG
650
309
VREG
750
124
VREG
850
0
VREG
970
The off-time is modulated by a PWM comparator. The VFB node voltage (the mid-point of resistor divider) is
compared to the internal 0.6-V reference voltage added with a ramp signal. When both signals match, the PWM
comparator asserts a set signal to terminate the off time (turn off the low-side MOSFET and turn on high-side
MOSFET). The set signal is valid if the inductor current level is below the OCP threshold, otherwise the off time
is extended until the current level falls below the threshold.
Figure 36 and Figure 37 show two on-time control schemes.
VFB
VFB
VREF
VREF
tON
tON
tOFF
UDG-10208
Figure 36. On-Time Control Without Ramp
Compensation
16
Compensation
Ramp
PWM
PWM
tOFF
UDG-10209
Figure 37. On-Time Control With Ramp
Compensation
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Ramp Signal
The TPS53355 adds a ramp signal to the 0.6-V reference in order to improve jitter performance. As described in
the previous section, the feedback voltage is compared with the reference information to keep the output voltage
in regulation. By adding a small ramp signal to the reference, the signal-to-noise ratio at the onset of a new
switching cycle is improved. Therefore the operation becomes less jittery and more stable. The ramp signal is
controlled to start with –7 mV at the beginning of an on-cycle and becomes 0 mV at the end of an off-cycle in
steady state.
During skip mode operation, under discontinuous conduction mode (DCM), the switching frequency is lower than
the nominal frequency and the off-time is longer than the off-time in CCM. Because of the longer off-time, the
ramp signal extends after crossing 0 mV. However, it is clamped at 3 mV to minimize the DC offset.
Auto-Skip Eco-mode™ Light Load Operation
While the MODE pin is pulled low via RMODE, TPS53355 automatically reduces the switching frequency at light
load conditions to maintain high efficiency. Detailed operation is described as follows. As the output current
decreases from heavy load condition, the inductor current is also reduced and eventually comes to the point that
its rippled valley touches zero level, which is the boundary between continuous conduction and discontinuous
conduction modes. The synchronous MOSFET is turned off when this zero inductor current is detected. As the
load current further decreases, the converter runs into discontinuous conduction mode (DCM). The on-time is
kept almost the same as it was in the continuous conduction mode so that it takes longer time to discharge the
output capacitor with smaller load current to the level of the reference voltage. The transition point to the
light-load operation IOUT(LL) (i.e., the threshold between continuous and discontinuous conduction mode) can be
calculated as shown in Equation 1.
IOUT(LL ) =
(VIN - VOUT )´ VOUT
1
´
2 ´ L ´ fSW
VIN
where
•
ƒSW is the PWM switching frequency
(1)
Switching frequency versus output current in the light load condition is a function of L, VIN and VOUT, but it
decreases almost proportionally to the output current from the IOUT(LL) given in Equation 1. For example, it is 60
kHz at IOUT(LL)/5 if the frequency setting is 300 kHz.
Adaptive Zero Crossing
The TPS53355 has an adaptive zero crossing circuit which performs optimization of the zero inductor current
detection at skip mode operation. This function pursues ideal low-side MOSFET turning off timing and
compensates inherent offset voltage of the Z-C comparator and delay time of the Z-C detection circuit. It
prevents SW-node swing-up caused by too late detection and minimizes diode conduction period caused by too
early detection. As a result, better light load efficiency is delivered.
Forced Continuous Conduction Mode
When the MODE pin is tied to PGOOD through a resistor, the controller keeps continuous conduction mode
(CCM) in light load condition. In this mode, switching frequency is kept almost constant over the entire load
range which is suitable for applications need tight control of the switching frequency at a cost of lower efficiency.
Power-Good
The TPS53355 has power-good output that indicates high when switcher output is within the target. The
power-good function is activated after soft-start has finished. If the output voltage becomes within +10%
and –5% of the target value, internal comparators detect power-good state and the power-good signal becomes
high after a 1-ms internal delay. If the output voltage goes outside of +15% or –10% of the target value, the
power-good signal becomes low after two microsecond (2-μs) internal delay. The power-good output is an open
drain output and must be pulled up externally.
The power-good MOSFET is powered through the VDD pin. VVDD must be >1 V in order to have a valid
power-good logic. It is recommended to pull PGOOD up to VREG (or a voltage divided from VREG) so that the
power-good logic is still valid even without VDD supply.
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Current Sense, Overcurrent and Short Circuit Protection
TPS53355 has cycle-by-cycle overcurrent limiting control. The inductor current is monitored during the OFF state
and the controller maintains the OFF state during the period in that the inductor current is larger than the
overcurrent trip level. In order to provide both good accuracy and cost effective solution, TPS53355 supports
temperature compensated MOSFET RDS(on) sensing. The TRIP pin should be connected to GND through the trip
voltage setting resistor, RTRIP. The TRIP terminal sources current (ITRIP) which is 10 μA typically at room
temperature, and the trip level is set to the OCL trip voltage VTRIP as shown in Equation 2.
VTRIP (mV ) = RTRIP (kW )´ ITRIP (mA )
(2)
The inductor current is monitored by the LL pin. The GND pin is used as the positive current sensing node and
the LL pin is used as the negative current sense node. The trip current, ITRIP has 4700ppm/°C temperature slope
to compensate the temperature dependency of the RDS(on).
As the comparison is made during the OFF state, VTRIP sets the valley level of the inductor current. Thus, the
load current at the overcurrent threshold, IOCP, can be calculated as shown in Equation 3.
IOCP =
VTRIP
(32 ´ RDS(on) )
IIND(ripple)
+
2
=
VTRIP
(32 ´ RDS(on) )
+
(VIN - VOUT )´ VOUT
1
´
2 ´ L ´ fSW
VIN
(3)
In an overcurrent or short circuit condition, the current to the load exceeds the current to the output capacitor
thus the output voltage tends to decrease. Eventually, it crosses the undervoltage protection threshold and shuts
down. After a hiccup delay (16 ms with 0.7 ms sort-start), the controller restarts. If the overcurrent condition
remains, the procedure is repeated and the device enters hiccup mode.
Overvoltage and Undervoltage Protection
TPS53355 monitors a resistor divided feedback voltage to detect over and under voltage. When the feedback
voltage becomes lower than 70% of the target voltage, the UVP comparator output goes high and an internal
UVP delay counter begins counting. After 1ms, TPS53355 latches OFF both high-side and low-side MOSFETs
drivers. The controller restarts after a hiccup delay (16 ms with 0.7 ms soft-start). This function is enabled 1.5-ms
after the soft-start is completed.
When the feedback voltage becomes higher than 120% of the target voltage, the OVP comparator output goes
high and the circuit latches OFF the high-side MOSFET driver and latches ON the low-side MOSFET driver. The
output voltage decreases. If the output voltage reaches UV threshold, then both high-side MOSFET and low-side
MOSFET driver will be OFF and the device restarts after a hiccup delay. If the OV condition remains, both
high-side MOSFET and low-side MOSFET driver remains OFF until the OV condition is removed.
UVLO Protection
The TPS53355 uses VREG undervoltage lockout protection (UVLO). When the VREG voltage is lower than 3.95
V, the device shuts off. When the VREG voltage is higher than 4.2 V, the device restarts. This is a non-latch
protection.
Thermal Shutdown
TPS53355 monitors the temperature of itself. If the temperature exceeds the threshold value (typically 145°C),
TPS53355 is shut off. When the temperature falls about 10°C below the threshold value, the device will turn back
on. This is a non-latch protection.
18
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Small Signal Model
From small-signal loop analysis, a buck converter using D-CAP™ mode can be simplified as shown in Figure 38.
TPS53355
Switching Modulator
VIN
VIN
R1
LL
VFB
PWM
1
+
R2
+
Control
Logic
and
Divider
L
VOUT
IIND
IC
IOUT
0.6 V
ESR
RLOAD
Voltage
Divider
VC
COUT
Output
Capacitor
UDG-11005
Figure 38. Simplified Modulator Model
The output voltage is compared with the internal reference voltage (ramp signal is ignored here for simplicity).
The PWM comparator determines the timing to turn on the high-side MOSFET. The gain and speed of the
comparator can be assumed high enough to keep the voltage at the beginning of each on cycle substantially
constant.
1
H (s ) =
s ´ ESR ´ COUT
(4)
For loop stability, the 0-dB frequency, ƒ0, defined below need to be lower than 1/4 of the switching frequency.
f
1
£ SW
f0 =
2p ´ ESR ´ COUT
4
(5)
According to the equation above, the loop stability of D-CAPTM mode modulator is mainly determined by the
capacitor's chemistry. For example, specialty polymer capacitors (SP-CAP) have an output capacitance in the
order of several 100 µF and ESR in range of 10 mΩ. These makes ƒ0 on the order of 100 kHz or less, creating a
stable loop. However, ceramic capacitors have an ƒ0 at more than 700 kHz, and need special care when used
with this modulator. An application circuit for ceramic capacitor is described in the External Component Selection
Using All Ceramic Output Capacitors section.
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External Component Selection
The external components selection is a simple process when using organic semiconductors or special polymer
output capacitors.
1. SELECT OPERATION MODE AND SOFT-START TIME
Select operation mode and soft-start time using Table 1.
2. SELECT SWITCHING FREQUENCY
Select the switching frequency from 250 kHz to 1 MHz using Table 2.
3. CHOOSE THE INDUCTOR
The inductance value should be determined to give the ripple current of approximately 1/4 to 1/2 of maximum
output current. Larger ripple current increases output ripple voltage and improves signal-to-noise ratio and
helps ensure stable operation, but increases inductor core loss. Using 1/3 ripple current to maximum output
current ratio, the inductance can be determined by Equation 6.
L=
IN(max ) - VOUT
1
IIND(ripple ) ´ fSW
´
(V
)´ V
VIN(max )
OUT
IN(max ) - VOUT
3
=
IOUT(max ) ´ fSW
´
(V
VIN(max)
)´ V
OUT
(6)
The inductor requires a low DCR to achieve good efficiency. It also requires enough room above peak
inductor current before saturation. The peak inductor current can be estimated in Equation 7.
IIND(peak ) =
VIN(max ) - VOUT ´ VOUT
VTRIP
1
+
´
32 ´ RDS(on ) L ´ fSW
VIN(max )
)
(
(7)
4. CHOOSE THE OUTPUT CAPACITOR(S)
When organic semiconductor capacitor(s) or specialty polymer capacitor(s) are used, for loop stability,
capacitance and ESR should satisfy Equation 5. For jitter performance, Equation 8 is a good starting point to
determine ESR.
´ 10mV ´ (1 - D) 10mV ´ L ´ fSW L ´ fSW
V
=
=
ESR = OUT
(W )
0.6 V ´ IIND(ripple )
0.6 V
60
where
•
•
D is the duty factor.
The required output ripple slope is approximately 10 mV per tSW (switching period) in terms of VFB terminal
voltage.
(8)
5. DETERMINE THE VALUE OF R1 AND R2
The output voltage is programmed by the voltage-divider resistor, R1 and R2 shown in Figure 38. R1 is
connected between VFB pin and the output, and R2 is connected between the VFB pin and GND.
Recommended R2 value is from 10 kΩ to 20 kΩ. Determine R1 using Equation 9.
IIND(ripple ) ´ ESR
- 0.6
VOUT 2
´ R2
R1 =
0.6
(9)
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6. CHOOSE THE OVERCURRENT SETTING RESISTOR
The overcurrent setting resistor, RTRIP, can be determined by Equation 10.
æ
æ
1
çç IOCP - ç
2
L
´
´ fSW
è
RTRIP (kW) = è
ö (VIN - VOUT )´ VOUT
÷´
VIN
ø
ITRIP (mA)
ö
÷÷ ´ 32 ´ RDS(on) (mW )
ø
where
•
•
ITRIP is the TRIP pin sourcing current (10 µA)
RDS(on) is the thermally compensated on-time resistance value of the low-side MOSFET
(10)
Use an RDS(on) value of 1.5 mΩ for an overcurrent level of approximately 30 A. Use an RDS(on) value of
1.7 mΩ for overcurrent level of approximately 10 A.
External Component Selection Using All Ceramic Output Capacitors
When a ceramic output capacitor is used, the stability criteria in Equation 5 cannot be satisfied. The ripple
injection approach as shown in Figure 2 is implemented to increase the ripple on the VFB pin and make the
system stable. In addition to the selections made using steps 1 through step 6 in the External Component
Selection section, the ripple injection components must be selected. The C2 value can be fixed at 1 nF. The
value of C1 can be selected between 10 nF to 200 nF.
L ´ COUT
t
> N ´ ON
R7 ´ C1
2
where
•
N is the coefficient to account for L and COUT variation
(11)
N is also used to provide enough margin for stability. It is recommended N=2 for VOUT ≤ 1.8 V and N=4 for VOUT
≥ 3.3 V or when L ≤ 250 nH. The higher VOUT needs a higher N value because the effective output capacitance is
reduced significantly with higher DC bias. For example, a 6.3-V, 22-µF ceramic capacitor may have only 8 µF of
effective capacitance when biased at 5 V.
Because the VFB pin voltage is regulated at the valley, the increased ripple on the VFB pin causes the increase
of the VFB DC value. The AC ripple coupled to the VFB pin has two components, one coupled from SW node
and the other coupled from the VOUT pin and they can be calculated using Equation 12 and Equation 13 when
neglecting the output voltage ripple caused by equivalent series inductance (ESL).
V - VOUT
D
´
VINJ _ SW = IN
R7 ´ C1
fSW
(12)
VINJ _ OUT = ESR ´ IIND(ripple ) +
IIND(ripple )
8 ´ COUT ´ fSW
(13)
It is recommended that VINJ_SW to be less than 50 mV. If the calculated VINJ_SW is higher than 50 mV, then other
parameters need to be adjusted to reduce it. For example, COUT can be increased to satisfy Equation 11 with a
higher R7 value, thereby reducing VINJ_SW.
The DC voltage at the VFB pin can be calculated by Equation 14:
VINJ _ SW + VINJ _ OUT
VVFB = 0.6 +
2
(14)
And the resistor divider value can be determined by Equation 15:
- VVFB
V
´ R2
R1 = OUT
VVFB
(15)
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LAYOUT CONSIDERATIONS
Certain points must be considered before starting a layout work using the TPS53355.
• The power components (including input/output capacitors, inductor and TPS53355) should be placed on one
side of the PCB (solder side). At least one inner plane should be inserted, connected to ground, in order to
shield and isolate the small signal traces from noisy power lines.
• All sensitive analog traces and components such as VFB, PGOOD, TRIP, MODE and RF should be placed
away from high-voltage switching nodes such as LL, VBST to avoid coupling. Use internal layer(s) as ground
plane(s) and shield feedback trace from power traces and components.
• Place the VIN decoupling capacitors as close to the VIN and PGND pins as possible to minimize the input AC
current loop.
• Because the TPS53355 controls output voltage referring to voltage across VOUT capacitor, the top-side
resistor of the voltage divider should be connected to the positive node of the VOUT capacitor. The GND of
the bottom side resistor should be connected to the GND pad of the device. The trace from these resistors to
the VFB pin should be short and thin.
• Place the frequency setting resistor (RF), OCP setting resistor (RTRIP) and mode setting resistor (RMODE) as
close to the device as possible. Use the common GND via to connect them to GND plane if applicable.
• Place the VDD and VREG decoupling capacitors as close to the device as possible. Ensure to provide GND
vias for each decoupling capacitor and make the loop as small as possible.
• The PCB trace defined as switch node, which connects the LL pins and high-voltage side of the inductor,
should be as short and wide as possible.
• Connect the ripple injection VOUT signal (VOUT side of the C1 capacitor in Figure 2) from the terminal of
ceramic output capacitor. The AC coupling capacitor (C2 in Figure 2) should be placed near the device, and
R7 and C1 can be placed near the power stage.
• Use separated vias or trace to connect LL node to snubber, boot strap capacitor and ripple injection
capacitor. Do not combine these connections.
GND shape
VOUT shape
VIN shape
LL shape
VDD
Bottom side
component
and trace
VREG
VBST
PGOOD
MODE
TRIP
RF
EN
VFB
GND
VOUT
Bottom side
components and trace
Keep VFB trace short and
away from noisy signals
Bottom side
components and trace
To GND Plane
UDG-11166
Figure 39. Layout Recommendation
22
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Copyright © 2011, Texas Instruments Incorporated
Product Folder Link(s): TPS53355
PACKAGE OPTION ADDENDUM
www.ti.com
18-Aug-2011
PACKAGING INFORMATION
Orderable Device
Status
(1)
Package Type Package
Drawing
Pins
Package Qty
Eco Plan
(2)
Lead/
Ball Finish
MSL Peak Temp
(3)
TPS53355DQPR
ACTIVE
SON
DQP
22
2500
Pb-Free (RoHS
Exempt)
CU NIPDAU Level-2-260C-1 YEAR
TPS53355DQPT
ACTIVE
SON
DQP
22
250
Pb-Free (RoHS
Exempt)
CU NIPDAU Level-2-260C-1 YEAR
Samples
(Requires Login)
(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
14-Jul-2012
TAPE AND REEL INFORMATION
*All dimensions are nominal
Device
Package Package Pins
Type Drawing
SPQ
Reel
Reel
A0
Diameter Width (mm)
(mm) W1 (mm)
B0
(mm)
K0
(mm)
P1
(mm)
W
Pin1
(mm) Quadrant
TPS53355DQPR
SON
DQP
22
2500
330.0
12.4
5.3
6.3
1.8
8.0
12.0
Q1
TPS53355DQPT
SON
DQP
22
250
180.0
12.4
5.3
6.3
1.8
8.0
12.0
Q1
Pack Materials-Page 1
PACKAGE MATERIALS INFORMATION
www.ti.com
14-Jul-2012
*All dimensions are nominal
Device
Package Type
Package Drawing
Pins
SPQ
Length (mm)
Width (mm)
Height (mm)
TPS53355DQPR
SON
DQP
22
2500
367.0
367.0
35.0
TPS53355DQPT
SON
DQP
22
250
210.0
185.0
35.0
Pack Materials-Page 2
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