Texas Instruments TPS51220EVM User manual

User’s Guide
TPS51220 Buck Controller Evaluation Module User's
Guide
Table of Contents
1 Description.............................................................................................................................................................................. 2
2 Electrical Performance...........................................................................................................................................................2
3 Schematic................................................................................................................................................................................3
4 Test Setup and Procedure......................................................................................................................................................4
4.1 Test Setup.......................................................................................................................................................................... 4
4.2 Test Procedure................................................................................................................................................................... 4
5 Configuration.......................................................................................................................................................................... 5
5.1 Switching Frequency Selection.......................................................................................................................................... 5
5.2 Skip Mode and Control Scheme Selection.........................................................................................................................5
5.3 Current-Sensing Selection................................................................................................................................................. 5
5.4 Overcurrent Limit and Discharge Selection........................................................................................................................6
5.5 Control Mode and Protection Selection..............................................................................................................................6
5.6 Soft-Start Setting Selection................................................................................................................................................ 6
5.7 Output Voltage Adjustment................................................................................................................................................ 6
6 Bill of Materials....................................................................................................................................................................... 7
7 EVM Assembly Drawing and PCB Layout............................................................................................................................ 9
8 Reference...............................................................................................................................................................................11
9 Revision History....................................................................................................................................................................11
Trademarks
All trademarks are the property of their respective owners.
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TPS51220 Buck Controller Evaluation Module User's Guide 1
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1 Description
The TPS51220 is a dual, peak-current mode, synchronous step-down controller with three low-dropout (LDO)
regulators. It is optimized for 5-V /3.3-V notebook system power supplies. A 99% duty cycle operation enables
designers to complete Li-ion battery applications from 2-cells to 4-cells cost effectively. The TPS51220 supports
high-efficiency, fast transient response and 99% duty cycle operation. DCR current sensing provides lossless
current sensing and free MOSFET selection; resistor sensing supports accurate current-sensing operation. It
supports supply input voltages ranging from 4.5 V to 30 V and output voltages from 1 V to 12 V. High-current, 5
V at 100 mA, 3.3 V at 10 mA, onboard linear regulators have glitch-free switchover function to SMPS, and the
2-V reference has a 100-μA capability.
A peak current-sensing current mode and fixed-frequency control scheme support the full range of current mode
operation including simplified loop compensation, ceramic output capacitors, as well as a seamless transition to
reduced frequency operation at light-load condition.
This evaluation module demonstrates the performance of the high-current/ high-efficiency TPS51220 buck
converter
2 Electrical Performance
SPECIFICATIONS TEST CONDITIONS MIN TYP MAX UNIT
Input voltage range (VIN) 8 12 20 V
CH1 Output voltage 5 V
Operating frequency VIN = 12 V, Iout1 = 6 A 280 kHz
Output current VIN = 8 V to 20 V 6 A
Over current limit VIN = 12 V 9 A
Output ripple voltage VIN = 12 V, Iout1 = 6 A 15 mVp-p
CH2 Output voltage 3.3 V
Operating frequency VIN = 12 V, Iout2 = 6 A 280 kHz
Output current VIN = 8 V to 20 V 6 A
Over current limit VIN = 12 V 9 A
Output ripple voltage VIN = 12 V, Iout2 = 6 A 15 mVp-p
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3 Schematic
+
++
+
+
+
Figure 3-1. HPA302 EVM Schematic Diagram (DCR-Sensing)
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4 Test Setup and Procedure
4.1 Test Setup
Connect test equipment and HPA302-EVM board as shown in Figure 4-1.
HPA302
TPS5122xEVM
CH1
Oscilloscope
TP1
TP2
GNDIVIN
DMM1
+
-
TP7
(VREG5)
TP9
(VREG3)
DMM5
+
-
TP8
(VREF2)
DMM6
+
-
CH2
Oscilloscope
TP12
TP13
DMM3
-
GNDS
SYNC
DMM4
+
-
DMM2
+
-
VOUT1
GND1
GND2
VOUT2
TP14
TP15
Electronic
Load-1
+
-
12 V/10 A
Power
Supply
+
-
Electronic
Load-1
+
-
+
Figure 4-1. Equipment Setup for TPS51220EVM Board
4.2 Test Procedure
1. Ensure that the switches S1 (EN1), S2 (EN2), and S3 (EN) are in OFF position.
2. Ensure that the shunt jumpers for JP1 (TRIP) is set 7-pin to 8-pin (VREG5; Vocl = 60 mV, Discharge-
enabled), JP2 (FUNC) is set 1-pin to 2-pin (GND; UVP/OVP-enabled), and JP3, JP4 are set 3-pin to 4-pin
(VREF2; Auto-skip).
3. Apply appropriate VIN voltage to VIN and GNDI terminals. Check that VREG3 (3.3V-LDO) starts up.
4. Turn S3 (EN) to ON. Check that VREG5 (5V-LDO) and VREF2 (2V-Ref) start up.
5. When S1 (EN1) is turned to ON, CH1-output starts up.
6. When S2 (EN2) is turned to ON, CH2-output starts up.
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5 Configuration
Users can configure this EVM per the following configurations.
5.1 Switching Frequency Selection
The switching frequency can be set by the RF-resistor (R15) or applying external clock into RF pin on the EVM.
Default setting is 280-kHz using RF resistor.
Table 5-1. Switching Frequency Selection
Connection
Internal
Add RF-resistor from RF to GND and be R31 open
[ ]
8
sw
1 10
= [kHz]
RF
f´
W
External Apply external clock signal to SYNC (5 Vpp and 50% duty) , remove R15 in addition, and add
0-Ω to R31.
5.2 Skip Mode and Control Scheme Selection
The skip mode can be set by the SKIPSEL1,2 pins using JP3 and JP4 on the EVM.
Default setting is Auto-skip.
Table 5-2. Skip Mode Selection
Jumper (JP3, JP4) set to SKIPSEL1,2 Skip
Top (1-2 pin shorted) GND CCM
Second (3-4 pin shorted) VREF2 Auto-skip
Third (5-6 pin shorted) VREG3 OOA (<400-kHz)
Bottom (7-8 pin shorted) VREG5 OOA (>400-kHz)
5.3 Current-Sensing Selection
The current-sensing scheme can be set by the external current sensing devices, using some resistors on the
EVM.
Default setting is Inductor DCR sensing
Table 5-3. Current-Sensing Scheme Selection (CH1)
R8 R29 R35 R36 R6 R7 R25
Inductor DCR Put on(1) Put on(1)
(if necessary)
Put on(1) Put on(1) Open Open Open
External Resistor Put on(1) Put on(1)
(if necessary)
Put on(1) Open Put on (1)
Cut trace
Open Open
(1) "Put on” means add appropriate resistor.
Table 5-4. Current Sensing Scheme Selection (CH2)
R18 R28 R33 R37 R20 R19 R26
Inductor DCR Put on(1) Put on(1)
(if necessary)
Put on(1) Put on(1) Open Open Open
External Resistor Put on(1) Put on(1)
(if necessary)
Put on(1) Open Put on (1)
Cut trace
Open Open
(1) "Put on” means add appropriate resistor.
For external resistor sensing, cut the trace as follows.
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Figure 5-1. (CH1) Cut Trace Underneath R6 Figure 5-2. (CH2) Cut Trace Underneath R20
5.4 Overcurrent Limit and Discharge Selection
The overcurrent limit threshold and discharge function can be set by the TRIP pin using JP1 on the EVM.
Default setting is 60 mV and discharge enabled.
Table 5-5. TRIP/ Discharge Mode Selection
Jumper (JP2) set to TRIP VOCL Discharge
Top (1-2 pin shorted) GND 31 mV Enabled
Second (3-4 pin shorted) VREF2 31 mV Disabled
Third (5-6 pin shorted) VREG3 60 mV Disabled
Bottom (7-8 pin shorted) VREG5 60 mV Enabled
5.5 Control Mode and Protection Selection
The control mode and protection function can be set by the FUNC pin using JP2 on the EVM.
Default setting is current mode and UVP/OVP-enabled.
Table 5-6. Control Mode/OVP Selection
Jumper (JP2) set to FUNC Mode OVP
Top (1-2 pin shorted) GND Current Enabled
Second (3-4 pin shorted) VREF2 D-CAP Disabled
Third (5-6 pin shorted) VREG3 D-CAP Enabled
Bottom (7-8 pin shorted) VREG5 Current Disabled
5.6 Soft-Start Setting Selection
Output voltage soft-start time can be set by the ENx pin using some capacitors on the EVM.
Default setting is integrated soft start.
Table 5-7. Soft-Start Setting Selection(1)
CH1 (C20) CH2 (C7)
Integrated soft start Open (adding small bypass-capacitor; 100 pF) Open (adding small bypass-capacitor; 100 pF)
External soft start Put on Put on
(1) When external soft start is selected, add appropriate capacitor on C20 and/or C7.)
5.7 Output Voltage Adjustment
Output voltage is programmable by changing R2, R3, and R5 for CH1 and R21, R23, and R24 for CH2.
Default setting is 5 V for CH1 and 3.3 V for CH2.
Configuration www.ti.com
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R3
V (CH1) =
out
(R5 + R2 + R3) x V (= 1 V)
ref
(1)
When Vout(CH1) is set above 5 V, V5SW input resistor (R22) must be open.
R24
V (CH2) =
out
(R21 + R23 + R24) x V (= 1 V)
ref
(2)
6 Bill of Materials
Table 6-1. Bill of Materials
Reference Qty Description Size Mfr Part Number
C1, C14, C26 3 Capacitor, Ceramic, 10 nF, 50V, X7R, 20% 0603 Std Std
C2, C3 2 Capacitor, SPCAP, 150 μF, 6.3-V, 15-mΩ,
20%
7343 Panasonic EEFCX0J151R
C4, C5, C6, C21,
C22, C23
6 Capacitor, Ceramic, 0.1 μF, 50V, X7R, 20% 0603 TDK C1608X7R1H104K
C7, C16, C20, C27 4 Capacitor, Ceramic, 100 pF, 50V, CH, 5% 0603 TDK C1608CH1H101J
C8, C33 0 Capacitor, Ceramic, 10 μF, 25V, X7R, 20% 1210 – –
C9, C18, C19, C32 4 Capacitor, Ceramic, 10 μF, 25V, X7R , 20% 1210 Murata GRM32DR71E106KA
C10 1 Capacitor, Ceramic, 2.2F, 6.3V, X7R (or
X5R), 10%
0603 Murata
TDK
GRM188R70J225KA
C1608X5R0J225K
C11 0 Capacitor, Ceramic 0603 – –
C12 1 Capacitor, Ceramic, 47pF, 50V, CH, 5% 0603 TDK C1608CH1H470J
C13 1 Capacitor, Ceramic, 0.22F, 50V, X7R, 10% 0630 TDK C1608X7R1E224K
C15 1 Capacitor, Ceramic, 10F, 10V, X7R (or
X5R), 10%
0805 Murata
TDK
GRM21BR71A106K
C2012X5R0J106K
C17 0 Capacitor, Ceramic 0603 – –
C24, C29 0 Capacitor 7343 – –
C25, C30 2 Capacitor, SPCAP, 220F, 4-V, 15-mΩ, 20% 7343 Panasonic EEFCX0G221R
C28 0 Capacitor, Ceramic 0603 – –
C31 0 Capacitor, Ceramic 0603 – –
D1, D2 0 Diode 0.1 × 0.049 inch – –
L1 1 Inductor, 4.7μH, 10.2A, 12.9-mΩ 0.4 × 0.4 inch TOKO FDV1040-4R7M
L2 1 Inductor, 3.3μH, 10.7A, 10.5-mΩ 0.4 × 0.4 inch TOKO FDV1040-3R3M
Q1, Q3 2 MOSFET, N-ch, 30-V, 14-A, 9.7-mΩ SO8 TI CSD17307Q5A
Q2, Q4 2 MOSFET, N-ch, 30-V, 21-A, 4.5-mΩ SO8 TI CSD17310Q5A
R1, R4, R9, R17,
R22, R34, R35,R36,
R37
9 Resistor, Chip, 0Ω, 1/10W, 1% 0603 Std Std
R2 1 Resistor, Chip, 120kΩ, 1/10W, 1% 0603 Std Std
R3 1 Resistor, Chip, 30kΩ, 1/10W, 1% 0603 Std Std
R5, R23 2 Resistor, Chip 49.9 or 51Ω, 1/10W, 1% 0603 Std Std
R6 0 Resistor, Chip, mΩ, 1 W, 1% 3712 Std Std
R7, R25 0 Resistor, Chip 0603 Std Std
R8 1 Resistor, Chip, 7.5kΩ, 1/10W, 1% 0603 Std Std
R10 0 Resistor, Chip 0603 Std Std
R11, R14 2 Resistor, Chip, 470kΩ, 1/10W, 1% 0603 Std Std
R12, R13 2 Resistor, Chip, 10kΩ, 1/10W, 1% 0603 Std Std
R15 1 Resistor, Chip, 360kΩ, 1/10W, 1% 0603 Std Std
R16 0 Resistor, Chip 0603 Std Std
R18, R28 2 Resistor, Chip, 5.6kΩ, 1/10W, 1% 0603 Std Std
R19, R26 0 Resistor, Chip 0603 Std Std
www.ti.com Bill of Materials
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Table 6-1. Bill of Materials (continued)
Reference Qty Description Size Mfr Part Number
R20 0 Resistor, Chip, mΩ, 1 W, 1% 3712 Std Std
R21 1 Resistor, Chip, 62kΩ, 1/10W, 1% 0603 Std Std
R24 1 Resistor, Chip, 27kΩ, 1/10W, 1% 0603 Std Std
R27 0 Resistor, Chip 0603 Std Std
R32 0 Resistor, Chip 0603 Std Std
R29 1 Resistor, Chip, 4.7kΩ, 1/10W, 1% 0603 Std Std
R30, R33 2 Resistor, Chip, 15.4Ω, 1/10W, 1% 0603 Std Std
R31 0 Resistor, Chip 0603 Std Std
R38 1 Resistor, Chip, 0Ω, 1/10W, 1% 0603 Std Std
R39 1 Resistor, Chip, 0Ω, 1/10W, 1% 0603 Std Std
S1, S2, S3 3 Switch, ON-ON Mini Toggle 0.28 × 0.18" Nikkai G12AP
J1, J2 2 Terminal Block, 2-pin, 15A, 5,1mm 0.40 × 0.35inch OST ED1609
JP1, JP2, JP3, JP4 4 Header, 2×4-pin, 100mil spacing (36-pin strip) 0.20 × 0.40inch Sullins PTC36DAAN
— 4 Shunt, 100-mil, Black 0.100 Std Std
TP1, TP2 2 Pin, Probe monitor (VOUT1) 0.12(D) × 0.4 inch Keystone or
MAC8
5002 LC-2-S
TP3, TP10, TP11 3 Pin, Probe monitor (EN, ENx) 0.12(D) × 0.4 inch Keystone or
MAC8
5002 LC-2-S
TP4, TP17 2 Pin, Probe monitor (SW-node) 0.12(D) × 0.4 inch Keystone or
MAC8
5002 LC-2-S
TP5 0 Pin, Probe monitor (IMON) 0.12(D) × 0.4 inch Keystone or
MAC8
5002 LC-2-S
TP6, TP18 2 Pin, Probe monitor (PGOOD) 0.12(D) × 0.4 inch Keystone or
MAC8
5002 LC-2-S
TP7, TP8, TP9 3 Pin, Probe monitor (LDO) 0.12(D) × 0.4 inch Keystone or
MAC8
5002 LC-2-S
TP12, TP13 2 Pin, Probe monitor (VOUT2) 0.12(D) × 0.4 inch Keystone or
MAC8
5002 LC-2-S
TP14, TP15 2 Pin, Probe monitor (VIN) 0.12(D) × 0.4 inch Keystone or
MAC8
5002 LC-2-S
TP16 0 Pin, Probe monitor (IMON) 0.12(D) × 0.4 inch Keystone or
MAC8
5002 LC-2-S
U1 1 IC, Dual Peak Current Mode, Sync. Step-
down Controller
QFN32 TI TPS51220RHB
VIN, GNDI 2 Pin, Wiring Terminal (VIN) 0.12(D) × 0.4 inch Mill Max or
MAC8
3183-2-00-15-00-00-080
or WT-3-1
VOUT1, GND1,
GND3
3 Pin, Wiring Terminal (VOUT1) 0.12(D) × 0.4 inch Mill Max or
MAC8
3183-2-00-15-00-00-080
or WT-3-1
VOUT2, GND2,
GND4
3 Pin, Wiring Terminal (VOUT2) 0.12(D) × 0.4 inch Mill Max or
MAC8
3183-2-00-15-00-00-080
or WT-3-1
SYNC, GNDS 2 Pin, Wiring Terminal (SYNC) 0.12(D) × 0.4 inch Mill Max or
MAC8
3183-2-00-15-00-00-080
or WT-3-1
Bill of Materials www.ti.com
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7 EVM Assembly Drawing and PCB Layout
Figure 7-1. Top Layer/ Assembly
Figure 7-2. Inner Layer 1
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Figure 7-3. Inner Layer 2
Figure 7-4. Bottom Layer/ Assembly
EVM Assembly Drawing and PCB Layout www.ti.com
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