TI TPS65162RGZR

TPS65162
www.ti.com
SLVS771 – MAY 2007
Compact LCD Bias IC With High Speed Amplifiers for TV-LCD Panels
•
•
•
FEATURES
•
•
•
•
•
•
•
8-V to 14.4-V Input Voltage Range
500 kHz / 750 kHz Fixed Switching Frequency
Boost Output Voltage up to 19 V
– 1%-Accurate Boost With 2.8-A Switch
Current Overvoltage Protection
Input-to-Output Isolation Switch for Vs
Short-Circuit protection for Boost
2.5-A Step-Down Converter
Regulated Positive Charge-Pump Driver VGH
Regulated Negative Charge-Pump Driver VGL
Gate Voltage Shaping for VGH
Soft Start for all Converters
Two Integrated High-Speed Opamps
– 50-MHz, 3-dB Bandwidth
– Slew Rate 55 V / µs
– 215-mA Short-Circuit Current
48 Pin 7x7 mm QFN Package
•
APPLICATIONS
•
•
LCD TV
LCD Monitor
DESCRIPTION
The TPS65162 is a compact LCD bias IC with two high-speed operational amplifiers for the Vcom supply. The
high current capability of the device is ideal for large LCD-monitor and LCD-TV applications.
L1
10 mH
AVIN
R1
39 kW
C8
C9
22 mF 22 mF
C7
220 pF
Vs
15 V/1.5 A
C10
22 mF
R2
3.6 kW
D2D3
DRVP
D
S
VIN
VGH
C16
470 nF
C17
470 nF
R5
62 kW
FBP
SS
C12
22 nF
CE
C14
100 pF
Enable Gate
Voltage shaping
VDD
VDPM
SWB
Buck
Converter
FBB
FBN
R4
51 kW
R8
1.5 KW
C20
100 nF
SWB
S
D
DRVN
C18
470 nF
VGH
25 V/50 mA
R7
10 KW
R10
1 KW
CBOOT
D4D5
R3
200 kW
Vs
RE
VFLK
VFLK
R6
3.3 kW
VGHM
Gate Voltage
Shaping
VC
C13
22 nF
C7
470 nF
SWI
SW
SW
FREQ
C12
1 mF
FB
Boost
Converter
EN2
VGL
-5V/50mA
SWO
EN1
PVIN
C4
22 mF
C11
1 mF
C11
1 mF
C5
10 mF
C2
22 mF
PVIN
C1
22 mF
D1
SUP
Vin
8 V to 14 V
L2
10 mH
D5
Vlogic
3.3 V/2.5 A
C21
R11
2.4 kW 470 pF
C22
22 mF
C23
22 mF
REF
DLY1
AGND
PGND3
PGND2
PGND1
POS2
NEG2
C24
10 nF
R12
1.5 kW
DLY2
2
POS1
OUT1
NEG1
OGND
1
OUT2
C19
220 nF
GND
C25
22 nF
Please be aware that an important notice concerning availability, standard warranty, and use in critical applications of Texas
Instruments semiconductor products and disclaimers thereto appears at the end of this data sheet.
PRODUCTION DATA information is current as of publication date.
Products conform to specifications per the terms of the Texas
Instruments standard warranty. Production processing does not
necessarily include testing of all parameters.
Copyright © 2007, Texas Instruments Incorporated
TPS65162
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SLVS771 – MAY 2007
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.
DESCRIPTION (CONTINUED)
The TPS65162 generates all four voltage rails for a TFT LCD (Vs, Vlogic, VGH and VGL) and includes two
op-amps to generate the VCOM supply rail. An input-to-output isolation switch is integrated into the device,
providing short-circuit protection for the boost converter. A current-limit function is implemented in the
input-to-output isolation switch to allow soft turn-on during start-up. The device also features gate voltage
shaping for improved TFT-LCD picture quality. The device consists of a boost converter to provide the source
voltage Vs, and a step-down converter to provide the logic voltage for the system. A positive and a negative
charge-pump driver provide adjustable regulated output voltages VGH and VGL to bias the TFT. Both boost and
buck converter, as well as the charge-pump drivers, operate with a fixed switching frequency of 500 kHz or 750
kHz, selectable by the FREQ pin. The device includes adjustable power-on sequencing. The safety features of
the device are overvoltage protection for boost converter, short-circuit protection for Vs, Vlogic and VGH, and
thermal shutdown.
ORDERING INFORMATION (1)
(1)
TA
ORDERING
QFN PACKAGE
PACKAGE MARKING
–40°C to 85°C
TPS65162RGZR
48 pin QFN
TPS65162
The RGZ package is available taped and reeled and shipped in quantities of 2500 devices per reel.
ABSOLUTE MAXIMUM RATINGS
over operating free-air temperature range (unless otherwise noted) (1)
VI
VALUE
UNIT
Input voltage range VIN, PVIN (2)
–0.3 to 16.8
V
Voltage range at EN1, EN2, FREQ, VDPM, VFLK
Voltage on pin
– 0.3 to 16.8
V
AVIN, SUP
25
V
VGH, VGHM, RE
35
V
SW, SWI, SWO
25
V
SWB
20
V
Continuous total power dissipation
See Dissipation Rating Table
TJ
Operating junction temperature range
–40 to 150
°C
TA
Operating ambient temperature range
–65 to 85
°C
Tstg
Storage temperature range
–65 to 150
°C
(1)
(2)
Stresses beyond those listed under absolute maximum ratings may cause permanent damage to the device. These are stress ratings
only, and functional operation of the device at these or any other conditions beyond those indicated under recommended operating
conditions is not implied. Exposure to absolute-maximum-rated conditions for extended periods may affect device reliability.
All voltage values are with respect to network ground terminal.
DISSIPATION RATINGS (1)
(1)
PACKAGE
RθJA
TA ≤ 25°C POWER RATING
TA = 70°C POWER RATING
TA = 85°C POWER RATING
48 pin QFN
30°C/W
3.33 W
1.83 W
1.33 W
Exposed thermal die is soldered to the PCB using thermal vias. Refer to Texas Instruments Application report (SLUA271) QFN/SON
PCB Attachment.
RECOMMENDED OPERATING CONDITIONS
MIN
2
VIN, PVIN
Input voltage range
TA
Operating ambient temperature
TJ
Operating junction temperature
MAX
UNIT
14.4
V
–40
85
°C
–40
125
°C
8
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SLVS771 – MAY 2007
ELECTRICAL CHARACTERISTICS
Vin=12 V, EN1=EN2=FREQ=high, Vs=15 V, Vlogic=3.3 V ,TA = –40°C to 85°C, typical values are at TA = 25°C (unless
otherwise noted)
PARAMETER
TEST CONDITIONS
MIN
TYP
MAX
UNIT
14.4
V
SUPPLY CURRENT
VI
ISD
Input voltage range
8
Shutdown current into VIN
EN1=EN2=GND
0.03
1
Shutdown current into PVIN
EN1=EN2=GND
0.01
1
µA
IQIN
Quiescent current into VIN
1.7
4
mA
ISUP
Shutdown current into SUP
EN1=EN2=GND
0.01
1
µA
Shutdown current into AVIN
EN1=EN2=GND
50
220
µA
8
10
mA
IAVIN
Quiescent current into AVIN
VUVLO
Undervoltage lockout threshold
VREF
Reference voltage
Thermal shutdown
Vin falling
1.253
Temperature rising
Thermal shutdown hysteresis
7.6
7.95
1.265
1.277
V
V
160
°C
10
°C
LOGIC SIGNALS EN1, EN2, FREQ, VFLK, VDPM
VIH
High level input voltage EN1, EN2, VDPM,
FREQ
VIL
Low level input voltage EN1, EN2, VDPM,
FREQ
VIH
High level input voltage VFLK
VIL
lOW level input voltage VFLK
II
Input leakage current
2.0
V
0.8
1.7
EN1=EN2=FREQ=VFLK=VDPM=GND or VIN
V
V
0.01
0.4
V
0.1
µA
CONTROL AND SOFT START DLY1, DLY2, SS
Ichrg
DLY1, DLY2 charge current
ISS
SS charge current
Vthr
Delay threshold
Vthreshold = 1.280 V
3.5
5
6
6
9.2
12
1.280
µA
V
INTERNAL OSCILLATOR
fosc
Oscillator frequency
FREQ = high
600
750
900
FREQ = low
400
500
600
1.255
1.268
1.280
V
10
100
nA
130
200
mΩ
9
15
Ω
1
A
kHz
BOOST CONVERTER (Vs)
VS
Output voltage range
VFB
Feedback regulation voltage
IFB
Feedback input bias current
RDS(on)
19
N-MOSFET on-resistance (Q1)
Vs = 15 V, I(SW) = 500 mA
P-MOSFET on-resistance (Q2)
Vs = 15 V,I(SW) = 200 mA
IMAX
Maximum P-MOSFET peak switch current
ILIM
N-MOSFET switch current limit (Q1)
Ileak
Switch leakage current
V(SW) = 15 V
Vswovp
Switch overvoltage protection
Vout rising
Line Regulation
8V≤Vin≤14V, Iout = 2mA
Load Regulation
2.8
19.5
V
3.6
4.2
A
1
10
µA
20
21
V
0.007
%/V
2mA≤Iout≤1.5A
0.03
%/A
ISW = 1 A, Vs = 15 V
200
ISOLATION SWITCH
RDSon
Isolation switch RDSon
I
Switch current
ISC
Short circuit current limit
mΩ
2
SWI = 12V, SWO = 0V
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A
mA
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SLVS771 – MAY 2007
ELECTRICAL CHARACTERISTICS (continued)
Vin=12 V, EN1=EN2=FREQ=high, Vs=15 V, Vlogic=3.3 V ,TA = –40°C to 85°C, typical values are at TA = 25°C (unless
otherwise noted)
PARAMETER
TEST CONDITIONS
MIN
TYP
MAX
UNIT
GATE VOLTAGE SHAPING VGHM
VHVIN
Input voltage
35
VGH to VGHM RDSon (Q1)
VFLK = high, I = 20 mA
10
15
VGHM to RE RDSon
VFLK = LOW, I = 20 mA
60
100
ICE
CE capacitor charge current
VCE = 1.265 V
57
65
VCE
CE threshold voltage
GVDD
VDD voltage gain
RDSon
44
1.284
VVDD = 1 V
V
Ω
µA
V
5
V/V
STEP-DOWN CONVERTER (Vlogic)
Vlogic
Output voltage range
VFB
Feedback regulation voltage
1.5
IFB
Feedback input bias current
RDS(on)
N-MOSFET on-resistance (Q1)
ILIM
N-MOSFET switch current limit (Q1)
Ileak
Switch leakage current
V(SW) = 0 V
Line regulation
8V≤Vin≤14V, Iout = 2mA
Load regulation
2mA≤Iout≤2.5A
5
1.240
PVIN = 12 V, I(SW) = 500 mA
2.8
V
1.265
1.290
V
10
100
nA
180
320
mΩ
3.6
4.2
A
1
10
µA
0.006
%/V
0.06
%/A
NEGATIVE CHARGE PUMP VGL
VGL
Output voltage range
VFB
Feedback regulation voltage
IFB
Feedback input bias current
RDS(on)
Q4 P-Channel switch RDSon
VDropN
Current source voltage drop (1)
Load regulation
-2
V
0
48
mV
10
100
nA
4
8
Ω
I(DRVN) = 50 mA, V(FBN) = V(FBNnominal)– 5%
115
200
I(DRVN) = 100 mA, V(FBN) = V(FBNnominal)– 5%
230
400
1 mA ≤ IO ≤ 100 mA, VGL = –5 V
0.01
–48
IO = 20 mA
mV
%/mA
POSITIVE CHARGE PUMP OUTPUT VGH
VGH
Output voltage range
VFB
Feedback regulation voltage
IFB
Feedback input bias current
RDSon
Q3 N-Channel switch RDSon
VDropP
Current source voltage drop (Vsup–VDRP)(1)
Load regulation
34
1.228
1.302
V
10
100
nA
Ω
IOUT = 20 mA
1.0
1.8
IDRP = 50 mA, VFBP = VFBPnominal– 5%
430
680
IDRP = 100 mA, VFBP = VFBPnominal– 5%
950
1600
1 mA ≤ Iout ≤ 50 mA, VGH = 27 V
V
1.265
0.073
mV
%/mA
OPERATIONAL AMPLIFIERS 1, 2
Vos
Input offset voltage
VCM = Vs/2
IB
Input bias current
VCM = Vs/2
VCM
Common Mode Input Voltage Range
CMRR
Common Mode Rejection Ratio
VCM = 7.5 V
70
AVOL
Open Loop Gain
0.5 V ≤ VOUT≤ 14.5 V, No load
50
VOL
Output Voltage Swing Low
IOUT = 10 mA
VOH
Output Voltage Swing High
IOUT = 10 mA
Isc
Short Circuit Current
Io
Output Current
PSRR
Power Supply Rejection Ratio
SR
Slew Rate
BW
– 3db Bandwidth
GBWP
Gain Bandwidth Product
(1)
4
–15
0.05
0
VOUT = 7.5 V , Input offset voltage 10 mV
18
mV
3
µA
Vs
V
dB
dB
60
200
mV
Vs-200
Vs-100
mV
120
215
mA
90
170
mA
80
dB
AV = 1, VIN = 2 Vpp
55
V/µs
AV = 1, VOUT = 60 mVpp
50
MHz
36
MHz
The maximum charge pump output current is typically one-half the drive current of the internal current source.
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SLVS771 – MAY 2007
OUT2
POS2
NEG2
AVIN
SWO
FB
NC
SWI
1 48
47
46
45
44
43
42
41
40
39
OUT1
SW
OGND
POS1
SW
NEG1
PIN ASSIGNMENT
Top View
38
3736
PGND3
2
35
PGND2
VDD
3
34
PGND1
CE
4
33
EN1
VFLK
5
32
EN2
VDPM
6
31
VC
30
SS
Exposed
Thermal Pad
28
FREQ
FBP
10
27
VIN
GND
11
26
PVIN
25
PVIN
16
17
18
19
20
NC
15
AGND
14
DRVN
12
13
SUP
DRVP
21
22
23
24
SWB
9
SWB
VGH
CBOOT
DLY2
FBB
29
NC
8
DLY1
VGHM
REF
7
FBN
RE
NOTE: The thermally-enhanced PowerPAD is connected to PGND1 (Device power Ground). NC pin is internally not
connected.
TERMINAL FUNCTIONS
TERMINAL
I/O
DESCRIPTION
NAME
NO.
POS1
1
I
Non inverting input of Operational Amplifier 1
OUT1
2
O
Output of Operational Amplifier 1.
VDD
3
I
Threshold voltage of gate voltage shaping. The five times of voltage applied to this pin set the threshold
discharge voltage for the gate voltage shaping function
CE
4
I
Delay of gate voltage shaping. Sets the delay between the falling edge of VFLK to the falling edge of VGHM
VFLK
5
I
Control of gate voltage shaping.
VDPM
6
I
Enable of gate voltage shaping block.
RE
7
O
Slope adjustment of gate voltage shaping. Connecting a resistor to this pin allows to adjust the slop of gate
voltage shaping.
VGHM
8
O
Output of the gate voltage shaping block.
VGH
9
I
High voltage for gate voltage shaping block. Connect the output of the positive charge pump to this pin.
FBP
10
I
Feedback of the positive charge pump.
GND
11
DRVP
12
O
Drive pin of the positive charge pump.
SUP
13
I
Supply pin of the positive charge pump
DRVN
14
O
Drive pin of the negative charge pump
AGND
15
FBN
16
Ground for positive and negative charge pump.
Analog ground
I
Feedback of the negative charge pump.
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TERMINAL FUNCTIONS (continued)
TERMINAL
NAME
6
NO.
I/O
DESCRIPTION
REF
17
O
Internal reference output. Connect 220-nF capacitor directly from this pin to AGND to minimize possible noise
coupling into the reference of the IC.
DLY1
18
O
Connecting a capacitor from this pin to GND allows setting the delay time between the step down converter
and negative charge pump VGL
NC
19, 20,
40
FBB
21
I
Feedback of the buck converter.
CBOOT
22
I
N-channel MOSFET gate drive voltage for the buck converter. Connect a capacitor from this pin to SWB.
SWB
23, 24
O
Switch pin of the buck converter
PVIN
Not connected.
25, 26
I
Power input for the buck converter.
VIN
27
I
Analog input voltage of the device. This pin should be bypassed with a 1-µF capacitor for good filtering.
FREQ
28
I
Frequency selection pin. With FREQ=high, the device operates with 750 kHz. With FREQ=low, the device
operates with 500kHz.
DLY2
29
O
Connecting a capacitor from this pin to GND allows setting the delay time between the step down converter
and positive charge pump VGH.
SS
30
O
soft-start of the boost converter. Connect a capacitor from this pin to GND.
VC
31
O
Compensation pin of the boost converter.
EN2
32
I
Enable pin of the boost converter block.
EN1
33
I
Enable pin of the buck converter and negative charge pump. When this pin is pulled high, the buck converter
starts up, and after a delay time set by DLY1, the negative charge pump starts up. A logic high enables the
device and a logic low shut down the device.
PGND1
34
PGND2
35
PGND3
36
Power ground.
Ground for boost converter.
SW
37, 38
I
Switch pin of the boost converter
SWI
39
I
Input of the isolation switch. The SWI pin is connected to internal overvoltage protection comparator.
FB
41
I
Feedback of the boost converter generating Vs
SWO
42
O
Output of the isolation switch
AVIN
43
I
Power input voltage pin for Operational Amplifier. Bypass this pin with a 1-µF bypass capacitor
NEG2
44
I
Inverting input of Operational Amplifier 2
POS2
45
I
Non inverting input of Operational Amplifier 2
OUT2
46
O
Output of Operational Amplifier 2
OGND
47
NEG1
48
Ground for Operational Amplifier.
I
Inverting input of Operational Amplifier 1
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FUNCTIONAL BLOCK DIAGRAM
L1
10 mH
AVIN
R1
39 kW
C8
C9
22 mF 22 mF
C7
220 pF
Vs
15 V/1.5 A
C10
22 mF
R2
3.6 kW
D2D3
DRVP
D
S
VIN
VGH
C16
470 nF
C17
470 nF
R5
62 kW
FBP
SS
C12
22 nF
CE
C14
100 pF
Enable Gate
Voltage shaping
VDD
VDPM
SWB
Buck
Converter
C18
470 nF
FBB
FBN
R4
51 kW
R8
1.5 KW
C20
100 nF
SWB
S
D
DRVN
VGH
25 V/50 mA
R7
10 KW
R10
1 KW
CBOOT
D4D5
R3
200 kW
Vs
RE
VFLK
VFLK
R6
3.3 kW
VGHM
Gate Voltage
Shaping
VC
C13
22 nF
L2
10 mH
D5
Vlogic
3.3 V/2.5 A
C21
R11
2.4 kW 470 pF
C22
22 mF
C23
22 mF
REF
DLY1
AGND
PGND3
PGND2
PGND1
POS2
NEG2
C24
10 nF
R12
1.5 kW
DLY2
2
POS1
OUT1
NEG1
1
OUT2
C19
220 nF
OGND
C7
470 nF
SWI
SW
SW
FREQ
C12
1 mF
FB
Boost
Converter
EN2
VGL
-5V/50mA
SWO
EN1
PVIN
C4
22 mF
C11
1 mF
C11
1 mF
C5
10 mF
C2
22 mF
PVIN
C1
22 mF
D1
SUP
Vin
8 V to 14 V
GND
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C25
22 nF
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TYPICAL CHARACTERISTICS
Table of Graphs
FIGURE
Main Boost Converter (Vs)
η
Efficiency
vs Load current
Figure 1
Soft start
Figure 2
PWM operation
at nominal load current
Figure 3
PWM operation
at light load current
Figure 4
Load transient response
Figure 5
Short-circuit protection
Figure 6
Overvoltage protection
Figure 7
Step-Down Converter (Vlogic)
η
Efficiency
vs Load current
Figure 8
PWM operation
at nominal load current
Figure 9
PWM operation
at light load current
Figure 10
Soft start
Figure 11
Load transient response
Figure 12
System Performance
Powerup sequencing
EN2 connected to VIN
Figure 13
Powerup sequencing
EN2 enabled separately
Figure 14
Gate voltage shaping
Figure 15
Negative Charge Pump Driver
VGL
vs VGL Load current
Figure 16
VCOM BUFFERS
–3 dB bandwidth, opamp
Figure 17
Slew rate, opamp
Figure 18
BOOST CONVERTER (Vs)
η EFFICIENCY
vs
LOAD CURRENT
SOFT-START
100
VI = 14 V
90
VO
10 V/div
VI = 12 V
VI = 8 V
80
Efficiency - %
VI = 12 V,
VO = 15 V/1.2 A
C(SS) = 22 nF
VSW
10 V/div
70
60
VS = 15 V,
VGH, VGL, VLOGIC no Load Switching
OpAmp no Load Operating
50
II
1 A/div
40
0
0.5
1
IO - Output Current - A
1.5
Figure 1.
8
2.5 ms/div
Figure 2.
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PWM OPERATION AT NOMINAL
LOAD CURRENT
PWM OPERATION, LIGHT
LOAD CURRENT
VI = 12 V,
VO = 15 V/1.5 A
VI = 12 V,
VO = 15 V/10 mA
VSW
10 V/div
VSW
10 V/div
VO
50 mV/div
VO
50 mV/div
IL
1 A/div
IL
500 mA/div
1 ms/div
1 ms/div
Figure 3.
Figure 4.
LOAD TRANSIENT RESPONSE
SHORT CIRCUIT PROTECTION
VI = 12 V,
VO = 15 V
Output shorted
VO
200 mV/div
VO
5 V/div
IL
500 mA/div
IO
500 mA/div
VI = 12 V,
VO = 15 V/div
500 ms/div
100 ms/div
Figure 5.
Figure 6.
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OVERVOLTAGE PROTECTION
VSW
10 V/div
VO
2 V/div
VI = 12 V,
VO = 15 V/100 mA
IL
2 A/div
500 ms/div
Figure 7.
STEP-DOWN CONVERTER (Vlogic)
η EFFICIENCY
vs
LOAD CURRENT
PWM OPERATION, NOMINAL
LOAD CURRENT
90
Efficiency - %
80
VI = 8 V
VI = 12 V
VI = 14 V
70
VSW
5 V/div
60
VO
20 mV/div
50
VLOGIC = 3.3 V,
VS, VGH, VGL No Load Switching
OpAmp No Load, Operating
IL
1 A/div
40
0
0.5
1
1.5
IO - Output Current - mA
2
2.5
Figure 8.
10
VI = 12 V,
VO = 3.3 V/1.5 A
500 ns/div
Figure 9.
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PWM OPERATION, LIGHT
LOAD CURRENT
SOFT START
VI = 12 V,
VO = 3.3 V/45 mA
VI = 12 V,
VO = 3.3 V/1.2 A
VSW
5 V/div
VO
1 V/div
VO
20 mV/div
IL
1 A/div
IL
200 mA/div
500 ms/div
500 ns/div
Figure 10.
Figure 11.
LOAD TRANSIENT RESPONSE
VI = 12 V,
VO = 3.3 V
VO
100 mV/div
IO
1 A/div
100 ms/div
Figure 12.
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SYSTEM PERFORMANCE
POWERUP SEQUENCING
vs
EN2 CONNECTED TO VIN
POWERUP SEQUENCING
vs
EN2 ENABLED SEPARATELY
VLOGIC
2 V/div
VLOGIC
2 V/div
VS
5 V/div
VS
5 V/div
VGH
10 V/div
VGH
10 V/div
VGL
5 V/div
EN2
10 V/div
2.5 ms/div
2.5 ms/div
Figure 13.
Figure 14.
GATE VOLTAGE SHAPING
VGHM
10 V/div
VDD = 2 V,
RE = 33 kW,
VGH = NO LOAD
IO
2 V/div
5 ms/div
Figure 15.
12
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NEGATIVE CHARGE PUMP DRIVER
VGL
vs
VGL LOAD CURRENT
-4.94
VS = 15 V,
VGL = -5 V
-4.96
TA = 85°C
VGL - V
-4.98
-5
TA = -40°C
-5.02
TA = 25°C
-5.04
-5.06
-5.08
-5.10
0
10
20
30 40 50 60 70 80
IO - Output Current - mA
90
100
Figure 16.
VCOM BUFFERS
Magnitude - dB
–3-dB BANDWIDTH, OPAMP
SLEW RATE, OPAMP
Output: No load
0 dB
1 dB/div
IN
1 V/div
OUT
1 V/div
1
10
f - Frequency - MHz
100
Figure 17.
Output: no load
Input: 1.6 V Step
10 ns/div
Figure 18.
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APPLICATION INFORMATION
THERMAL SHUTDOWN
The thermal-shutdown feature prevents damage from excessive heat and power dissipation. Typically, the
thermal-shutdown threshold is 160°C. When the temperature drops below the thermal shutdown threshold, the
device restarts again automatically.
UNDERVOLTAGE LOCKOUT
To avoid device malfunction at low input voltages, an undervoltage lockout is included, which shuts down the
device at voltages lower than 7.6 V.
REFERENCE OUTPUT, REF
The device provides a reference output that is used to regulate the negative charge pump. In order to have a
stable reference voltage, a 220-nF bypass capacitor is required, connected directly from REF to AGND. The
reference output has a current capability of 30 µA which should not be exceeded. Because of this, the feedback
resistor from FBN to REF should not be smaller than 40 kΩ.
START-UP SEQUENCING
The start-up sequencing can be set by adjusting the capacitors connected to DLY1 and DLY2, and is controlled
by the signals EN1 and EN2. Pulling EN1 high enables the step-down converter. After the step down converter
has reached its power-good threshold, the other sequence timings are started. DLY1 sets the delay time
between the step-down converter and the negative charge-pump driver. This delay starts when the power-good
threshold of the step-down converter is reached. A high level on EN2 enables the boost converter. The boost
converter starts when the power-good threshold of the step down converter is reached and EN2 is pulled high.
DLY2 sets the delay time for the positive charge pump. This delay time starts when the power good threshold of
the step down converter is reached. After the delay time has expired, the positive charge pump and op-amps
start up. As the positive charge pump power-good threshold is reached, then the GPM block is enabled if VDPM
is high as well. See Figure 19.
EN1
EN2
DLY 2
VGHM
with VFLK
=high,
VDPM=high
Vs
Fall time depends on output
capacitors value and load current
V logic
VGL
DLY 1
Figure 19. Power-On Sequencing With EN2 Always High (EN2=VIN)
14
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APPLICATION INFORMATION (continued)
If EN2 goes high after the step down converter is already enabled, then the delay DLY2 starts when EN2 goes
high. See Figure 20.
EN1
EN2
DLY 2
VGHM
with VFLK
=high,
VDPM=high
Vs
Fall time depends on output
capacitors value and load current
Vlogic
VGL
DLY 1
Figure 20. Power-on Sequencing Using EN1 and EN2
SETTING THE DELAY TIMES DLY1, DLY2
Connecting an external capacitor to the DLY1 and DLY2 pin sets the delay time. If no delay time is required
these pins can be left open. To set the delay time the external capacitor connected to DLY1 and DLY2 is
charged with a constant current source of typically 5 µA. The delay time is terminated when the capacitor
voltage has reached the internal reference voltage of VREF=1.280 V. The external delay capacitor is calculated
using Equation 1:
5 mA ´ t d 5 mA ´ t d
C dly =
=
VREF
1.280 V
(1)
where td = Desired delay time
Example for setting a delay time of 5.3 ms:
5 mA 5.3 ms
C dly +
+ 20.7 nF [ 22 nF
1.280 V
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APPLICATION INFORMATION (continued)
BOOST CONVERTER
The TPS65162 boost converter block is shown in Figure 21. The boost converter operates with PWM (Pulse
Width Modulation) at a fixed switching frequency of 500 kHz or 750 kHz, selected by the FREQ pin. The
converter uses an unique fast-response, voltage-mode controller scheme with input-voltage feedforward. This
achieves excellent line and load regulation (0.03%/A load regulation typical), and allows the use of small
external components. To add more flexibility to the selection of external component values, the device uses
external loop compensation. Although the boost converter looks like a non-synchronous boost converter
topology operating in discontinuous-conduction mode under a light load, the TPS65162 remains in
continuous-conduction mode even under light load currents. (Figure 4) This is achieved with a novel architecture
using an external Schottky diode with an integrated MOSFET in parallel connected between the SW pin and the
SUP pin. This MOSFET allows the current to go below ground, which is the case under light load conditions. For
this use, a small integrated P-Channel MOSFET (Q2) with typically 9 Ω RDSon is sufficient. When the inductor
current is positive, the external Schottky diode, with the lower forward voltage, carries the current. This causes
the converter to operate with a fixed frequency in continuous-conduction mode over the entire load-current
range. This avoids ringing on the switch pin as seen with a standard non-synchronous boost converter, and
allows a simpler compensation circuit for the boost converter.
VIN
FREQ
SW
SWI
SW
SWO
IDLY
D
Vref
SS
Control logic
EN
D
S
S
Q2
D
EN
Clock
COMP
500kHz/
750KHz
Oszillator
Comparator
Control Logic
D
S
Q1
Sawtooth
Generator
FB
PGND2
Overvoltage
Comparator
OVP
VFB
1.268V
GM Amplifier
Low Gain
Vref
VFB
1.268V
SUP
Current limit
and
Soft Start
GM Amplifier
SUP
Figure 21. Boost Converter Block TPS65162
16
S
Vds Sensor
Soft start
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APPLICATION INFORMATION (continued)
Soft Start
To minimize inrush current during startup, the boost converter has an adjustable soft-start, and the
input-to-output isolation switch has current-limit control. The current limit of the input-to-output isolation switch is
slowly ramped up for a soft turn-on. The VDS sensor of the input-to-output isolation switch monitors the voltage
difference between SWI and SWO, and controls the current through the isolation switch. With VDS = 12 V, the
current-limit threshold through the isolation switch is typically 330 mA. This current-limit threshold will linearly
increase by factor of two till VDS reaches 3 V; current limiting is disabled when VDS is below 3 V. The boost
converter is enabled when VDS is below 0.5 V. An external capacitor connected to the soft-start pin, SS, is used
to slowly ramp up the internal switch current limit of the boost converter. The capacitor connected to the SS pin
is charged with a constant current that increases the voltage on the SS pin. The internal current limit is
proportional to the voltage on the SS pin. When the threshold voltage of the internal-switch soft-start comparator
is reached, the full current limit is released. The larger the soft-start capacitor value, the longer the soft-start
time. A 22-nF capacitor is usually sufficient for typical applications.
Overvoltage Protection
The boost converter has an overvoltage-protection circuit to prevent the switch voltage from exceeding the
absolute-maximum switch voltage rating in the event of a system fault. The device protects itself if the feedback
pin is connected to ground or floated, and clamps the voltage of the output of the boost converter to 20 V. To
implement the overvoltage protection, the overvoltage comparator shown in Figure 21 monitors the output
voltage via the SWI pin. As soon as the output voltage exceeds the overvoltage threshold (typically 20 V), the
device stops switching until the output voltage drops below the comparator threshold again. The typical
waveform when the device is in overvoltage protection is shown in Figure 7.
Short CIrcuit Protection
The boost converter has a short-circuit protection circuit to prevent the inductor or rectifier diode from
overheating when the output is shorted. The VDS sensor in the input-to-output isolation switch monitors the
voltage difference between SWI and SWO. If the boost output is shorted, and the voltage difference between
SWI and SWO exceeds the threshold (typically 1.4 V in full operation), then the boost converter shuts down, and
the input-to-output isolation switch limits VS current.
Input Capacitor Selection (VIN, SUP)
Low ESR ceramic capacitors are recommended for good input-voltage filtering. The TPS65162 has an analog
input (VIN) as well as a power supply input (SUP) powering all the internal rails. A 1-µF bypass capacitor is
required as close as possible from VIN to GND, and from SUP to GND. Depending on the overall load current,
two or three 22-µF input capacitors are required. For better input-voltage filtering, the input capacitor values can
be increased. Refer to Table 1 and the Typical Applications schematic for input capacitor recommendations.
Table 1. Input Capacitor Selection
CAPACITOR
COMPONENT SUPPLIER
COMMENTS
22 µF / 16 V
Taiyo Yuden EMK316BJ226ML
Pin VIN, PVIN
2 ×10 µF / 25 V
Taiyo Yuden TMK316BJ106KL
Pin VIN, PVIN (Alternative)
1 µF / 35 V
Taiyo Yuden GMK107BJ105KA
Pin SUP, AVIN, VIN
1 µF / 25 V
Taiyo Yuden TMK107BJ105KA
Pin SUP, AVIN, VIN
Frequency Select Pin, FREQ
The frequency-select pin FREQ selects the switching frequency of the entire device to 500 kHz (FREQ=low) or
750 kHz (FREQ=high). A lower switching frequency gives a higher efficiency with a slightly reduced
load-transient regulation.
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Boost Converter Design Procedure
The first step in the design procedure is to verify whether the maximum possible output current of the boost
converter supports the specific application requirements. To simplify the calculation, the fastest approach is to
estimate the converter efficiency, by taking the efficiency numbers from the provided efficiency curves, or to use
a worst-case assumption for the expected efficiency, e.g., 80%. With the efficiency number it is possible to
calculate the steady-state values of the application.
Vin h
Vout
1. Converter Duty Cycle:
D +1*
2. Maximum output current:
Iout + Isw * Vin D
2 ƒs L
3. Peak switch current:
I
I swpeak + Vin D ) out
2 ƒs L 1 * D
ǒ
Ǔ
(1 * D)
With Isw = converter switch current (minimum switch current limit = 2.8 A)
ƒs = converter switching frequency (typical 500kHz or 750 kHz)
L = Selected inductor value
η = Estimated converter efficiency (use the number from the efficiency curves or 0.8 as an estimation)
The peak switch current is the steady-state peak switch current that the integrated switch, inductor and external
Schottky diode must be able to handle. The calculation must be done for the minimum input voltage where the
peak switch current is highest.
Inductor Selection
The TPS65162 typically operates with a 10-µH inductor. The main parameter for inductor selection is the
inductor saturation current, which should be higher than the peak switch current, as calculated above, with
additional margin to handle heavy load transients. An alternative more conservative approach is to choose an
inductor with a saturation current at least as high as the typical switch current limit of 3.6 A. The second
important parameter is the inductor DC resistance. Usually, the lower the DC resistance, the higher the
efficiency of the converter. The choice of inductor can affect converter efficiency by as much as 10%. Example
inductors are shown in Table 2.
Table 2. Inductor Selection (Boost Converter)
INDUCTOR VALUE
COMPONENT SUPPLIER
DIMENSIONS in mm
Isat/DCR
10 µH
Coilcraft DO3316P-103
12.95 × 9.4 × 5.51
3.9 A / 38 mΩ
10 µH
Sumida CDRH8D43-100
8.3 × 8.3 × 4.5
4.0 A / 29 mΩ
10 µH
Wuerth Elektronik 744066100
10 × 10 × 3.8
4.0 A / 25 mΩ
Output Capacitor
For best output-voltage filtering, a low-ESR output capacitor is recommended. Ceramic capacitors have a low
ESR value and work best with the TPS65162. One 10-µF ceramic output capacitor before the input-to-output
isolation switch, SWI, and six 10-µF or three 22-µF ceramic output capacitors in parallel after the input-to-output
isolation switch, SWO, are sufficient for most applications. To improve the load transient regulation, add more
capacitors after the input-to-output isolation switch. Refer to Table 3 for the selection of the output capacitor.
Table 3. Output Capacitor Selection
18
CAPACITOR
COMPONENT SUPPLIER
10 µF/25 V
Taiyo Yuden TMK316BJ106KL
22 µF/25 V
TDK C4532X7R1E226M
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Rectifier Diode Selection
To achieve high efficiency, a Schottky diode should be used. The reverse voltage rating should be higher than
the maximum output voltage of the converter. The current rating for the Schottky diode is calculated as the off
time of the converter times the typical switch current of the TPS65162:
V
Iavg = (1 - D) × ISW = in ´ 3.6 A
Vout
(3)
where ISW=typical switch current of the TPS65162 (3.6 A)
A Schottky diode with 2-A maximum average rectified forward current rating is sufficient for most applications.
The Schottky rectifier must have adequate power dissipation. The dissipated power is the average rectified
forward current times the diode forward voltage.
PD = Iavg × VF = ISW × (1 - D) × VF
(4)
where ISW=typical switch current of the TPS65162 (3.6 A)
Table 4. Rectifier Diode Selection (Boost Converter)
Iavg
Vr
Vforward
RθJA
SIZE
COMPONENT SUPPLIER
3A
2A
20 V
0.36 at 3 A
46°C/W
SMC
MBRS320, International Rectifier
20 V
0.44 V at 2 A
75°C/W
SMB
2A
SL22, Vishay Semiconductor
20 V
0.5 at 2 A
75°C/W
SMB
SS22, Fairchild Semiconductor
Setting the Output Voltage and Selecting the Feedforward Capacitor
The output voltage is set by the external resistor divider and is calculated as:
V out + 1.268 V
ǒ1 ) R1
Ǔ
R2
(5)
Across the upper resistor a bypass capacitor is required to speed up the circuit during load transients. The
capacitor is caluculated as:
1
C ff =
2 × p × f z × R1
(6)
Depending on the inductor value, the zero frequency needs to be set. fz is 19 kHz for a 10 µH inductor, and 9
kHz for a 22 µH inductor. A value coming closest to the calculated value should be used.
Compensation (VC)
The regulator loop can be compensated by adjusting the external components connected to the VC pin. The VC
pin is the output of the internal transconductance error amplifier. A single capacitor connected to this pin sets the
low frequency gain. A 22-nF capacitor is usually sufficient for most applications.
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POSITIVE CHARGE PUMP
The positive charge pump provides a regulated output voltage set by the external resistor divider. The
TPS65162 positive charge pump block is shown in Figure 22.
SUP
500 kHz/
750 KHz
Oscillator
IDRVP
Current
Control
Softstart
DRVP
Q5
GND
Vref
1.265V
FBP
Figure 22. Positive Charge Pump Block TPS65162
Since the flying capacitor-voltage sits on top of the drive-pin voltage, the maximum output voltage is VSUP+VS–
Vdrop. Vdrop is the voltage drop across the external diodes and internal charge pump MOSFETs. If higher output
voltages are required, another charge pump stage can be added to the output.
Setting the output voltage:
V out + VREF
ǒ1 ) R5
Ǔ + 1.265 V ǒ1 ) R5
Ǔ
R6
R6
(7)
To minimize noise and leakage current sensitivity, we recommend a value of approximately 20 kΩ for the lower
feedback divider resistor R6.
20
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NEGATIVE CHARGE PUMP
The negative charge pump provides a regulated output voltage set by the external resistor divider. The
TPS65162 negative charge pump block is shown in Figure 23. The negative charge pump operates very similar
to the positive charge pump, with the difference that it runs from the input voltage VIN. The maximum negative
output voltage is VGL=(–VIN)+Vdrop. Vdrop is the voltage drop across the external diodes and internal
charge-pump MOSFETs.
The output voltage is calculated by:
V out + *VREF R3 + *1.265 V
R4
R3
R4
(8)
Since the reference-output driver current should not exceed 30uA (typical), the lower feedback resistor value R4
should be in a range of 40 kΩ to 120 kΩ. Overall feedback resistance should be in the range from 500 kΩ to 1
MΩ. The negative charge pump requires two external Schottky diodes. The peak current rating of the Schottky
diode must be twice the load current of the output. For a 20-mA output current, the dual Schottky diode BAV99
is a good choice.
VIN
500 kHz/
750 KHz
Oscillator
Q7
DRVN
Control
Logic
Softstart
IDRVN
GND
FBN
Vref
0V
Figure 23. Negative Charge Pump Block TPS65162
GATE VOLTAGE SHAPING
The gate voltage shaping reduces the flickering effect of an LCD panel, and isolates VGHM from the source
voltage VGH. For correct operation of this block, it is not recommend to connect an output capacitor to VGHM.
To reduce the voltage ripple on VGHM, add more capacitors on VGH. The TPS65162 gate voltage shaping
block is shown in Figure 24. The corresponding timing diagram is shown in Figure 26. The gate voltage shaping
block responds to VFLK under the following conditions:
• The device is enabled with VDPM = high
• The input voltage is above the undervoltage lockout
• The positive charge pump is in regulation
When VGH is pulled below its power-good level, Q1 and Q2 are turned off and VGHM is discharged via the
1-kΩ resistor over Q3. With VFLK = high, Q1 and Q4 are turned on and Q2 is turned off. VGH is present at
VGHM when Q1 is on, and at the same time, the capacitor connected to the CE pin is discharged by Q4 to
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GND. When VFLK is taken low, Q4 is turned off, and the capacitor connected to the CE pin is charged by a
constant current source, typically 60 µA. When the capacitor voltage reaches the internal reference voltage of
1.284 V and VFLK is low, Q1 is turned off and Q2 is turned on. With Q2 on, VGHM is discharged by the resistor
connected to the RE pin. Once VGHM is discharged to five times VDD, Q2 is turned off and VGHM is high
impedance. In the application of not using this function, connect VDPM, VFLK with high.
VGH
VDPM
Q1
VGHM
1K
4R
Q3
R
Q2
S
RE
Q
R
INT_REG
IDLY
VDD
Vref
CE
SZ Q
RZ
Thermal shutdown
Q4
Power good from FBP
UVLO
VFLK
Figure 24. Gate Voltage Shaping Block TPS65162
VGH
VGHM
5 x VDD
Gate voltage shaping delay time
Charge CE capacitor to its threshold voltage
VFLK
Discharge CE capacitor
Figure 25. Gate Voltage Shaping Block TPS65162
22
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STEP-DOWN CONVERTER
The TPS65162 step down converter block is shown in Figure 26. The non-synchronous step down converter
operates at a fixed switching frequency using a fast response voltage mode topology with input voltage
feedforward. This topology allows simple internal compensation and it is designed to operate with ceramic output
capacitors. The converter drives an internal 2.8 A N-Channel MOSFET switch. The MOSFET driver is
referenced to the switch pin SWB. The N-Channel MOSFET requires a gate drive voltage higher than the switch
pin to turn the N-Channel MOSFET on. This is accomplished by a boost strap gate drive circuit running of the
step down converter switch pin. When the switch pin SWB is at ground the boot strap capacitor is charged to 8
V. This way the N-Channel Gate drive voltage is typically around 8 V.
Soft Start
To avoid high inrush current during startup, an internal soft-start is implemented. When the step down converter
is enabled over EN1, its reference voltage slowly rises from zero to its power good threshold of typically 90% of
Vref. When the reference voltage reaches this power good threshold, the Error amplifier is released to its normal
operation with its normal duty cycle. To further limit the inrush current during soft-start the converter frequency is
set to 1/4 of the switching frequency ƒs and 1/2 of ƒs by the comparator that monitors the feedback voltage.
refer to the internal block diagram. The typical soft-start is typically completed within 1ms.
Short Circuit Protection
To limit the short circuit current, the device has a cycle-by-cycle current limit. To prevent the short-circuit current
from rising above the internal current limit when the output is shorted to GND, the switching frequency is
reduced as well. This is implemented by two comparators monitoring the feedback voltage. The step-down
converter switching frequency is reduced to 1/2 of ƒfs when the feedback is below 0.9 V, and 1/4 of the
switching frequency when the feedback voltage is below 0.6 V.
PVIN
Regulator
8V
BOOT
Q3
PVIN
SWB
SWB
Control Logic
Current limit
Error Amplifier
FBB
Vref
Compensation
and
Softstart
Sawtooth
Generator
Clock/2
Logic
0.9V
Clock/4
0.6V
Clock
Clock
500/750 kHz
Clock select for short circuit
and softstart
Figure 26. Step Down Converter Block TPS65162
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Setting the Output Voltage
The step-down converter uses an external voltage divider to set the output voltage. The output voltage is
calculated as:
V out + 1.265 V
ǒ1 ) R5
Ǔ
R6
(9)
At load currents <1 mA, the device operates in discontinuous conduction mode. When the load current is
reduced to zero the output voltage rises slightly above the nominal output voltage. At zero load current, the
device skips clock cycles, but does not completely stop switching, thus the output voltage sits slightly above the
nominal output voltage. Therefore, the lower feedback resistor is selected to be around 1.2 kΩ to maintain
around 1 mA minimum load current.
Selecting the Feedforward Capacitor
The feedforward capacitor across the upper feedback resistor divider forms a zero around 135 kHz, and is
calculated as:
1
1
Cz +
+
+ 471.6 pF [ 470 pF
2 p 135kHz R5
2 p 135kHz 2.5kW
(10)
Usually the standard capacitor value closest to the calculated value is selected.
Inductor Selection
The TPS65162 step-down converter typically operates with a 10-µH inductor. For high efficiency, the inductor
should have a low DC resistance to minimize conduction loss. This must be considered when selecting the
appropriate inductor. In order to avoid inductor saturation, the inductor should be rated at least for the maximum
output current of the converter plus the inductor ripple current that will be calculated by:
1 * Vout
DI
Vin
DI L + Vout
I Lmax + I outmax ) L
2
L ƒ
(11)
where
ƒ = Switching Frequency (750 kHz, 500 kHz minimal)
L = Inductor Value (typically 10 µH)
∆IL= Peak to Peak inductor ripple current
ILmax = Maximum Inductor current
The highest inductor current occurs at maximum Vin. A more conservative approach is to select the inductor
current rating just for the typical switch-current limit of 3.5 A.
Table 5. Inductor Selection
INDUCTOR VALUE
24
COMPONENT SUPPLIER
DIMENSIONS in mm
Isat/DCR
10 µH
Coilcraft DO3316P-103
12.95 × 9.4 × 5.51
3.9 A/38 mΩ
10 µH
Sumida CDRH8D43-100
8.3 × 8.3 × 4.5
4.0 A/29 mΩ
10 µH
Wuerth Elektronik 744066100
10 × 10 × 3.8
4.0 A/25 mΩ
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Rectifier Diode Selection
To achieve high efficiency, a Schottky diode should be used. The reverse voltage rating should be higher than
the maximum output voltage of the step-down converter. The averaged rectified forward current for which the
Schottky diode should be rated is calculated as the off time of the step-down converter times the minimum
switch current of the TPS65162:
V
D = OUT
VIN
(12)
Iavg = (1 - D) × ISW = (1 -
VOUT
) × 2.8 A
VIN
(13)
where Isw = minimum switch current of the TPS65162 (2.8 A)
Usually a Schottky diode with 2 A maximum average rectified forward current rating is sufficient for most of the
applications. Secondly the Schottky rectifier has to be able to dissipate the power. The dissipated power is the
average rectified forward current times the diode forward voltage.
P D + I avg VF + Isw (1 * D) VF
with ISW = minimum switch current of the TPS65162 (2.8 A)
Table 6. Rectifier Diode Selection (Step-Down Converter)
CURRENT RATING Iavg
Vr
Vforward
RθJA
SIZE
COMPONENT SUPPLIER
3A
20 V
0.36 V at 3 A
46°C/W
SMC
MBRS320, International Rectifier
2A
20 V
0.44 V at 2 A
75°C/W
SMB
SL22, Vishay Semiconductor
2A
20 V
0.5 V at 2 A
75°C/W
SMB
SS22, Fairchild Semiconductor
Output Capacitor Selection
The device is designed to work with ceramic output capacitors. Two 22-µF output capacitors are sufficient for
most of the applications. Larger output capacitance improves the load transient response.
Table 7. Output Capacitor Selection Step-Down Converter
CAPACITOR
COMPONENT SUPPLIER
22 µF/6.3 V
Taiyo Yuden JMK212BJ226MG
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COMMENT
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OPERATIONAL AMPLIFIER 1 AND 2
The TPS65162 has two integrated operational amplifiers. The operational amplifiers can be used as a
gamma-correction buffer or as a VCOM buffer.
AVIN
POS2
OUT2
NEG2
POS1
2
OUT1
NEG1
1
3.3R
10nF
Proper termination when not in use
Series resistor for driving capacitive loads
Figure 27. Operational Amplifier Block TPS65162
The power supply pin for the opamps is the AVIN pin connected to the boost converter Vs. To achieve good
performance and minimize the output noise, a 1-µF bypass capacitor is required directly from the AVIN pin to
ground. The opamps are not designed to drive capacitive loads, therefore it is not recommended to connect a
capacitor directly to the output of the opamps. If capacitive loads are driven, use a series resistor at the output to
provide stable operation. With a 3.3-Ω series resistor, a capacitive load of 10 nF can be driven, which is usually
sufficient for typical LCD applications.
Operational Amplifier Termination
For some applications, not all of the amplifiers are used. To minimize device quiescent current the terminals
should be terminated. The negative terminal is connected to the output of the operational amplifier and positive
terminal is connected to GND and the output is left open. This termination minimizes device quiescent current
and maintains correct functionality of the device.
PCB LAYOUT DESIGN GUIDELINES
1. Place the power components outlined in bold first on the PCB.
2. Rout the traces outlined in bold with wide PCB traces.
3. Place a 1-µF bypass capacitor directly from the SUP pin to GND and from AVIN to GND.
26
Submit Documentation Feedback
TPS65162
www.ti.com
SLVS771 – MAY 2007
4.
5.
6.
7.
Use a short and wide trace to connect the SUP pin to the output of the boost converter Vs.
Place the 220-nF reference capacitor directly from REF to GND close to the IC pins.
The feedback resistor for the negative charge pump between FBN and REF should be >40 kΩ.
Use short traces for the charge-pump drive pin (DRVN) of VGL because the traces carry switching
waveforms.
8. Solder the PowerPad™ of the QFN package to GND, and use thermal vias to lower the thermal
resistance.
9. For more layout recommendations, refer to the TPS65162 evaluation module (EVM)
L1
10 mH
27
C11
1 mF
30
C12
22 nF
31
C13
22 nF
FB
SWI
VDD 3
VDPM
DRVN
SWB
FBB
R8
1.5 KΩ
C20
100 nF
24
L2
10 mH
21
D5
DLY1
AGND
POS1
NEG2
OUT2
POS2
DLY2
OUT1
C19
220 nF
47
R7
10 KΩ
R10
1 KΩ
FBN
REF
48
2
1
44
46
45
34
35
GND
VGH
25V/50mA
Vs
CBOOT 22
SWB 23
C17
470nF
R6
3.3kΩ
RE 7
PGND3
15
R5
62kΩ
VC
PGND2
R4
51 kW
C16
470 nF
VGHM 8
PGND1
17
D2D3
SS
C18
470 nF
16
41
VGH 9
10
FBP
NEG1
R3
200 kW
14
C10
22 mF
12
VIN
OGND
C7
470 nF
D4D5
C9
22 uF
DRVP
5 VFLK
VFLK
VGL
-5 V/50 mA
6
C8
22 mF
C7
220 pF
R2
3.6 kΩ
FREQ
28 CE
C14
100 pF
Enable Gate
Voltage shaping
R1
39 kΩ
13
32 EN2
28
Vs
15 V/1.5 A
C12
1 mF
39 42 43
AVIN
38
SW
37
SWO
EN1
26
SW
25
PVIN
C4
22 mF
33
C11
1 mF
C5
10 mF
C2
22 mF
PVIN
C1
22 mF
D1
SUP
Vin
8 V to 14 V
Vlogic
3.3 V/2.5 A
C21
R11
2.4 kΩ 470 pF
C22
22 mF
C23
22mF
18
29
11
C24
10nF
R12
1.5 kΩ
C25
22nF
36
Figure 28. PCB Layout Recommendation TPS65162
Submit Documentation Feedback
27
TPS65162
www.ti.com
SLVS771 – MAY 2007
TYPICAL APPLICATION
L1
10 mH
AVIN
C8
C9
22 mF 22 mF
C7
220 pF
D2D3
DRVP
S
VGH
C16
470 nF
C17
470 nF
R5
62 kW
FBP
SS
C12
22 nF
CE
C14
100 pF
Enable Gate
Voltage shaping
VDD
VDPM
SWB
Buck
Converter
C18
470 nF
FBB
FBN
R4
51 kW
R8
1.5 KW
C20
100 nF
SWB
S
D
DRVN
L2
10 mH
D5
Vlogic
3.3 V/2.5 A
C21
R11
2.4 kW 470 pF
REF
DLY1
AGND
PGND3
PGND2
PGND1
POS2
NEG2
C24
10 nF
DLY2
2
POS1
OUT1
NEG1
OGND
1
OUT2
C19
220 nF
VGH
25 V/50 mA
R7
10 KW
R10
1 KW
CBOOT
D4D5
R3
200 kW
Vs
RE
VFLK
VFLK
R6
3.3 kW
VGHM
Gate Voltage
Shaping
VC
C13
22 nF
28
R1
39 kW
Vs
15 V/1.5 A
C10
22 mF
R2
3.6 kW
D
VIN
C7
470 nF
SWI
SW
SW
FREQ
C12
1 mF
FB
Boost
Converter
EN2
VGL
-5V/50mA
SWO
EN1
PVIN
C4
22 mF
C11
1 mF
C11
1 mF
C5
10 mF
C2
22 mF
PVIN
C1
22 mF
D1
SUP
Vin
8 V to 14 V
GND
Submit Documentation Feedback
C25
22 nF
R12
1.5 kW
C22
22 mF
C23
22 mF
PACKAGE MATERIALS INFORMATION
www.ti.com
29-May-2007
TAPE AND REEL INFORMATION
Pack Materials-Page 1
PACKAGE MATERIALS INFORMATION
www.ti.com
Device
TPS65162RGZR
29-May-2007
Package Pins
RGZ
48
Site
Reel
Diameter
(mm)
Reel
Width
(mm)
A0 (mm)
B0 (mm)
K0 (mm)
P1
(mm)
FRB
330
16
7.3
7.3
1.5
12
TAPE AND REEL BOX INFORMATION
Device
Package
Pins
Site
Length (mm)
Width (mm)
Height (mm)
TPS65162RGZR
RGZ
48
FRB
342.9
336.6
28.58
Pack Materials-Page 2
W
Pin1
(mm) Quadrant
16
Q2
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