TI TPS51216RUKR

TPS51216
www.ti.com
SLUSAB9 – NOVEMBER 2010
Complete DDR2, DDR3 and DDR3L Memory Power Solution Synchronous Buck
Controller, 2-A LDO, Buffered Reference
Check for Samples: TPS51216
FEATURES
DESCRIPTION
•
The TPS51216 provides a complete power supply for
DDR2, DDR3 and DDR3L memory systems in the
lowest total cost and minimum space. It integrates a
synchronous buck regulator controller (VDDQ) with a
2-A sink/source tracking LDO (VTT) and buffered low
noise reference (VTTREF). The TPS51216 employs
D-CAP™ mode coupled with 300 kHz/400 kHz
frequencies for ease-of-use and fast transient
response. The VTTREF tracks VDDQ/2 within
excellent 0.8% accuracy. The VTT, which provides 2A sink/source peak current capabilities, requires only
10-mF of ceramic capacitance. In addition, a
dedicated LDO supply input is available.
1
2
•
•
•
Synchronous Buck Controller (VDDQ)
– Conversion Voltage Range: 3 V to 28 V
– Output Voltage Range: 0.7 V to 1.8 V
– 0.8% VREF Accuracy
– D-CAP™ Mode for Fast Transient Response
– Selectable 300 kHz/400 kHz Switching
Frequencies
– Optimized Efficiency at Light and Heavy
Loads with Auto-skip Function
– Supports Soft-Off in S4/S5 States
– OCL/OVP/UVP/UVLO Protections
– Powergood Output
2-A LDO(VTT), Buffered Reference(VTTREF)
– 2-A (Peak) Sink and Source Current
– Requires Only 10-m
mF of Ceramic Output
Capacitance
– Buffered, Low Noise, 10-mA VTTREF
Output
– 0.8% VTTREF, 20-mV VTT Accuracy
– Support High-Z in S3 and Soft-Off in S4/S5
Thermal Shutdown
20-Pin, 3 mm × 3 mm, QFN Package
The TPS51216 provides rich useful functions as well
as excellent power supply performance. It supports
flexible power state control, placing VTT at high-Z in
S3 and discharging VDDQ, VTT and VTTREF (softoff) in S4/S5 state. Programmable OCL with low-side
MOSFET RDS(on) sensing, OVP/UVP/UVLO and
thermal shutdown protections are also available.
The TPS51216 is available in a 20-pin, 3 mm × 3
mm, QFN package and is specified for ambient
temperature from –40°C to 85°C.
VIN
5VIN
PGND
APPLICATIONS
•
•
DDR2/DDR3/DDR3L Memory Power Supplies
SSTL_18, SSTL_15, SSTL_135 and HSTL
Termination
PGND
TPS51216
VBST 15
12 V5IN
S3
17 S3
S5
16 S5
VDDQ
DRVH 14
SW 13
DRVL 11
6
VREF
PGND 10
PGOOD 20
8
7
REFIN
GND
19 MODE
18 TRIP
AGND
VDDQSNS
9
VLDOIN
2
VTT
3
VTTSNS
1
VTTGND
4
VTTREF
5
Powergood
VTT
VTTREF
AGND
PGND
UDG-10138
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.
D-CAP 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 © 2010, Texas Instruments Incorporated
TPS51216
SLUSAB9 – NOVEMBER 2010
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 (1)
ORDERABLE DEVICE
NUMBER
TA
PACKAGE
–40°C to 85°C
Plastic Quad Flat Pack (20 pin QFN)
(1)
TPS51216RUKR
TPS51216RUKT
PINS
20
OUTPUT
SUPPLY
MINIMUM
QUANTITY
Tape and reel
3000
Mini reel
250
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 (1)
over operating free-air temperature range (unless otherwise noted)
VALUE
MIN
MAX
VBST
–0.3
36
VBST (3)
–0.3
6
–5
30
VLDOIN, VDDQSNS, REFIN
–0.3
3.6
VTTSNS
–0.3
3.6
PGND, VTTGND
–0.3
0.3
V5IN, S3, S5, TRIP, MODE
–0.3
6
–5
36
DRVH (3)
–0.3
6
VTTREF, VREF
–0.3
3.6
VTT
–0.3
3.6
DRVL
–0.3
6
PGOOD
–0.3
6
SW
Input voltage range (2)
DRVH
Output voltage range (2)
Junction temperature range, TJ
Storage temperature range, TSTG
(1)
(2)
(3)
UNIT
–55
V
V
125
°C
150
°C
Stresses beyond those listed under absolute maximum ratings may cause permanent damage to the device. These are stress ratings
only and functional operation of the device at these or any other conditions beyond those indicated under recommended operating
conditions is not implied. Exposure to absolute-maximum-rated conditions for extended periods may affect device reliability.
All voltage values are with respect to the network ground terminal unless otherwise noted.
Voltage values are with respect to the SW terminal.
THERMAL INFORMATION
THERMAL METRIC
TPS51216
QFN (20) PINS
qJA
Junction-to-ambient thermal resistance
94.1
qJCtop
Junction-to-case (top) thermal resistance
58.1
qJB
Junction-to-board thermal resistance
64.3
yJT
Junction-to-top characterization parameter
31.8
yJB
Junction-to-board characterization parameter
58.0
qJCbot
Junction-to-case (bottom) thermal resistance
5.9
2
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UNITS
°C/W
Copyright © 2010, Texas Instruments Incorporated
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SLUSAB9 – NOVEMBER 2010
RECOMMENDED OPERATING CONDITIONS
MIN
Supply voltage
5.5
VBST
–0.1
33.5
VBST (1)
–0.1
5.5
-3
28
SW (2)
–4.5
28
VLDOIN, VDDQSNS, REFIN
–0.1
3.5
VTTSNS
–0.1
3.5
PGND, VTTGND
–0.1
0.1
S3, S5, TRIP, MODE
–0.1
5.5
–3
33.5
DRVH
Output voltage range
TA
(1)
(2)
MAX
4.5
SW
Input voltage range
TYP
V5IN
DRVH (1)
–0.1
5.5
DRVH (2)
–4.5
33.5
VTTREF, VREF
–0.1
3.5
VTT
–0.1
3.5
DRVL
–0.1
5.5
PGOOD
–0.1
5.5
Operating free-air temperature
–40
85
UNIT
V
V
V
°C
Voltage values are with respect to the SW terminal.
This voltage should be applied for less than 30% of the repetitive period.
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ELECTRICAL CHARACTERISTICS
over operating free-air temperature range, VV5IN=5V, VLDOIN is connected to VDDQ output, VMODE=0V, VS3=VS5=5V (unless
otherwise noted)
PARAMETER
TEST CONDITION
MIN
TYP
MAX
UNIT
SUPPLY CURRENT
IV5IN(S0)
V5IN supply current, in S0
TA = 25°C, No load, VS3 = VS5 = 5 V
590
IV5IN(S3)
V5IN supply current, in S3
TA = 25°C, No load, VS3 = 0 V, VS5 = 5 V
500
IV5INSDN
V5IN shutdown current
TA = 25°C, No load, VS3 = VS5 = 0 V
1
mA
IVLDOIN(S0)
VLDOIN supply current, in S0
TA = 25°C, No load, VS3 = VS5 = 5 V
5
mA
IVLDOIN(S3)
VLDOIN supply current, in S3
TA = 25°C, No load, VS3 = 0 V, VS5 = 5 V
5
mA
IVLDOINSDN
VLDOIN shutdown current
TA = 25°C, No load, VS3 = VS5 = 0 V
5
mA
V
mA
mA
VREF OUTPUT
IVREF = 30 mA, TA = 25°C
VVREF
Output voltage
IVREFOCL
Current limit
1.8000
0 mA ≤ IVREF <300 mA, TA = –10°C to 85°C
1.7856
1.8144
0 mA ≤ IVREF <300 mA, TA = –40°C to 85°C
1.7820
1.8180
VVREF = 1.7 V
0.4
0.8
mA
VTTREF OUTPUT
VVTTREF
Output voltage
VVDDQSNS/2
|IVTTREF| <100 mA, 1.2 V ≤ VVDDQSNS ≤ 1.8 V
49.2%
|IVTTREF| <10 mA, 1.2 V ≤ VVDDQSNS ≤ 1.8 V
49%
V
50.8%
VVTTREF
Output voltage tolerance to VVDDQ
IVTTREFOCLSRC
Source current limit
VVDDQSNS = 1.8 V, VVTTREF= 0 V
10
18
mA
IVTTREFOCLSNK
Sink current limit
VVDDQSNS = 1.8 V, VVTTREF = 1.8 V
10
17
mA
IVTTREFDIS
VTTREF discharge current
TA = 25°C, VS3 = VS5 = 0 V, VVTTREF = 0.5 V
0.8
1.3
mA
|IVTT| ≤ 10 mA, 1.2 V ≤ VVDDQSNS ≤ 1.8 V, IVTTREF = 0 A
–20
20
|IVTT| ≤ 1 A, 1.2 ≤ VVDDQSNS ≤ 1.8 V, IVTTREF = 0 A
–30
30
|IVTT| ≤ 2 A, 1.4 V ≤ VVDDQSNS ≤ 1.8 V, IVTTREF = 0 A
–40
40
|IVTT| ≤ 1.5 A, 1.2 V ≤ VVDDQSNS ≤ 1.4 V, IVTTREF = 0 A
–40
40
51%
VTT OUTPUT
VVTT
Output voltage
VVTTTOL
Output voltage tolerance to VTTREF
VVTTREF
V
IVTTOCLSRC
Source current limit
VVDDQSNS = 1.8 V, VVTT = VVTTSNS = 0.7 V,
IVTTREF = 0 A
IVTTOCLSNK
Sink current limit
VVDDQSNS = 1.8V, VVTT = VVTTSNS = 1.1 V, IVTTREF = 0 A
IVTTLK
Leakage current
TA = 25°C , VS3 = 0 V, VS5 = 5 V, VVTT = VVTTREF
IVTTSNSBIAS
VTTSNS input bias current
VS3 = 5 V, VS5 = 5 V, VVTTSNS = VVTTREF
–0.5
0.0
0.5
IVTTSNSLK
VTTSNS leakage current
VS3 = 0 V, VS5 = 5 V, VVTTSNS = VVTTREF
–1
0
1
IVTTDIS
VTT Discharge current
TA = 25°C, VS3 = VS5 = 0 V, VVDDQSNS = 1.8 V,
VVTT = 0.5 V, IVTTREF = 0 A
2
3
2
3
mV
A
5
7.8
mA
mA
VDDQ OUTPUT
VVDDQSNS
VDDQ sense voltage
VVDDQSNSTOL
VDDQSNS regulation voltage
tolerance to REFIN
VREFIN
TA = 25°C
IVDDQSNS
VDDQSNS input current
VVDDQSNS = 1.8 V
IREFIN
REFIN input current
VREFIN = 1.8 V
IVDDQDIS
VDDQ discharge current
VS3 = VS5 = 0 V, VVDDQSNS = 0.5 V, MODE pin pulled
down to GND through 47kΩ (Non-tracking)
12
mA
IVLDOINDIS
VLDOIN discharge current
VS3 = VS5 = 0 V, VVDDQSNS = 0.5 V, MODE pin pulled
down to GND through 100kΩ (Non-tracking)
1.2
A
–3
3
39
–0.1
0.0
mV
mA
0.1
mA
SWITCH MODE POWER SUPPLY (SMPS) FREQUENCY
VIN = 12 V, VVDDQSNS = 1.8 V, RMODE = 100 kΩ
300
VIN = 12 V, VVDDQSNS = 1.8 V, RMODE = 200 kΩ
400
fSW
VDDQ switching frequency
tON(min)
Minimum on time
DRVH rising to falling (1)
tOFF(min)
Minimum off time
DRVH falling to rising
(1)
4
kHz
60
200
320
450
ns
Ensured by design. Not production tested.
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SLUSAB9 – NOVEMBER 2010
ELECTRICAL CHARACTERISTICS (continued)
over operating free-air temperature range, VV5IN=5V, VLDOIN is connected to VDDQ output, VMODE=0V, VS3=VS5=5V (unless
otherwise noted)
PARAMETER
TEST CONDITION
MIN
TYP
MAX
Source, IDRVH = –50 mA
1.6
3.0
Sink, IDRVH = 50 mA
0.6
1.5
Source, IDRVL = –50 mA
0.9
2.0
Sink, IDRVL = 50 mA
0.5
1.2
DRVH-off to DRVL-on
10
DRVL-off to DRVH-on
20
UNIT
VDDQ MOSFET DRIVER
RDRVH
RDRVL
tDEAD
DRVH resistance
DRVL resistance
Dead time
Ω
ns
INTERNAL BOOT STRAP SW
VFBST
Forward Voltage
VV5IN-VBST, TA = 25°C, IF = 10 mA
IVBSTLK
VBST leakage current
TA = 25°C, VVBST = 33 V, VSW = 28 V
0.1
0.2
V
0.01
1.5
mA
mA
LOGIC THRESHOLD
IMODE
MODE source current
MODE 0
VTHMODE
MODE threshold voltage
VIL
S3/S5 low-level voltage
VIH
S3/S5 high-level voltage
VIHYST
S3/S5 hysteresis voltage
VILK
S3/S5 input leak current
14
15
16
580
600
620
MODE 1
829
854
879
MODE 2
1202
1232
1262
MODE 3
1760
1800
1840
mV
0.5
1.8
V
0.25
–1
0
1
mA
SOFT START
tSS
VDDQ soft-start time
Internal soft-start time, CVREF = 0.1 mF,
S5 rising to VVDDQSNS > 0.99 × VREFIN
1.1
ms
PGOOD COMPARATOR
VTHPG
VDDQ PGOOD threshold
IPG
PGOOD sink current
tPGDLY
PGOOD delay time
tPGSSDLY
PGOOD start-up delay
PGOOD in from higher
106%
108%
PGOOD in from lower
90%
92%
94%
PGOOD out to higher
114%
116%
118%
PGOOD out to lower
82%
84%
86%
3
5.9
0.8
1
VPGOOD = 0.5 V
Delay for PGOOD in
110%
mA
1.2
ms
Delay for PGOOD out, with 100 mV over drive
330
ns
CVREF = 0.1 mF, S5 rising to PGOOD rising
2.5
ms
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ELECTRICAL CHARACTERISTICS (continued)
over operating free-air temperature range, VV5IN=5V, VLDOIN is connected to VDDQ output, VMODE=0V, VS3=VS5=5V (unless
otherwise noted)
PARAMETER
TEST CONDITION
MIN
TYP
MAX
9
10
11
UNIT
PROTECTIONS
ITRIP
TRIP source current
TCITRIP
TRIP source current temperature
coefficient (2)
VTRIP
VTRIP voltage range
VOCL
Current limit threshold
VOCLN
Negative current limit threshold
VZC
TA = 25°C, VTRIP = 0.4 V
4700
0.2
ppm/°C
3
VTRIP = 3.0 V
360
375
390
VTRIP = 1.6 V
190
200
210
VTRIP = 0.2 V
20
25
30
VTRIP = 3.0 V
–390
–375
–360
VTRIP = 1.6 V
–210
–200
–190
VTRIP = 0.2 V
–30
–25
–20
Wake-up
4.2
4.4
4.5
Shutdown
3.7
3.9
4.1
118%
120%
122%
Zero cross detection offset
0
VUVLO
V5IN UVLO threshold voltage
VOVP
VDDQ OVP threshold voltage
OVP detect voltage
tOVPDLY
VDDQ OVP propagation delay
With 100 mV over drive
VUVP
VDDQ UVP threshold voltage
UVP detect voltage
tUVPDLY
VDDQ UVP delay
tUVPENDLY
VDDQ UVP enable delay
VOOB
OOB Threshold voltage
68%
V
mV
mV
mV
430
66%
mA
V
ns
70%
1
ms
1.2
ms
108%
THERMAL SHUTDOWN
TSDN
(2)
6
Thermal shutdown threshold
Shutdown temperature (2)
Hysteresis
(2)
140
10
°C
Ensured by design. Not production tested.
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SLUSAB9 – NOVEMBER 2010
DEVICE INFORMATION
PGOOD
MODE
TRIP
S3
S5
RUK PACKAGE (TOP VIEW)
20
19
18
17
16
VTTSNS
1
15
VBST
VLDOIN
2
14
DRVH
VTT
3
13
SW
VTTGND
4
12
V5IN
VTTREF
5
11
DRVL
8
GND
REFIN
9
10
PGND
7
VDDQSNS
6
VREF
TPS51216
PowerPAD™
PIN FUNCTIONS
PIN
I/O
DESCRIPTION
NAME
NO.
DRVH
14
O
High-side MOSFET gate driver output.
DRVL
11
O
Low-side MOSFET gate driver output.
GND
7
–
Signal ground.
MODE
19
I
Connect resistor to GND to configure switching frequency and discharge mode. (See Table 2)
PGND
10
–
Gate driver power ground. RDS(on) current sensing input(+).
PGOOD
20
O
Powergood signal open drain output. PGOOD goes high when VDDQ output voltage is within the target range.
REFIN
8
I
Reference input for VDDQ. Connect to the midpoint of a resistor divider from VREF to GND. Add a capacitor for
stable operation.
SW
13
S3
17
I
S3 signal input. (See Table 1)
S5
16
I
S5 signal input. (See Table 1)
TRIP
18
I
Connect resistor to GND to set OCL at VTRIP/8. Output 10-mA current at room temperature, TC = 4700 ppm/°C.
VBST
15
I
High-side MOSFET gate driver bootstrap voltage input. Connect a capacitor from the VBST pin to the SW pin.
VDDQSNS
9
I
VDDQ output voltage feedback. Reference input for VTTREF. Also serves as power supply for VTTREF.
VLDOIN
2
I
Power supply input for VTT LDO. Connect VDDQ in typical application.
VREF
6
O
1.8-V reference output.
VTT
3
O
VTT 2-A LDO output. Need to connect 10mF or larger capacitance for stability.
VTTGND
4
–
Power ground for VTT LDO.
VTTREF
5
O
Buffered VTT reference output. Need to connect 0.22mF or larger capacitance for stability.
VTTSNS
1
I
VTT output voltage feedback.
V5IN
12
I
5-V power supply input for internal circuits and MOSFET gate drivers.
Thermal
pad
–
–
Connect to GND
I/O High-side MOSFET gate driver return. RDS(on) current sensing input(–).
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FUNCTIONAL BLOCK DIAGRAM
VREFIN –32%
+
UV
+
OV
VREFIN +8/16 %
20 PGOOD
+
Delay
+
VREFIN +20%
VREFIN –8/16 %
15 mA
REFIN
VREF
8
UVP
6
Reference
+
+
PWM
19 MODE
15 VBST
9
14 DRVH
10 mA
13 SW
8R
+
TRIP 18
OC
XCON
+
S5 16
7R
tON
OneShot
R
S3 17
GND
On-Time
Discharge Type
Selection
OVP
Soft-Start
VDDQSNS
Control Logic
NOC
+
7
12 V5IN
R
11 DRVL
+
ZC
VTT Discharge
VDDQ
Discharge V5OK VTTREF Discharge
VTTREF
5
10
PGND
2
VLDOIN
3
VTT
4
VTTGND
+
+
+
VTTSNS
+
4.4 V/3.9 V
1
+
TPS51216
UDG-10135
8
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TYPICAL CHARACTERISTICS
10
V5IN Shutdown Current (µA)
V5IN Suppy Current (µA)
1000
800
600
400
200
0
−50
−25
0
25
50
75
Junction Temperature (°C)
100
4
2
−25
0
25
50
75
Junction Temperature (°C)
100
125
Figure 2. V5IN Shutdown Current vs Junction Temperature
10
16
14
8
TRIP Source Current (µA)
VLDOIN Suppy Current (µA)
6
0
−50
125
Figure 1. V5IN Supply Current vs Junction Temperature
6
4
2
12
10
8
6
0
−50
−25
0
25
50
75
Junction Temperature (°C)
100
4
−50
125
Figure 3. VLDOIN Supply Current vs Junction
Temperature
0
25
50
75
Junction Temperature (°C)
100
125
130
120
110
100
90
80
70
60
−25
0
25
50
75
Junction Temperature (°C)
100
125
Figure 5. OVP/UVP Threshold vs Junction Temperature
VDDQSNS Discharge Current (mA)
15
OVP
UVP
140
50
−50
−25
Figure 4. Current Sense Current vs Junction Temperature
150
OVP/UVP Threshold (%)
8
12
9
6
3
0
−50
−25
0
25
50
75
Junction Temperature (°C)
100
125
Figure 6. VDDQSNS Discharge Current vs Junction
Temperature
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TYPICAL CHARACTERISTICS (continued)
800
8
Switching Frequency (kHz)
VTT Discharge Current (mA)
10
6
4
2
700
600
500
400
300
0
−50
−25
0
25
50
75
Junction Temperature (°C)
100
200
125
Figure 7. VTT Discharge Current vs Junction Temperature
500
400
Switching Frequency (kHz)
Switching Frequency (kHz)
600
12
14
16
Input Voltage (V)
18
20
22
VVDDQ = 1.20 V
VVDDQ = 1.35 V
VVDDQ = 1.50 V
600
500
400
300
200
100
6
8
10
12
14
16
Input Voltage (V)
18
20
0
22
Figure 9. Switching Frequency vs Input Voltage
0
2
4
6
8
10
12
14
VDDQ Output Current (A)
16
18
20
Figure 10. Switching Frequency vs Load Current
800
1.55
VVDDQ = 1.20 V
VVDDQ = 1.35 V
VVDDQ = 1.50 V
600
500
400
300
200
100
RMODE = 200 kΩ
VIN = 12 V
1.54
VDDQ Output Voltage (V)
RMODE = 200 kΩ
VIN = 12 V
700
1.53
1.52
1.51
1.50
1.49
1.48
1.47
1.46
0
2
4
6
8
10
12
14
VDDQ Output Current (A)
16
18
20
1.45
0
Figure 11. Switching Frequency vs Load Current
10
10
RMODE = 100 kΩ
VIN = 12 V
700
300
Switching Frequency (kHz)
8
800
VVDDQ = 1.20 V
VVDDQ = 1.35 V
VVDDQ = 1.50 V
RMODE = 200 kΩ
IVDDQ = 10 A
700
0
6
Figure 8. Switching Frequency vs Input Voltage
800
200
VVDDQ = 1.20 V
VVDDQ = 1.35 V
VVDDQ = 1.50 V
RMODE = 100 kΩ
IVDDQ = 10 A
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2
4
6
8
10
12
14
VDDQ Output Current (A)
16
18
20
Figure 12. Load Regulation
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TYPICAL CHARACTERISTICS (continued)
1.55
0.770
0.765
1.53
VTTREF Voltage (V)
VDDQ Output Voltage (V)
IVDDQ = 0 A
IVDDQ = 20 A
RMODE = 200 kΩ
1.54
1.52
1.51
1.50
1.49
1.48
0.760
0.755
0.750
0.745
0.740
1.47
0.735
1.46
1.45
VVDDQ = 1.5 V
6
8
10
12
14
16
Input Voltage (V)
18
20
0.730
−10
22
−5
Figure 13. Line Regulation
0.620
0.690
0.615
VTTREF Voltage (V)
VTTREF Voltage (V)
0.685
0.680
0.675
0.670
0.665
0.660
10
0.610
0.605
0.600
0.595
0.590
0.585
VVDDQ = 1.35 V
0.650
−10
−5
VVDDQ = 1.2 V
0
VTTREF Current (mA)
5
0.580
−10
10
Figure 15. VTTREF Load Regulation
−5
0
VTTREF Current (mA)
5
10
Figure 16. VTTREF Load Regulation
0.790
0.715
0.780
0.705
0.770
0.695
VTT Voltage (V)
VTT Voltage (V)
5
Figure 14. VTTREF Load Regulation
0.695
0.655
0
VTTREF Current (mA)
0.760
0.750
0.740
0.730
0.685
0.675
0.665
0.655
0.720
0.645
VVDDQ = 1.5 V
0.710
−2.0
−1.5
−1.0
−0.5
0.0
0.5
VTT Current (V)
1.0
1.5
2.0
VVDDQ = 1.35 V
0.635
−2.0 −1.5 −1.0
Figure 17. VTT Load Regulation
−0.5
0.0
0.5
VTT Current (V)
1.0
1.5
Figure 18. VTT Load Regulation
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TYPICAL CHARACTERISTICS (continued)
0.640
100
0.630
90
80
70
Efficiency (%)
VTT Voltage (V)
0.620
0.610
0.600
0.590
60
50
40
30
0.580
20
0.570
VVDDQ = 1.2 V
0.560
−2.0 −1.5 −1.0
12
10
−0.5
0.0
0.5
VTT Current (V)
1.0
1.5
2.0
VVDDQ = 1.5 V
RMODE = 200 kΩ
0
0.001
0.01
0.1
1
VDDQ Output Current (A)
VIN = 20 V
VIN = 12 V
VIN = 8 V
10
Figure 19. VTT Load Regulation
Figure 20. Efficiency
Figure 21. 1.5-V Load Transient Response
Figure 22. VTT Load Transient Response
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TYPICAL CHARACTERISTICS (continued)
Figure 23. 1.5-V Startup Waveforms
Figure 24. 1.5-V Startup Waveforms (0.5-V Pre-Biased)
Figure 25. 1.5-V Soft-Stop Waveforms (Tracking
Discharge)
Figure 26. 1.5-V Soft-Stop Waveforms (Non-Tracking
Discharge)
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180
60
135
60
135
40
90
40
90
20
45
20
45
0
0
0
0
−20
−45
−40
−60
Gain
Phase
IVTT = −1 A
−80
10000
−20
−45
−90
−40
−90
−135
−60
−180
10000000
100000
1000000
Frequency (Hz)
−80
10000
Figure 27. VTT Bode Plot (Sink)
14
Gain
Phase
IVTT = 1 A
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100000
1000000
Frequency (Hz)
Phase (°)
80
Gain (dB)
180
Phase (°)
Gain (dB)
TYPICAL CHARACTERISTICS (continued)
80
−135
−180
10000000
Figure 28. VTT Bode Plot (Source)
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APPLICATION INFORMATION
VDDQ Switch Mode Power Supply Control
TPS51216 supports D-CAP™ mode which does not require complex external compensation networks and is
suitable for designs with small external components counts. The D-CAP™ mode provides fast transient response
with appropriate amount of equivalent series resistance (ESR) on the output capacitors. An adaptive on-time
control scheme is used to achieve pseudo-constant frequency. The TPS51216 adjusts the on-time (tON) to be
inversely proportional to the input voltage (VIN) and proportional to the output voltage (VDDQ). This makes a
switching frequency fairy constant over the variation of input voltage at the steady state condition.
VREF and REFIN, VDDQ Output Voltage
The part provides a 1.8-V, ±0.8% accurate, voltage reference from VREF. This output has a 300-mA (max)
current capability to drive the REFIN input voltage through a voltage divider circuit. A capacitor with a value of
0.1-mF or larger should be attached close to the VREF terminal.
The VDDQ switch-mode power supply (SMPS) output voltage is defined by REFIN voltage, within the range
between 0.7 V and 1.8 V, programmed by the resister-divider connected between VREF and GND. (See External
Components Selection section.) A few nano farads of capacitance from REFIN to GND is recommended for
stable operation.
Soft-Start and Powergood
TPS51216 provides integrated VDDQ soft-start functions to suppress in-rush current at start-up. The soft-start is
achieved by controlling internal reference voltage ramping up. Figure 29 shows the start-up waveforms. The
switching regulator waits for 400ms after S5 assertion. The MODE pin voltage is read in this period. A typical
VDDQ ramp up duration is 700ms.
TPS51216 has a powergood open-drain output that indicates the VDDQ voltage is within the target range. The
target voltage window and transition delay times of the PGOOD comparator are ±8% (typ) and 1-ms delay for
assertion (low to high), and ±16% (typ) and 330-ns delay for de-assertion (high to low) during running. The
PGOOD comparator is enabled 1.1 ms after VREF is raised high and the start-up delay is 2.5 ms. Note that the
time constant which is composed of the REFIN capacitor and a resistor divider needs to be short enough to
reach the target value before PGOOD comparator enabled.
S5
VREF
VDDQ
PGOOD
400 ms
700 ms
1.4 ms
UDG-10137
Figure 29. Typical Start-up Waveforms
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Power State Control
The TPS51216 has two input pins, S3 and S5, to provide simple control scheme of power state. All of VDDQ,
VTTREF and VTT are turned on at S0 state (S3=S5=high). In S3 state (S3=low, S5=high), VDDQ and VTTREF
voltages are kept on while VTT is turned off and left at high impedance state (high-Z). The VTT output floats and
does not sink or source current in this state. In S4/S5 states (S3=S5=low), all of the three outputs are turned off
and discharged to GND according to the discharge mode selected by MODE pin. Each state code represents as
follow; S0 = full ON, S3 = suspend to RAM (STR), S4 = suspend to disk (STD), S5 = soft OFF. (See Table 1)
Table 1. S3/S5 Power State Control
STATE
S3
S5
VREF
VDDQ
VTTREF
S0
HI
HI
ON
ON
ON
VTT
ON
S3
LO
HI
ON
ON
ON
OFF(High-Z)
S4/S5
LO
LO
OFF
OFF(Discharge)
OFF(Discharge)
OFF(Discharge)
MODE Pin Configuration
The TPS51216 reads the MODE pin voltage when the S5 signal is raised high and stores the status in a register.
A 15-mA current is sourced from the MODE pin during this time to read the voltage across the resistor connected
between the pin and GND. Table 2 shows resistor values, corresponding switching frequency and discharge
mode configurations.
Table 2. MODE Selection
MODE NO.
RESISTANCE BETWEEN
MODE AND GND ( kΩ)
SWITCHING
FREQUENCY (kHz)
DISCHARGE MODE
3
200
400
Tracking
2
100
300
1
68
300
0
47
400
Non-tracking
Discharge Control
In S4/S5 state, VDDQ, VTT, and VTTREF outputs are discharged based on the respective discharge mode
selected above. The tracking discharge mode discharges VDDQ output through the internal VTT regulator
transistors enabling quick discharge operation. The VTT output maintains tracking of the VTTREF voltage in this
mode. (Please refer to Figure 25) After 4 ms of tracking discharge operation, the mode changes to non-tracking
discharge. The VDDQ output must be connected to the VLDOIN pin in this mode. The non-tracking mode
discharges the VDDQ and VTT pins using internal MOSFETs that are connected to corresponding output
terminals. The non-tracking discharge is slow compared with the tracking discharge due to the lower current
capability of these MOSFETs. (Please refer to Figure 26)
16
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D-CAP™ Mode
Figure 30 shows a simplified model of D-CAP™ mode architecture.
VIN
VDDQSNS
DRVH
9
14
Lx
PWM
+
REFIN
Control
Logic
and
Driver
8
R1 VREF
R2
DRVL
1.8 V
VDDQ
ESR
6
+
High-Side
MOSFET
11
Low-Side
MOSFET
RLOAD
COUT
UDG-10136
Figure 30. Simplified D-CAP™ Model
The VDDQSNS voltage is compared with REFIN voltage. The PWM comparator creates a set signal to turn on
the high-side MOSFET. The gain and speed of the comparator is high enough to maintain the voltage at the
beginning of each on-cycle (or the end of each off-cycle) to be substantially constant. The DC output voltage
monitored at VDDQ may have line regulation due to ripple amplitude that slightly increases as the input voltage
increase. The D-CAP™ mode offers flexibility on output inductance and capacitance selections and provides
ease-of-use with a low external component count. However, it requires a sufficient amount of output ripple
voltage for stable operation and good jitter performance.
The requirement for loop stability is simple and is described in Equation 1. The 0-dB frequency, f0 defined in
Equation 1, is recommended to be lower than 1/3 of the switching frequency to secure proper phase margin.
f
1
£ SW
f0 =
2p ´ ESR ´ COUT
3
where
•
•
•
ESR is the effective series resistance of the output capacitor
COUT is the capacitance of the output capacitor
fsw is switching frequency
(1)
Jitter is another attribute caused by signal-to-noise ratio of the feedback signal. One of the major factors that
determine jitter performance in D-CAP™ mode is the down-slope angle of the VDDQSNS ripple voltage.
Figure 31 shows, in the same noise condition, a jitter is improved by making the slope angle larger.
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VVDDQSNS
Slope (1)
Jitter
(2)
Slope (2)
Jitter
20 mV
(1)
VREFIN
VREFIN +Noise
tON
tOFF
UDG-10139
Figure 31. Ripple Voltage Slope and Jitter Performance
For a good jitter performance, use the recommended down slope of approximately 20 mV per switching period as
shown in Figure 31 and Equation 2.
VOUT ´ ESR
³ 20mV
fSW ´ L X
where
•
•
VOUT is the VDDQ output voltage
LX is the inductance
(2)
Light-Load Operation
In auto-skip mode, the TPS51216 SMPS control logic automatically reduces its switching frequency to improve
light-load efficiency. To achieve this intelligence, a zero cross detection comparator is used to prevent negative
inductor current by turning off the low-side MOSFET. Equation 3 shows the boundary load condition of this skip
mode and continuous conduction operation.
ILOAD(LL) =
(VIN - VOUT ) ´ VOUT ´
2 ´ LX
VIN
1
fSW
(3)
VTT and VTTREF
TPS51216 integrates two high performance, low-drop-out linear regulators, VTT and VTTREF, to provide
complete DDR2/DDR3/DDR3L power solutions. The VTTREF has a 10-mA sink/source current capability, and
tracks ½ of VDDQSNS with ±1% accuracy using an on-chip ½ divider. A 0.22-mF (or larger) ceramic capacitor
must be connected close to the VTTREF terminal for stable operation. The VTT responds quickly to track
VTTREF within ±40 mV at all conditions, and the current capability is 2 A for both sink and source. A 10-mF (or
larger) ceramic capacitor(s) need to be connected close to the VTT terminal for stable operation. To achieve tight
regulation with minimum effect of wiring resistance, a remote sensing terminal, VTTSNS, should be connected to
the positive node of VTT output capacitor(s) as a separate trace from the high-current line to the VTT pin.
(Please refer to the Layout Considerations section for details.)
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VDDQ Overvoltage and Undervoltage Protection
TPS51216 sets the overvoltage protection (OVP) when the VDDQSNS voltage reaches a level 20% (typ) higher
than the REFIN voltage. When an OV event is detected, the controller latches DRVH low and DRVL high.
VTTREF and VTT are turned off and discharged using the non-tracking discharge MOSFETs regardless of the
tracking mode.
The undervoltage protection (UVP) latch is set when the VDDQSNS voltage remains lower than 68% (typ) of the
REFIN voltage for 1 ms or longer. In this fault condition, the controller latches DRVH low and DRVL low and
discharges the VDDQ, VTT and VTTREF outputs. UVP detection function is enabled after 1.2 ms of SMPS
operation to ensure startup.
To release the OVP and UVP latches, toggle S5 or adjust the V5IN voltage down and up beyond the
undervoltage lockout threshold.
VDDQ Overcurrent Protection
The VDDQ SMPS has cycle-by-cycle overcurrent limiting protection. The inductor current is monitored during the
off-state using the low-side MOSFET RDS(on) and the controller maintains the off-state while the voltage across
the low-side MOSFET is larger than the overcurrent trip level. The current monitor circuit inputs are PGND and
SW pins so that those should be properly connected to the source and drain terminals of low-side MOSFET. The
overcurrent trip level, VTRIP, is determined by Equation 4, where RTRIP is the value of the resistor connected
between the TRIP pin and GND, and ITRIP is the current sourced from the TRIP pin. ITRIP is 10 mA typically at
room temperature, and has 4700ppm/°C temperature coefficient to compensate the temperature dependency of
the low-side MOSFET RDS(on).
VTRIP = RTRIP ´ ITRIP
(4)
Because the comparison is done during the off-state, VTRIP sets the valley level of the inductor current. The load
current OCL level, IOCL, can be calculated by considering the inductor ripple current as shown in Equation 5
æ V
ö IIND(ripple ) æ V
ö 1 V -V
VOUT
OUT
TRIP
TRIP
÷+
÷ + ´ IN
=ç
´
IOCL = ç
ç 8 ´ RDS(on ) ÷
ç 8 ´ RDS(on ) ÷ 2
2
LX
fSW ´ VIN
è
ø
è
ø
where
•
IIND(ripple) is inductor ripple current
(5)
In an overcurrent condition, the current to the load exceeds the current to the output capacitor, thus the output
voltage tends to fall down. Eventually, it crosses the undervoltage protection threshold and shuts down.
VTT Overcurrent Protection
The LDO has an internally fixed constant overcurrent limiting of 3-A (typ) for both sink and source operation.
V5IN Undervoltage Lockout Protection
TPS51216 has a 5-V supply undervoltage lockout protection (UVLO) threshold. When the V5IN voltage is lower
than UVLO threshold voltage, typically 3.93 V, VDDQ, VTT and VTTREF are shut off. This is a non-latch
protection.
Thermal Shutdown
TPS51216 includes an internal temperature monitor. If the temperature exceeds the threshold value, 140°C (typ),
VDDQ, VTT and VTTREF are shut off. The thermal shutdown state of VDDQ is open, VTT and VTTREF are high
impedance (high-Z) respectively, and the discharge functions are disabled. This is a non-latch protection and the
operation is restarted with soft-start sequence when the device temperature is reduced by 10°C (typ).
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External Components Selection
The external components selection is simple in D-CAP™ mode.
1. DETERMINE THE VALUE OF R1 AND R2
The output voltage is determined by the value of the voltage-divider resistor, R1 and R2 as shown in
Figure 30. R1 is connected between VREF and REFIN pins, and R2 is connected between the REFIN pin
and GND. Setting R1 as 10-kΩ is a good starting point. Determine R2 using Equation 6.
R1
R2 =
æ
ö
ç
÷
ç
÷
1.8
ç
÷ -1
æ IIND(ripple ) ´ ESR ö ÷
ç
÷÷
ç VOUT - ç
ç
÷÷
2
ç
è
øø
è
(6)
2. CHOOSE THE INDUCTOR
The inductance value should be determined to yield a ripple current of approximately ¼ to ½ of maximum
output current. Larger ripple current increases output ripple voltage and improves the signal-to-noise ratio
and helps stable operation.
LX =
1
IIND(ripple ) ´ fSW
IN(max ) - VOUT
´
(V
VIN(max )
)´ V
OUT
=
3
IO(max ) ´ fSW
IN(max ) - VOUT
´
(V
VIN(max )
)´ V
OUT
(7)
The inductor needs a low direct current resistance (DCR) to achieve good efficiency, as well as enough room
above peak inductor current before saturation. The peak inductor current can be estimated in Equation 8.
IIND(peak ) =
VIN(max ) - VOUT ´ VOUT
VTRIP
1
+
´
8 ´ RDS(on ) L X ´ fSW
VIN(max )
(
)
(8)
3. CHOOSE THE OCL SETTING RESISTANCE, RTRIP
Combining Equation 4 and Equation 5, RTRIP can be obtained using Equation 9.
RTRIP
æ
ö
æ (V - VOUT ) ö
VOUT
÷ ´ RDS(on)
´
8 ´ ç IOCL - ç IN
÷
ç (2 ´ L X ) ÷ (fSW ´ VIN ) ÷
ç
è
ø
è
ø
=
ITRIP
(9)
4. CHOOSE THE OUTPUT CAPACITORS
Organic semiconductor capacitor(s) or specialty polymer capacitor(s) are recommended. Determine ESR to
meet small signal stability and recommended ripple voltage. A quick reference is shown in Equation 10 and
Equation 11.
f
1
£ SW
2p ´ ESR ´ COUT
3
(10)
VOUT ´ ESR
³ 20mV
fSW ´ L X
20
(11)
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TPS51216 Application Circuit
V5IN
4.5 V to 5.5 V
R2 200 kW
R1
100 kW
R3 36 kW
S5
S3
17
16
MODE
TRIP
S3
S5
1
VTTSNS
2
VLDOIN
3
VTT
4
VTTGND
5
VTTREF
DRVH 14
U1
TPS51216RUK
R6
0W
C7
0.1 mF
C5
0.1 mF
C8
10 mF
C9
10 mF
C10
10 mF
PGND
Q1
FDMS8680
R7 0 W
L1
0.56 mH
VDDQ
1.5 V/20 A
SW 13
VDDQSNS
PGND
V5IN 12
6
7
8
9
10
VTTREF
0.75 V
VIN
8 V to 20 V
VBST 15
REFIN
PGND
18
GND
VTTGND
19
VREF
C1
10 mF
20
PGOOD
PGND
VTT
0.75 V/2 A
21
PwPad
AGND
C12
10 mF
Q2
FDMS8670AS
DRVL 11
Q3
FDMS8670AS
C6
1 mF
C11
330 mF
VDDQ_GND
R4
10 kW
C2
C3
0.22 mF 0.1 mF
C4
10 nF
R5
49 kW
PGND
AGND
UDG-10165
Figure 32. DDR3, 400-kHz Application Circuit, Tracking Discharge
Table 3. DDR3, 400-kHz Application Circuit, List of Materials
REFERENCE
DESIGNATOR
QTY
SPECIFICATION
MANUFACTURE
PART NUMBER
Taiyo Yuden
TMK325BJ106MM
C8, C9, C10
3
10 µF, 25 V
C11
1
330 µF, 2V, 6 mΩ
Panasonic
EEFSX0D331XE
L1
1
0.56 µH, 21 A, 1.56 mΩ
Panasonic
ETQP4LR56WFC
Q1
1
30 V, 35 A, 8.5 mΩ
Fairchild
FDMS8680
Q2, Q3
2
30 V, 42 A, 3.5 mΩ
Fairchild
FDMS8670AS
For this example, the bulk output capacitor ESR requirement for D-CAP™ mode is described in Equation 12,
whichever is greater.
20mV ´ fSW ´ L
3
ESR ³
or ESR ³
VOUT
2p ´ fSW ´ COUT
(12)
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Layout Considerations
Certain issues must be considered before designing a layout using the TPS51216.
2
VLDOIN
VTT
VTT
TPS51216
VIN
3
10 mF
VTTGND
VTTGND
4
V5IN
VTTREF
VOUT
1 mF
#2
5
DRVL
MODE
0.22 mF
#1
12
11
19
#3
PGND
TRIP
18
10
VREF
6
REFIN
8
GND
7
0.1 mF
10 nF
UDG-10166
Figure 33. DC/DC Converter Ground System
•
•
•
•
22
VIN capacitor(s), VOUT capacitor(s) and MOSFETs are the power components and should be placed on one
side of the PCB (solder side). Other small signal components should be placed on another side (component
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 VDDQSNS, VTTSNS, MODE, REFIN, VREF and TRIP
should be placed away from high-voltage switching nodes such as SW, DRVL, DRVH or VBST to avoid
coupling. Use internal layer(s) as ground plane(s) and shield feedback trace from power traces and
components.
The DC/DC converter has several high-current loops. The area of these loops should be minimized in order to
suppress generating switching noise.
– The most important loop to minimize the area of is the path from the VIN capacitor(s) through the high and
low-side MOSFETs, and back to the capacitor(s) through ground. Connect the negative node of the VIN
capacitor(s) and the source of the low-side MOSFET at ground as close as possible. (Refer to loop #1 of
Figure 33)
– The second important loop is the path from the low-side MOSFET through inductor and VOUT
capacitor(s), and back to source of the low-side MOSFET through ground. Connect source of the low-side
MOSFET and negative node of VOUT capacitor(s) at ground as close as possible. (Refer to loop #2 of
Figure 33)
– The third important loop is of gate driving system for the low-side MOSFET. To turn on the low-side
MOSFET, high current flows from V5IN capacitor through gate driver and the low-side MOSFET, and back
to negative node of the capacitor through ground. To turn off the low-side MOSFET, high current flows
from gate of the low-side MOSFET through the gate driver and PGND, and back to source of the low-side
MOSFET through ground. Connect negative node of V5IN capacitor, source of the low-side MOSFET and
PGND at ground as close as possible. (Refer to loop #3 of Figure 33)
Because the TPS51216 controls output voltage referring to voltage across VOUT capacitor, VDDQSNS
should be connected to the positive node of VOUT capacitor. In a same manner GND should be connected to
the negative node of VOUT capacitor.
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•
•
•
•
•
•
•
•
•
•
•
•
SLUSAB9 – NOVEMBER 2010
Connect the overcurrent setting resistors from TRIP pin to ground and make the connections as close as
possible to the device. The trace from TRIP pin to resistor and from resistor to ground should avoid coupling
to a high-voltage switching node.
Connect the frequency and mode setting resistor from MODE pin to ground, and make the connections as
close as possible to the device. The trace from the MODE pin to the resistor and from the resistor to ground
should avoid coupling to a high-voltage switching node
Connections from gate drivers to the respective gate of the high-side or the low-side MOSFET should be as
short as possible to reduce stray inductance. Use 0.65 mm (25 mils) or wider trace and via(s) of at least 0.5
mm (20 mils) diameter along this trace.
The PCB trace defined as SW node, which connects to the source of the switching MOSFET, the drain of the
rectifying MOSFET and the high-voltage side of the inductor, should be as short and wide as possible.
VLDOIN should be connected to VDDQ output with short and wide traces. An input bypass capacitor should
be placed as close as possible to the pin with short and wide connections.
The output capacitor for VTT should be placed close to the pin with a short and wide connection in order
to avoid additional ESR and/or ESL of the trace.
VTTSNS should be connected to the positive node of the VTT output capacitor(s) as a separate trace from
the high-current power line and is strongly recommended to avoid additional ESR and/or ESL. If it is needed
to sense the voltage at the point of the load, it is recommended to attach the output capacitor(s) at that
point. Also, it is recommended to minimize any additional ESR and/or ESL of ground trace between GND pin
and the output capacitor(s).
Consider adding a low pass filter (LPF) at VTTSNS in case the ESR of the VTT output capacitor(s) is larger
than 2 mΩ.
VDDQSNS can be connected separately from VLDOIN. Remember that this sensing potential is the
reference voltage of VTTREF. Avoid any noise generative lines.
The negative node of the VTT output capacitor(s) and the VTTREF capacitor should be tied together by
avoiding common impedance to high-current path of the VTT source/sink current.
GND pin node represents the reference potential for VTTREF and VTT outputs. Connect GND to negative
nodes of VTT capacitor(s), VTTREF capacitor and VDDQ capacitor(s) with care to avoid additional ESR
and/or ESL. GND and PGND should be connected together at a single point.
In order to effectively remove heat from the package, prepare the thermal land and solder to the
package thermal pad. Wide trace of the component-side copper, connected to this thermal land, helps heat
spreading. Numerous vias with a 0.3-mm diameter connected from the thermal land to the internal/solderside ground plane(s) should be used to help dissipation.
CAUTION
Do NOT connect PGND pin directly to this thermal land underneath the package.
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Copyright © 2010, Texas Instruments Incorporated
Product Folder Link(s) :TPS51216
23
PACKAGE OPTION ADDENDUM
www.ti.com
10-Dec-2010
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)
TPS51216RUKR
ACTIVE
QFN
RUK
20
3000
Green (RoHS
& no Sb/Br)
CU NIPDAU Level-2-260C-1 YEAR
Purchase Samples
TPS51216RUKT
ACTIVE
QFN
RUK
20
250
Green (RoHS
& no Sb/Br)
CU NIPDAU Level-2-260C-1 YEAR
Request Free Samples
(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
8-Dec-2010
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
TPS51216RUKR
QFN
RUK
20
3000
330.0
12.4
3.3
3.3
1.1
8.0
12.0
Q2
TPS51216RUKT
QFN
RUK
20
250
180.0
12.4
3.3
3.3
1.1
8.0
12.0
Q2
Pack Materials-Page 1
PACKAGE MATERIALS INFORMATION
www.ti.com
8-Dec-2010
*All dimensions are nominal
Device
Package Type
Package Drawing
Pins
SPQ
Length (mm)
Width (mm)
Height (mm)
TPS51216RUKR
QFN
RUK
20
3000
346.0
346.0
29.0
TPS51216RUKT
QFN
RUK
20
250
190.5
212.7
31.8
Pack Materials-Page 2
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