MAX1518BETJ+-MAX1518BETJ+T Fast Delivery |IC PHOENIX CO.,LIMITED

MAX1518BETJ+ ,TFT-LCD DC-DC Converters with Operational AmplifiersApplicationsCOMPVCPAGND● Notebook Computer DisplaysMAX1518BDRVP● LCD Monitor PanelsGATE-ONVGONCONTR ..
MAX1518BETJ+T ,TFT-LCD DC-DC Converters with Operational AmplifiersFeaturesThe MAX1518B includes a high-performance step-up ● 2.6V to 6.5V Input Supply Rangeregulator ..
MAX1518ETJ ,TFT-LCD DC-DC Converters with Operational AmplifiersApplicationsCONTROLLERPGNDNotebook Computer DisplaysCOMPVCPAGNDLCD Monitor PanelsMAX1518DRVPAutomot ..
MAX1518ETJ+ ,TFT-LCD DC-DC Converters with Operational AmplifiersMAX1516/MAX1517/MAX151819-3244; Rev 0; 4/04TFT-LCD DC-DC Converters with Operational Amplifiers
MAX1518ETJ+T ,TFT-LCD DC-DC Converters with Operational AmplifiersFeaturesThe MAX1516/MAX1517/MAX1518 include a high-perfor-♦ 2.6V to 5.5V Input Supply Rangemance st ..
MAX1518ETJ+T ,TFT-LCD DC-DC Converters with Operational AmplifiersApplicationsCONTROLLERPGNDNotebook Computer DisplaysCOMPVCPAGNDLCD Monitor PanelsMAX1518DRVPAutomot ..
MAX4164ESD ,SOT23 / Micropower / Single-Supply / Rail-to-Rail I/O Op AmpsFeaturesThe MAX4162/MAX4163/MAX4164 are single/dual/quad,' 5-Pin SOT23 Package (MAX4162)micropower ..
MAX4165EUK ,High-Output-Drive, Precision, Low-Power, Single-Supply, Rail-to-Rail I/O Op Amps with ShutdownFeaturesThe MAX4165–MAX4169 family of operational amplifiers ♦ 80mA (min) Output Drive Capability c ..
MAX4165EUK-T ,High-Output-Drive / Precision / Low-Power / Single- Supply / Rail-to-Rail I/O Op Amps with ShutdownApplicationsOrdering Information continued at end of data sheet.Portable Head-Phone Speaker Drivers ..
MAX4166ELA+T ,High-Output-Drive, Precision, Low-Power, Single-Supply, Rail-to-Rail I/O Op Amps with ShutdownELECTRICAL CHARACTERISTICS (continued) (V = +2.7V to +6.5V, V = 0V, V = 0V, V = (V / 2), R = 100kΩ ..
MAX4166EPA ,High-Output-Drive / Precision / Low-Power / Single- Supply / Rail-to-Rail I/O Op Amps with ShutdownMAX4165–MAX416919-1224; Rev 1; 10/97High-Output-Drive, Precision, Low-Power, Single-Supply, Rail-to ..
MAX4166EPA+ ,High-Output-Drive, Precision, Low-Power, Single-Supply, Rail-to-Rail I/O Op Amps with ShutdownApplicationsOrdering Information continued on last page.Portable/Battery-Powered Audio

MAX1518BETJ+-MAX1518BETJ+T
TFT-LCD DC-DC Converter with Operational Amplifiers
General Description
The MAX1518B includes a high-performance step-up
regulator, two linear-regulator controllers, and high-current
operational amplifiers for active-matrix, thin-film transistor
(TFT), liquid-crystal displays (LCDs). Also included is a
logic-controlled, high-voltage switch with adjustable delay.
The step-up DC-DC converter provides the regulated
supply voltage for the panel source driver ICs. The
converter is a high-frequency (1.2MHz) current-mode
regulator with an integrated 14V n-channel MOSFET
that allows the use of ultra-small inductors and ceramic
capacitors. It provides fast transient response to pulsed
loads while achieving efficiencies over 85%.
The gate-on and gate-off linear-regulator controllers
provide regulated TFT gate-on and gate-off supplies using
external charge pumps attached to the switching node. The
MAX1518B includes five high-performance operational
amplifiers. These amplifiers are designed to drive the LCD
backplane (VCOM) and/or the gamma-correction divider
string. The device features high output current (±150mA), fast slew rate (13V/μs), wide bandwidth (12MHz), and
rail-to-rail inputs and outputs.
The MAX1518B is available in a 32-pin thin QFN package
with a maximum thickness of 0.8mm for ultra-thin LCD
panels.
Applications●Notebook Computer Displays●LCD Monitor Panels
Features●2.6V to 6.5V Input Supply Range●1.2MHz Current-Mode Step-Up Regulator Fast Transient Response to Pulsed Load High-Accuracy Output Voltage (1.5%) • Built-In 14V, 2.4A, 0.16Ω n-Channel MOSFET High Efficiency (90%)●Linear-Regulator Controllers for VGON and VGOFF●High-Performance Operational Amplifiers ±150mA Output Short-Circuit Current • 13V/μs Slew Rate 12MHz, -3dB Bandwidth Rail-to-Rail Inputs/Outputs●Logic-Controlled, High-Voltage Switch with
Adjustable Delay●Timer-Delay Fault Latch for All Regulator Outputs●Thermal-Overload Protection●0.6mA Quiescent Current
Pin Configuration appears at end of data sheet.
PARTTEMP RANGEPIN-PACKAGE
MAX1518BETJ-40°C to +100°C32 Thin QFN
(5mm x 5mm)
STEP-UP
CONTROLLER
GATE-ON
CONTROLLER
SWITCH
CONTROL
GATE-OFF
CONTROLLER
REF
VCNVCP
VMAIN
PGND
AGND
DRVP
FBP
VCP
VGON
VCN
VGOFF
DEL
CTL
DRVN
FBN
NEG4
REF
POS4
NEG5
POS5
OUT4
OUT5
BGND
NEG2
POS2
OP3
POS3
OUT2
OUT3
POS1
OUT1
NEG1
SUP
COM
DRN
SRC
COMP
VIN
MAX1518B
OP2
OP1
OP5
OP4
MAX1518BTFT-LCD DC-DC Converter with
Operational Amplifiers
Minimal Operating Circuit
Ordering Information
EVALUATION KIT AVAILABLE
IN, CTL to AGND......................................................-0.3V to +7V
COMP, FB, FBP, FBN, DEL, REF to AGND....-0.3V to (VIN + 0.3V)
PGND, BGND to AGND......................................................±0.3V
LX to PGND............................................................-0.3V to +14V
SUP to AGND.........................................................-0.3V to +14V
DRVP, SRC to AGND..............................................-0.3V to +30V
POS_, NEG_, OUT_ to AGND.................-0.3V to (VSUP + 0.3V)
DRVN to AGND...................................(VIN - 30V) to (VIN + 0.3V)
DRN to AGND..........................................-0.3V to (VSRC + 0.3V)
DRN to COM............................................................-30V to +30V
OUT_ Maximum Continuous Output Current....................±75mA
LX Switch Maximum Continuous RMS Output Current.........1.6A
Continuous Power Dissipation (TA = +70°C)
32-Pin Thin QFN (derate 21.2mW/°C above+70°C)...1702mW
Operating Temperature Range ..........................-40°C to +100°C
Junction Temperature.......................................................+150°C
Storage Temperature Range..............................-65°C to +150°C
Lead Temperature (soldering, 10s)...................................+300°C
(VIN = 3V, VSUP = 8V, PGND = AGND = BGND = 0, IREF = 25μA, TA = 0°C to +85°C. Typical values are at TA = +25°C, unless
otherwise noted.)
PARAMETERSYMBOLCONDITIONSMINTYPMAXUNITS
IN Supply RangeVIN2.66.5V
IN Undervoltage-Lockout
ThresholdVUVLOVIN rising, typical hysteresis = 200mV2.252.52.70V
IN Quiescent CurrentIIN
VFB = VFBP = 1.4V, VFBN = 0,
LX not switching0.60.8
VFB = 1.1V, VFBP = 1.4V, VFBN = 0,
LX switching611
Duration to Trigger Fault
Condition200ms
REF Output Voltage-2µA < IREF < 50µA, VIN = 2.6V to 5.5V1.2311.2501.269V
Thermal ShutdownTemperature rising+160°CHysteresis15
MAIN STEP-UP REGULATOR
Output Voltage RangeVMAINVIN13V
Operating FrequencyfOSC102012001380kHz
Oscillator Maximum Duty Cycle848790%
FB Regulation VoltageVFBNo load
TA = +25°C to +85°C1.2211.2331.245TA = 0°C to +85°C1.2181.2331.247
FB Fault Trip LevelVFB falling1.121.161.19V
FB Load Regulation0 < IMAIN < full load, transient only-1.6%
FB Line RegulationVIN = 2.6V to 5.5V+0.04±0.15%/ V
FB Input Bias CurrentVFB = 1.4V-40+40nA
FB Transconductance∆ICOMP = 5µA75160280µS
FB Voltage GainFB to COMP600V/ V
MAX1518BTFT-LCD DC-DC Converter withOperational Ampliiers
Absolute Maximum Ratings
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 in the operational sections of the specifications is not implied. Exposure to absolute maximum rating conditions for extended periods may affect
device reliability.
Electrical Characteristics
(VIN = 3V, VSUP = 8V, PGND = AGND = BGND = 0, IREF = 25μA, TA = 0°C to +85°C. Typical values are at TA = +25°C, unless
otherwise noted.)
PARAMETERSYMBOLCONDITIONSMINTYPMAXUNITS
LX On-ResistanceRLX(ON)160250mΩ
LX Leakage CurrentILXVLX = 13V0.0240µA
LX Current LimitILIMVFB = 1V, duty cycle = 65%2.53.03.5A
Current-Sense
Transconductance3.03.85.0S
Soft-Start PeriodtSS14ms
Soft-Start Step SizeILIM/8A
OPERATIONAL AMPLIFIERS
SUP Supply RangeVSUP4.513.0V
SUP Supply CurrentISUPBuffer coniguration, VPOS_ = 4V, no load2.43.8mA
Input Offset VoltageVOS(VNEG_, VPOS_, VOUT_) @ VSUP/2,
TA = +25°C012mV
Input Bias CurrentIBIAS(VNEG_ , VPOS_, VOUT_) @ VSUP/2+1±50nA
Input Common-Mode RangeVCM0VSUPV
Common-Mode Rejection RatioCMRR0 ≤ (VNEG_, VPOS_) ≤ VSUP45dB
Open-Loop Gain125dB
Output Voltage Swing, HighVOH
IOUT_ = 100µAVSUP -
VSUP -
IOUT_ = 5mAVSUP -
VSUP -
Output Voltage Swing, LowVOLIOUT_ = -100µA215mV
IOUT_ = -5mA80150
Short-Circuit CurrentTo VSUP/2, source or sink50150mA
Output Source and Sink Current(VNEG_ , VPOS_, VOUT_) @ VSUP/2,|∆VOS| < 10mV (|∆VOS| < 30mV for OUT3)40mA
Power-Supply Rejection RatioPSRRDC, 6V ≤ VSUP ≤ 13V,
(VNEG_, VPOS_) @ VSUP/260dB
Slew Rate13V/µs
-3dB BandwidthRL = 10kΩ, CL = 10pF, buffer coniguration12MHz
Gain-Bandwidth ProductGBWBuffer coniguration8MHz
GATE-ON LINEAR-REGULATOR CONTROLLER
FBP Regulation VoltageVFBPIDRVP = 100µA1.2311.2501.269V
FBP Fault Trip LevelVFBP falling0.961.001.04V
FBP Input Bias CurrentIFBPVFBP = 1.4V-50+50nA
FBP Effective Load-Regulation
Error (Transconductance)VDRVP = 10V, IDRVP = 50µA to 1mA-0.7-1.5%
FBP Line (IN) Regulation ErrorIDRVP = 100µA, 2.6V < VIN < 5.5V±1.5±5mV
MAX1518BTFT-LCD DC-DC Converter withOperational Ampliiers
Electrical Characteristics (continued)
(VIN = 3V, VSUP = 8V, PGND = AGND = BGND = 0, IREF = 25μA, TA = 0°C to +85°C. Typical values are at TA = +25°C, unless
otherwise noted.)
PARAMETERSYMBOLCONDITIONSMINTYPMAXUNITS
DRVP Sink CurrentIDRVPVFBP = 1.1V, VDRVP = 10V15mA
DRVP Off-Leakage CurrentVFBP = 1.4V, VDRVP = 28V0.0110µA
Soft-Start PeriodtSS14ms
Soft-Start Step SizeVREF/
128V
GATE-OFF LINEAR-REGULATOR CONTROLLER
FBN Regulation VoltageVFBNIDRVN = 100µA235250265mV
FBN Fault Trip LevelVFBN rising370420470mV
FBN Input Bias CurrentIFBNVFBN = 0-50+50nA
FBN Effective Load-Regulation
Error (Transconductance)VDRVN = -10V, IDRVN = 50µA to 1mA1125mV
FBN Line (IN) Regulation ErrorIDRVN = 0.1mA, 2.6V < VIN < 5.5V±0.7±5mV
DRVN Source CurrentIDRVNVFBN = 500mV, VDRVN = -10V14mA
DRVN Off-Leakage CurrentVFBN = 0V, VDRVN = -25V-0.01-10µA
Soft-Start PeriodtSS14ms
Soft-Start Step SizeVREF/
128V
POSITIVE GATE-DRIVER TIMING AND CONTROL SWITCHES
DEL Capacitor Charge CurrentDuring startup, VDEL = 1V456µA
DEL Turn-On ThresholdVTH(DEL)1.191.251.31V
DEL Discharge Switch
On- ResistanceDuring UVLO, VIN = 2.2V20Ω
CTL Input Low VoltageVIN = 2.6V to 5.5V0.6V
CTL Input High VoltageVIN = 2.6V to 5.5V2V
CTL Input Leakage CurrentCTL = AGND or IN-1+1µA
CTL-to-SRC Propagation Delay100ns
SRC Input Voltage Range28V
SRC Input CurrentISRCVDEL = 1.5V, CTL = IN50100µAVDEL = 1.5V, CTL = AGND1530
SRC to COM Switch On-
ResistanceRSRC(ON)VDEL = 1.5V, CTL = IN612Ω
DRN to COM Switch On-
ResistanceRDRN(ON)VDEL = 1.5V, CTL = AGND3570Ω
MAX1518BTFT-LCD DC-DC Converter withOperational Ampliiers
Electrical Characteristics (continued)
(VIN = 3V, VSUP = 8V, PGND = AGND = BGND = 0, IREF = 25μA, TA = 0°C to +85°C. Typical values are at TA = +25°C, unless
otherwise noted.)
PARAMETERSYMBOLCONDITIONSMINTYPMAXUNITS
IN Supply RangeVIN2.65.5V
IN Undervoltage-Lockout
ThresholdVUVLOVIN rising, typical hysteresis = 150mV2.2502.715V
IN Quiescent CurrentIIN
VFB = VFBP = 1.4V, VFBN = 0,
LX not switching0.8mA
VFB = 1.1V, VFBP = 1.4V, VFBN = 0,
LX switching11
REF Output Voltage-2µA < IREF < 50µA, VIN = 2.6V to 5.5V1.2221.269V
MAIN STEP-UP REGULATOR
Output Voltage RangeVMAINVIN13V
Operating FrequencyfOSC10201380kHz
FB Regulation VoltageVFBNo load1.2121.250V
FB Line RegulationVIN = 2.6V to 5.5V±0.15%/ V
FB Input Bias CurrentVFB = 1.4V-40+40nA
FB Transconductance∆ICOMP = 5µA75300µS
LX On-ResistanceRLX(ON)250mΩ
LX Current LimitILIMVFB = 1V, duty cycle = 65%2.53.5A
OPERATIONAL AMPLIFIERS
SUP Supply RangeVSUP4.513.0V
SUP Supply CurrentISUPBuffer coniguration, VPOS_ = 4V, no load3.8mA
Input Offset VoltageVOS(VNEG_, VPOS_, VOUT_) @ VSUP/212mV
Input Common-Mode RangeVCM0VSUPV
Output Voltage Swing, HighVOH
IOUT_ = 100µAVSUP
-15mV
IOUT_ = 5mAVSUP
Output Voltage Swing, LowVOL
IOUT_ = -100µA15IOUT_ = -5mA150
Short-Circuit CurrentTo VSUP/2Source50mASink50
Output Source-and-Sink Current(VNEG_ , VPOS_, VOUT_) @ VSUP/2, |∆VOS| < 10mV (|VOS| < 30mV for OUT3)40mA
GATE-ON LINEAR-REGULATOR CONTROLLER
FBP Regulation VoltageVFBPIDRVP = 100µA1.2181.269V
FBP Effective Load-Regulation
Error (Transconductance)VDRVP = 10V, IDRVP = 50µA to 1mA-2%
FBP Line (IN) Regulation ErrorIDRVP = 100µA, 2.6V < VIN < 5.5V5mV
MAX1518BTFT-LCD DC-DC Converter withOperational Ampliiers
Electrical Characteristics (continued)
(VIN = 3V, VSUP = 8V, PGND = AGND = BGND = 0, IREF = 25μA, TA = 0°C to +85°C. Typical values are at TA = +25°C, unless
otherwise noted.)
Note 1: Specifications to -40°C are guaranteed by design, not production tested.
PARAMETERSYMBOLCONDITIONSMINTYPMAXUNITS
GATE-OFF LINEAR-REGULATOR CONTROLLER
FBN Regulation VoltageVFBNIDRVN = 100µA235265mV
FBN Effective Load-Regulation
Error (Transconductance)VDRVN = -10V, IDRVN = 50µA to 1mA25mV
FBN Line (IN) Regulation ErrorIDRVN = 0.1mA, 2.6V < VIN < 5.5V5mV
DRVN Source CurrentIDRVNVFBN = 500mV, VDRVN = -10V1mA
POSITIVE GATE-DRIVER TIMING AND CONTROL SWITCHES
DEL Capacitor Charge CurrentDuring startup, VDEL = 1V46µA
DEL Turn-On ThresholdVTH(DEL)1.191.31V
CTL Input Low VoltageVIN = 2.6V to 5.5V0.6V
CTL Input High VoltageVIN = 2.6V to 5.5V2V
SRC Input Voltage Range28V
SRC Input CurrentISRCVDEL = 1.5V, CTL = IN100µAVDEL = 1.5V, CTL = AGND30
SRC-to-COM Switch
On- ResistanceRSRC(ON)VDEL = 1.5V, CTL = IN12Ω
DRN-to-COM Switch
On- ResistanceRDRN(ON)VDEL = 1.5V, CTL = AGND70Ω
MAX1518BTFT-LCD DC-DC Converter withOperational Ampliiers
Electrical Characteristics (continued)
(Circuit of Figure 1. VIN = 5V, VMAIN = 13V, VGON = 24V, VGOFF = -8V, VOUT1 = VOUT2 = VOUT3 = VOUT4 = VOUT5 = 6.5V, TA = +25°C
unless otherwise noted.)
SWITCHING FREQUENCY
vs. INPUT VOLTAGE
MAX1518B toc02
INPUT VOLTAGE (V)
SWITCHING FREQUENCY (MHz)
STEP-UP SUPPLY CURRENT
vs. SUPPLY VOLTAGE
MAX1518B toc03
SUPPLY VOLTAGE (V)
SUPPLY CURRENT (mA)
NO LOAD, SUP DISCONNECTED,
R1 = 95.3kΩ, R2 = 10.2kΩ
CURRENT INTO INDUCTOR
CURRENT INTO IN PIN
STEP-UP REGULATOR SOFT-START
(HEAVY LOAD)
MAX1518B toc04
2ms/div
A: VIN, 5V/div
B: VMAIN, 5V/div
C: INDUCTOR CURRENT, 1A/div
10ms/div
STEP-UP REGULATOR PULSED
LOAD-TRANSIENT RESPONSE
13V
200mA
MAX1518B toc05
A: LOAD CURRENT, 1A/div
B: VMAIN, 200mV/div, AC-COUPLED
C: INDUCTOR CURRENT, 1A/div
TIMER DELAYED OVERLOAD PROTECTION
MAX1518B toc06
220ms
STEP-UP EFFICIENCY
vs. LOAD CURRENT
MAX1518B toc01
LOAD CURRENT (mA)
EFFICIENCY (%)
VIN = 5.0V
VOUT = 13V
VIN = 3.3V
REF VOLTAGE LOAD REGULATION
MAX1518B toc07
REF VOLTAGE (V)302010
MAX1518BTFT-LCD DC-DC Converter withOperational Ampliiers
Typical Operating Characteristics
(Circuit of Figure 1. VIN = 5V, VMAIN = 13V, VGON = 24V, VGOFF = -8V, VOUT1 = VOUT2 = VOUT3 = VOUT4 = VOUT5 = 6.5V, TA = +25°C
unless otherwise noted.)
GATE-ON REGULATOR LINE REGULATION
MAX1518B toc08
INPUT VOLTAGE (V)
OUTPUT VOLTAGE ERROR (%)2827262524
VGON = 23.5V
IGON = 20mA
GATE-ON REGULATOR LOAD REGULATION
MAX1518B toc09
LOAD CURRENT (mA)
VOLTAGE ERROR (%)105
GATE-OFF REGULATOR LINE REGULATION
MAX1518B toc10
INPUT VOLTAGE (V)
OUTPUT VOLTAGE ERROR (%)
VGOFF = -8V
IGOFF = 50mA
GATE-OFF REGULATOR LOAD REGULATION
MAX1518B toc11
LOAD CURRENT (mA)
VOLTAGE ERROR (%)302010
-1.0504ms/div
POWER-UP SEQUENCE
MAX1518B toc12
A: VMAIN, 10V/div
B: VSRC, 20V/div
C: VGOFF, 10V/div
D: VGON, 20V/div
SUP SUPPLY CURRENT
vs. SUP VOLTAGE
ISUP
(mA)
MAX1518B toc13
VPOS = VSUP/2
BUFFER CONFIGURATON
40µs/div
OPERATIONAL-AMPLIFIER
RAIL-TO-RAIL INPUT/OUTPUT
MAX1518B toc14
A: INPUT SIGNAL, 2V/div
VSUP = 6V
MAX1518BTFT-LCD DC-DC Converter withOperational Ampliiers
Typical Operating Characteristics (continued)
(Circuit of Figure 1. VIN = 5V, VMAIN = 13V, VGON = 24V, VGOFF = -8V, VOUT1 = VOUT2 = VOUT3 = VOUT4 = VOUT5 = 6.5V, TA = +25°C
unless otherwise noted.)
PINNAMEFUNCTIONSRCSwitch Input. Source of the internal high-voltage p-channel MOSFET. Bypass SRC to PGND with a
minimum 0.1µF capacitor close to the pins.REFReference Bypass Terminal. Bypass REF to AGND with a minimum of 0.22µF close to the pins. AGNDAnalog Ground for Step-Up Regulator and Linear Regulators. Connect to power ground (PGND)
underneath the IC.PGND
Power Ground. PGND is the source of the main step-up n-channel power MOSFET. Connect PGND
to the output-capacitor ground terminals through a short, wide PCB trace. Connect to analog ground
(AGND) underneath the IC.OUT1Operational-Ampliier 1 OutputNEG1Operational-Ampliier 1 Inverting InputPOS1Operational-Ampliier 1 Noninverting InputOUT2Operational-Ampliier 2 OutputNEG2Operational-Ampliier 2 Inverting InputPOS2Operational-Ampliier 2 Noninverting InputBGNDAnalog Ground for Operational Ampliiers. Connect to power ground (PGND) underneath the IC.POS3Operational-Ampliier 3 Noninverting InputOUT3Operational-Ampliier 3 OutputSUPOperational-Ampliier Power Input. Positive supply rail for the operational ampliiers. Typically
connected to VMAIN. Bypass SUP to BGND with a 0.1µF capacitor. POS4Operational-Ampliier 4 Noninverting InputNEG4Operational-Ampliier 4 Inverting Input
400ns/div
OPERATIONAL-AMPLIFIER
LOAD-TRANSIENT RESPONSE
MAX1518B toc15
-50mA
A: OUTPUT VOLTAGE, 1V/div, AC-COUPLED
B: OUTPUT CURRENT, 50mA/div
+50mA
1µs/div
OPERATIONAL-AMPLIFIER
LARGE-SIGNAL STEP RESPONSE
MAX1518B toc16
A: INPUT SIGNAL, 2V/div
B: OUTPUT SIGNAL, 2V/div
VSUP = 6V
400ns/div
OPERATIONAL-AMPLIFIER
SMALL-SIGNAL STEP RESPONSE
MAX1518B toc17
A: INPUT SIGNAL, 100mV/div
B: OUTPUT SIGNAL, 100mV/div
MAX1518BTFT-LCD DC-DC Converter withOperational Ampliiers
Pin Description
Typical Operating Characteristics (continued)
PINNAMEFUNCTIONOUT4Operational-Ampliier 4 OutputPOS5Operational-Ampliier 5 Noninverting InputNEG5Operational-Ampliier 5 Inverting InputOUT5Operational-Ampliier 5 OutputLXn-Channel Power MOSFET Drain and Switching Node. Connect the inductor and Schottky diode to LX
and minimize the trace area for lowest EMI.INSupply Voltage Input. IN can range from 2.6V to 6.5V.FBStep-Up Regulator Feedback Input. Regulates to 1.236V (nominal). Connect a resistive voltage-divider
from the output (VMAIN) to FB to analog ground (AGND). Place the divider within 5mm of FB.COMPStep-Up Regulator Error-Ampliier Compensation Point. Connect a series RC from COMP to AGND.
See the Loop Compensation section for component selection guidelines.FBP
Gate-On Linear-Regulator Feedback Input. FBP regulates to 1.25V (nominal). Connect FBP to the
center of a resistive voltage-divider between the regulator output and AGND to set the gate-on linear-
regulator output voltage. Place the resistive voltage-divider close to the pin.DRVPGate-On Linear-Regulator Base Drive. Open drain of an internal n-channel MOSFET. Connect DRVP to
the base of an external pnp pass transistor. See the Pass-Transistor Selection section.FBN
Gate-Off Linear-Regulator Feedback Input. FBN regulates to 250mV (nominal). Connect FBN to the
center of a resistive voltage-divider between the regulator output and REF to set the gate-off linear-
regulator output voltage. Place the resistive voltage-divider close to the pin. DRVNGate-Off Linear-Regulator Base Drive. Open drain of an internal p-channel MOSFET. Connect DRVN to
the base of an external npn pass transistor. See the Pass-Transistor Selection section.DELHigh-Voltage Switch Delay Input. Connect a capacitor from DEL to AGND to set the high-voltage switch
startup delay.CTL
High-Voltage Switch Control Input. When CTL is high, the high-voltage switch between COM and SRC
is on and the high-voltage switch between COM and DRN is off. When CTL is low, the high-voltage
switch between COM and SRC is off and the high-voltage switch between COM and DRN is on. CTL is
inhibited by the undervoltage lockout and when the voltage on DEL is less than 1.25V.DRNSwitch Input. Drain of the internal high-voltage back-to-back p-channel MOSFETs connected to COM.COMInternal High-Voltage MOSFET Switch Common Terminal. Do not allow the voltage on COM to exceed
VSRC.
MAX1518BTFT-LCD DC-DC Converter withOperational Ampliiers
Pin Description (continued)
Typical Operating Circuit
The MAX1518B Typical Operating Circuit (Figure 1) is a
complete power-supply system for TFT LCDs. The circuit
generates a +13V source-driver supply and +24V and -8V
gate-driver supplies. The input voltage range for the IC is
from +2.6V to +6.5V. The listed load currents in Figure 1
are available from a +4.5V to +5.5V supply. Table 1 lists
some recommended components, and Table 2 lists the
contact information of component suppliers.
Detailed Description
The MAX1518B contains a high-performance step-
up switching regulator, two low-cost linear-regulator
controllers, multiple high-current operational amplifiers,
and startup timing and level-shifting functionality useful for
active-matrix TFT LCDs. Figure 2 shows the MAX1518B
Functional Diagram.
Main Step-Up Regulator
The main step-up regulator employs a current-mode,
fixed-frequency PWM architecture to maximize loop band-
width and provide fast transient response to pulsed loads
typical of TFT-LCD panel source drivers. The 1.2MHz
switching frequency allows the use of low-profile inductors
and ceramic capacitors to minimize the thickness of LCD
panel designs. The integrated high-efficiency MOSFET
and the IC’s built-in digital soft-start functions reduce the
number of external components required while controlling
inrush currents. The output voltage can be set from VIN to
13V with an external resistive voltage-divider. To generate
an output voltage greater than 13V, an external cascoded
MOSFET is needed. See the Generating Output Voltages
> 13V section in the Design Procedures.
The regulator controls the output voltage and the power
delivered to the output by modulating the duty cycle (D) of
the internal power MOSFET in each switching cycle. The
duty cycle of the MOSFET is approximated by:
MAININ
MAINDV−≈
Figure 3 shows the Functional Diagram of the step-up
regulator. An error amplifier compares the signal at FB
to 1.236V and changes the COMP output. The voltage at
COMP sets the peak inductor current. As the load varies,
the error amplifier sources or sinks current to the COMP
output accordingly to produce the inductor peak current
necessary to service the load. To maintain stability at high
duty cycles, a slope-compensation signal is summed with
the current-sense signal.
On the rising edge of the internal clock, the controller
sets a flip-flop, turning on the n-channel MOSFET and
applying the input voltage across the inductor. The current
through the inductor ramps up linearly, storing energy in
its magnetic field. Once the sum of the current-feedback
signal and the slope compensation exceeds the COMP
voltage, the controller resets the flip-flop and turns off
the MOSFET. Since the inductor current is continuous,
a transverse potential develops across the inductor that
turns on the diode (D1). The voltage across the inductor
then becomes the difference between the output voltage
and the input voltage.
Table 1. Component List
Table 2. Component Suppliers
DESIGNATIONDESCRIPTION22µF, 6.3V X5R ceramic capacitor (1210)
TDK C3225X5R0J227M22µF, 16V X5R ceramic capacitor (1812)
TDK C4532X5X1C226M3A, 30V Schottky diode (M-lat)
Toshiba CMS02
D2, D3200mA, 100V, dual ultra-fast diodes (SOT23)
Fairchild MMBD4148SE3.0µH, 3A inductor
Sumida CDRH6D28-3R0200mA, 40V pnp bipolar transistor (SOT23)
Fairchild MMBT3906200mA, 40V npn bipolar transistor (SOT23)
Fairchild MMBT3904
SUPPLIERPHONEFAXWEBSITE
Fairchild408-822-2000408-822-2102www.fairchildsemi.com
Sumida847-545-6700847-545-6720www.sumida.com
TDK847-803-6100847-390-4405www.component.tdk.com
Toshiba949-455-2000949-859-3963www.toshiba.com/taec
MAX1518BTFT-LCD DC-DC Converter withOperational Ampliiers
Figure 1. Typical Operating Circuit
0.1µF
0.1µF
0.1µF
3.0µH
22µF
VMAIN
13V/500mA
95.3kΩ
10.2kΩ
6.8kΩ
192kΩ
10.0kΩ
0.47µF
VGON
24V/20mA
0.1µF
VIN
4.5V TO 5.5V
22µF
220µF
C18
0.1µF
R10
10Ω
180kΩ
6.8kΩ
0.1µF
332kΩ
40.2kΩ
0.22µF
0.22µF
VGOFF
-8V/50mA
0.033µF
TO VCOM
BACKPLANE
COMP
DRVN
FBN
REF
AGND
PGND
DRVP
FBP
SRC
COM
DEL
NEG1
NEG2
OUT2
OUT3
NEG4
OUT4
NEG5
OUT5
OUT1
DRN
CTL
SUP
BGND
POS1
POS2
POS3
POS4
POS5
MAX1518B
MAX1518BTFT-LCD DC-DC Converter withOperational Ampliiers
STEP-UP
CONTROLLER
GATE-ON
CONTROLLER
SWITCH
CONTROL
GATE-OFF
CONTROLLER
REF
VCNVCP
VMAIN
PGND
AGND
DRVP
FBP
VCP
VGON
VCN
VGOFF
DEL
CTL
DRVN
FBN
NEG4
REF
POS4
NEG5
POS5
OUT4
OUT5
BGND
NEG2
POS2
OP3
POS3
OUT2
OUT3
POS1
OUT1
NEG1
SUP
COM
DRN
SRC
COMP
VIN
MAX1518B
OP2
OP1
OP5
OP4
MAX1518BTFT-LCD DC-DC Converter withOperational Ampliiers

Partno	Mfg	Dc	Qty	Available	Descript
MAX1518BETJ+	MAXIM	N/a	5800	avai	TFT-LCD DC-DC Converters with Operational Amplifiers
MAX1518BETJ+T \|MAX1518BETJT	MAXIM	N/a	4132	avai	TFT-LCD DC-DC Converters with Operational Amplifiers