MAX8727ETB Fast Delivery |IC PHOENIX CO.,LIMITED

MAX8727ETB ,TFT-LCD Step-Up DC-DC ConverterApplicationsOrdering InformationNotebook Computer DisplaysPART TEMP RANGE PIN-PACKAGELCD Monitor Pa ..
MAX8727ETB+ ,TFT-LCD Step-Up DC-DC ConverterApplicationsPART TEMP RANGE PIN-PACKAGEMAX8727ETB -40°C to +85°C 10 Thin DFN 3mm x 3mmNotebook Comp ..
MAX8727ETB+T ,TFT-LCD Step-Up DC-DC ConverterFeaturesThe MAX8727 is a high-performance step-up DC-DC♦ 90% Efficiencyconverter that provides a re ..
MAX8728ETJ+ ,Low-Cost Multiple-Output Power Supply for LCD Monitors/TVsApplicationsLCD Monitors LCD TVsAVV DDINOrdering InformationVLINL GATELX2VLPIN- PACKAGEGND2PART TEM ..
MAX8728ETJ+T ,Low-Cost Multiple-Output Power Supply for LCD Monitors/TVsELECTRICAL CHARACTERISTICS(Circuit of Figure 1, V = V = V = 12V, V = +3.3V, V = 28V, GND1 = GND2 = ..
MAX872CPA ,10A / Low-Dropout / Precision Voltage Referencesapplications.' Load Regulation Over Temp.0.6mV/mA Max (MAX872)1.0mV/mA Max (MAX874)' ±500µA Sink/So ..
MB84VD21183EM-70PBS , Stacked MCP (Multi-Chip Package) FLASH MEMORY & SRAM CMOS
MB84VD21194EM-70PBS , Stacked MCP (Multi-Chip Package) FLASH MEMORY & SRAM CMOS
MB84VD22181FM-70PBS , 32M (X16) FLASH MEMORY & 4M (X16) STATIC RAM
MB84VD22182EE-90 ,32M (x 8/x16) FLASH MEMORY & 4M (x 8/x16) STATIC RAMFUJITSU SEMICONDUCTORDS05-50204-2EDATA SHEETStacked MCP (Multi-Chip Package) FLASH MEMORY & SRAMCMO ..
MB84VD22183EE-90 ,32M (x 8/x16) FLASH MEMORY & 4M (x 8/x16) STATIC RAMFEATURES• Power supply voltage of 2.7 to 3.3 V• High performance90 ns maximum access time (Flash)85 ..
MB84VD22184FM-70 , 32M (X16) FLASH MEMORY & 4M (X16) STATIC RAM

MAX8727ETB
TFT-LCD Step-Up DC-DC Converter
General Description
The MAX8727 is a high-performance step-up DC-DC
converter that provides a regulated supply voltage for
active-matrix thin-film transistor (TFT) liquid-crystal dis-
plays (LCDs). The MAX8727 incorporates current-
mode, fixed-frequency, pulse-width modulation (PWM)
circuitry with a built-in n-channel power MOSFET to
achieve high efficiency and fast transient response.
Users can select 640kHz or 1.2MHz operation using a
logic input pin (FREQ). The high switching frequencies
allow the use of ultra-small inductors and low-ESR
ceramic capacitors. The current-mode architecture pro-
vides fast transient response to pulsed loads. A com-
pensation pin (COMP) gives users flexibility in adjusting
loop dynamics. The 30V internal MOSFET can generate
output voltages up to 24V from an input voltage
between 2.6V and 5.5V. Soft-start slowly ramps the input
current and is programmed with an external capacitor.
The MAX8727 is available in a 10-pin thin DFN package.
Applications
Notebook Computer Displays
LCD Monitor Panels
Features90% EfficiencyAdjustable Output from VINto 24V2.6V to 5.5V Input Supply RangeInput Supply Undervoltage LockoutPin-Programmable 640kHz/1.2MHz Switching
FrequencyProgrammable Soft-Start0.1µA Shutdown CurrentSmall 10-Pin Thin DFN Package
MAX8727
TFT-LCD Step-Up DC-DC Converter
Ordering Information
Pin Configuration
Minimal Operating Circuit
MAX8727
TFT-LCD Step-Up DC-DC Converter
ABSOLUTE MAXIMUM RATINGS
ELECTRICAL CHARACTERISTICS
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.
LX to GND..............................................................-0.3V to +26V
IN, SHDN, FREQ, FB to GND...................................-0.3V to +6V
COMP, SS to GND.........................................-0.3V to VIN+ 0.3V
LX Switch Maximum Continuous RMS Current.....................2.4A
Continuous Power Dissipation (TA= +70°C)
10-Pin Thin DFN (derate 24.4mW/°C above +70°C)....1951mW
Operating Temperature Range...........................-40°C to +85°C
Junction Temperature......................................................+150°C
Storage Temperature Range.............................-65°C to +160°C
Lead Temperature (soldering, 10s).................................+300°C
MAX8727
TFT-LCD Step-Up DC-DC Converter
ELECTRICAL CHARACTERISTICS (continued)
(VIN= VSHDN= 3V, FREQ = GND, TA= 0°C to +85°C. Typical values are at TA= +25°C, unless otherwise noted.) (Note 1)
ELECTRICAL CHARACTERISTICS
MAX8727
TFT-LCD Step-Up DC-DC Converter
Note 1:Specifications to -40°C are guaranteed by design, not production tested.
ELECTRICAL CHARACTERISTICS (continued)
(VIN= VSHDN= 3V, FREQ = GND, TA= -40°C to +85°C, unless otherwise noted.) (Note 1)
EFFICIENCY vs. LOAD CURRENT
(1.2MHz OPERATION)
MAX8727 toc01
LOAD CURRENT (mA)
EFFICIENCY (%)
EFFICIENCY vs. LOAD CURRENT
(640kHz OPERATION)
MAX8727 toc02
LOAD CURRENT (mA)
EFFICIENCY (%)
LOAD REGULATION
MAX8727 toc03
LOAD CURRENT (mA)
LOAD REGULATION (%)
SUPPLY CURRENT
vs. SUPPLY VOLTAGE
MAX8727 toc05
SUPPLY VOLTAGE (V)
SUPPLY CURRENT (mA)
SUPPLY CURRENT vs. TEMPERATURE
(SWITCHING)
MAX8727 toc06
TEMPERATURE (°C)
SUPPLY CURRENT (mA)6040200-20
Typical Operating Characteristics
(Circuit of Figure1. VIN= 5V, VMAIN= 15V, TA= +25°C unless otherwise noted.)
MAX8727
TFT-LCD Step-Up DC-DC Converter
SOFT-START
(RLOAD = 30Ω)
MAX8727 toc07
1ms/div
INDUCTOR
CURRENT
1A/div
VOUT
5V/div
LOAD-TRANSIENT RESPONSE
(ILOAD = 50mA TO 550mA)
MAX8727 toc08
1µs/div
INDUCTOR
CURRENT
1A/div
50mA
15V
VOUT
5mV/div
AC-COUPLED
IOUT
500mA/div
PULSED LOAD-TRANSIENT RESPONSE
(ILOAD = 100mA TO 1.1A)
MAX8727 toc09
1µs/div
INDUCTOR
CURRENT
1A/div
0.1A
15V
VOUT
5mV/div
AC-COUPLED
IOUT
1A/div
SWITCHING WAVEFORMS
(ILOAD = 600mA)
MAX8727 toc10
1µs/div
INDUCTOR
CURRENT
1A/div
10V/div
Typical Operating Characteristics (continued)
(Circuit of Figure1. VIN= 5V, VMAIN= 15V, TA= +25°C unless otherwise noted.)
MAX8727
TFT-LCD Step-Up DC-DC Converter
Figure 1 Typical Operating Circuit
Detailed Description
The MAX8727 is a highly efficient power supply that
employs a current-mode, fixed-frequency, pulse-width
modulation (PWM) architecture for fast transient
response and low-noise operation. The device regu-
lates the output voltage through a combination of an
error amplifier, two comparators, and several signal
generators (Figure 2). The error amplifier compares the
signal at FB to 1.24V and varies the COMP output. The
voltage at COMP determines the current trip point each
time the internal MOSFET turns on. As the load
changes, the error amplifier sources or sinks current to
the COMP output to command the inductor peak cur-
rent necessary to service the load. To maintain stability
at high duty cycles, a slope-compensation signal is
summed with the current-sense signal.
At light loads, this architecture allows the MAX8727 to
“skip” cycles to prevent overcharging the output voltage.
In this region of operation, the inductor ramps up to a
peak value of approximately 50mA, discharges to the
output, and waits until another pulse is needed again.
Output Current Capability
The output current capability of the MAX8727 is a func-
tion of current limit, input voltage, operating frequency,
and inductor value. Because of the slope compensa-
tion used to stabilize the feedback loop, the inductor
current limit depends on the duty cycle. The current
limit is determined by the following equation:
ILIM= (1.26 - 0.35 x D) x ILIM_EC
where ILIM_ECis the current limit specified at 75% duty
cycle (see the Electrical Characteristics) and D is the
duty cycle.
The output current capability depends on the current-
limit value and is governed by the following equation:
where ILIMis the current limit calculated above, ηis the
regulator efficiency (85% nominal), and D is the duty
cycle. The duty cycle when operating at the current
limit is:
where VDIODEis the rectifier diode forward voltage and
RONis the on-resistance of the internal MOSFET.
MAX8727
TFT-LCD Step-Up DC-DC Converter
Figure 2. MAX8727 Functional Diagram

Partno	Mfg	Dc	Qty	Available	Descript
MAX8727ETB	MAXIM	N/a	1875	avai	TFT-LCD Step-Up DC-DC Converter