900,000+ datasheet pdf search and download

Datasheet4U offers most rated semiconductors data sheet pdf




Maxim Integrated Semiconductor Electronic Components Datasheet

MAX8784 Datasheet

Switch Control and Operational Amplifier

No Preview Available !

19-0737; Rev 0; 1/07
EVAALVUAAILTAIOBNLEKIT
Step-Up Regulator, Internal Charge Pumps, Switch
Control, and Operational Amplifier for TFT LCDs
General Description
The MAX8784 generates supply rails for the thin-film
transistor (TFT) liquid-crystal display (LCD) panels in TVs
and monitors. It includes a step-up regulator, a regulated
positive and a negative charge-pump, three high-current
operational amplifiers, and Dual Mode™, logic-con-
trolled, high-voltage switch control block. HVS mode
automatically increases the output voltages of the boost
regulator and the positive charge-pump to stress test
display panels during production. The MAX8784 can
operate from input voltages of 4V to 5.5V and is opti-
mized for LCD TV panel and LCD monitor applications.
The step-up DC-DC regulator provides a regulated sup-
ply voltage for TFT source drivers. The step-up regulator
is a high-frequency (1.2MHz), high-efficiency, current-
mode regulator. The step-up regulator has a built-in
110m(typ) power MOSFET. The high-switching fre-
quency allows the use of ultra-small inductors and
ceramic capacitors. The current-mode architecture pro-
vides fast transient response and easy compensation.
The step-up regulator features output undervoltage pro-
tection, soft-start, internal current limit, and adjustable
output voltage by an external resistive divider.
The three operational amplifiers drive the LCD back-
plane and the gamma-correction-divider string. Each
operational amplifier has a fast slew rate (45V/µs), a
wide bandwidth (20MHz), and a high-output short-cir-
cuit current (200mA). Each op amp has rail-to-rail input
and rail-to-rail output operation.
The positive charge-pump regulator and the negative
charge-pump regulator provide regulated supply volt-
ages for the TFT gate drivers. The positive charge
pump is a two-stage charge pump, which requires no
external diodes. The output voltages of both charge
pumps are resistor adjustable. The logic-controlled
high-voltage switch allows the manipulation of the posi-
tive TFT gate-driver supply.
The MAX8784 is available in a small (5mm x 5mm), low-
profile (0.8mm), 40-pin TQFN package and operates
over the -40°C to +85°C temperature range.
Applications
LCD TVs and LCD Monitors
Ordering Information
PART
TEMP RANGE PIN-
PKG CODE
PACKAGE
MAX8784ETL+
-40°C to +85°C
40 TQFN
5mm x 5mm
T4055-1
+Denotes a lead(Pb)-free/RoHS-compliant package.
Dual Mode is a trademark of Maxim Integrated Products, Inc.
Features
o Step-Up Regulator Supply for LCD Panel Source
Driver
Fast Transient Response to Pulsed Load
Built-In 18V, 4A, 0.11n-Channel Power
MOSFET with Lossless Current Sensing
Cycle-by-Cycle Current-Limit Comparator
90% Efficiency (5V In to 15V Out)
1.2MHz Switching Frequency
o Three High-Current 19V Operational Amplifiers
180mA Output Short-Circuit Current
45V/µs Slew Rate
20MHz Bandwidth
Rail-to-Rail Input and Output Operation
o Regulated Charge-Pump Tripler with Integrated
Diodes for TFT Gate-On Supply
o Regulated Charge Pump for TFT Gate-Off Supply
o Built-In Sequencing
Internal Digital Soft-Start
36V Gate-On Switch
Startup Timing Capacitors for AVDD and GON
o Undervoltage and Thermal Protection
o 4V to 5.5V Input Operating Range
Simplified Operating Circuit
STEP-UP
VIN OUTPUT
STEP-UP
OUTPUT
TO
VCOM
TO
VCOM
TO
VCOM
VIN
VCC
POS1
NEG1
OUT1
POS2
NEG2
OUT2
POS3
OUT3
HVS
REF
AGND
MAX8784
FBN
VGOFF
DRVN
LX
PGND
FB
COMP
RSET
GDEL
ADEL
CTL
SHDN
GON
DRN
POUT
TCON
ON/OFF
PGND
SUP C1N
C1P C2N
FBP
C2P
STEP-UP
OUTPUT
VGON
STEP-UP
OUTPUT
________________________________________________________________ Maxim Integrated Products 1
For pricing, delivery, and ordering information, please contact Maxim Direct at 1-888-629-4642,
or visit Maxim’s website at www.maxim-ic.com.


Maxim Integrated Semiconductor Electronic Components Datasheet

MAX8784 Datasheet

Switch Control and Operational Amplifier

No Preview Available !

Step-Up Regulator, Internal Charge Pumps, Switch
Control, and Operational Amplifier for TFT LCDs
ABSOLUTE MAXIMUM RATINGS
VCC, CTL, HVS, SHDN, ADEL, GDEL to AGND ....-0.3V to +7.5V
REF, COMP, FB, FBN, FBP to AGND .........-0.3V to (VCC + 0.3V)
POS1, NEG1, POS2, NEG2, POS3, OUT1, OUT2,
OUT3 to AGND .......................................-0.3V to (VSUP + 0.3)
PGND, BGND to AGND.........................................-0.3V to +0.3V
LX, RSET to PGND .................................................-0.3V to +22V
SUP to AGND .........................................................-0.3V to +22V
DRVN to AGND.........................................-0.3V to (VSUP + 0.3V)
C1N, C2N to AGND ..................................-0.3V to (VSUP + 0.3V)
C1P to AGND .........................................................-0.3V to +30V
POUT to C2P, C1P to C2P......................................-0.3V to +22V
C2P, POUT to AGND..............................................-0.3V to +40V
DRN to GON............................................................-30V to +30V
REF Short Circuit to AGND.........................................Continuous
RMS VCC Current ................................................................50mA
RMS DRVN Current...........................................................400mA
LX, PGND RMS Current Rating.............................................2.4A
Continuous Power Dissipation (TA = +70°C)
40-Pin TQFN (derate 35.7mW/°C above +70°C) .......2857mW
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
Soldering Temperature (reflow) .......................................+260°C
GON, DRN to AGND ..............................................-0.3V to +40V
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
(VCC = +5V, Circuit of Figure 1, AVDD = SUP = +14V, TA = 0°C to +85°C. Typical values are at TA = +25°C, unless otherwise noted.)
PARAMETER
VCC Input Supply Range
VCC Undervoltage Lockout Threshold
VCC Quiescent Current
SHDN Input Low Voltage
SHDN Input High Voltage
SHDN Input Current
REFERENCE
REF Output Voltage
REF Load Regulation
REF Sink Current
REF Undervoltage Lockout Threshold
OSCILLATOR AND TIMING
Frequency
Oscillator Maximum Duty Cycle
Duration to Trigger Fault Condition
ADEL, GDEL Capacitor Charge Current
ADEL, GDEL Turn-On Threshold
STEP-UP REGULATOR
FB Regulation Voltage
FB Fault-Trip Level
FB Load Regulation
FB Line Regulation
FB Input Bias Current
CONDITIONS
VCC rising, typical hysteresis = 50mV
VFB = 1.3V, not switching
VFB = 1.1V, switching, no load, VSUP disconnected,
VFBP = VCC, VFBN = 0V
SHDN = GND
No external load
0 < ILOAD < 50µA
In regulation
Rising edge, typical hysteresis = 200mV
FB = COMP, CCOMP = 1nF
FB = COMP, CCOMP = 1nF, +25°C to +85°C
Falling edge
0 < ILOAD < full
VCC = 4.5V to 5.5V
VFB = 1.25V
MIN
4.0
2.4
1.8
-1
1.238
10
1000
87
47
4
1.235
1.238
0.96
TYP
2.6
1.0
4
1.250
1.0
1200
90
55
5
1.25
1.246
1.246
1.00
-1
0.25
100
MAX
5.5
2.8
6
0.05
0.8
+1
1.262
10
1.15
1400
93
65
6
1.32
1.256
1.256
1.04
200
UNITS
V
V
mA
V
V
µA
V
mV
µA
V
kHz
%
ms
µA
V
V
V
%
%/V
nA
2 _______________________________________________________________________________________


Part Number MAX8784
Description Switch Control and Operational Amplifier
Maker Maxim Integrated
Total Page 24 Pages
PDF Download

MAX8784 Datasheet PDF

View PDF for Mobile








Similar Datasheet

1 MAX878 Step-Up/Step-Down DC-DC Converters
Maxim
2 MAX8784 Switch Control and Operational Amplifier
Maxim Integrated
3 MAX878L (MAX877L - MAX879L) Step-Up & Down DC-DC Converters
Maxim Integrated Products





Part Number Start With

0    1    2    3    4    5    6    7    8    9    A    B    C    D    E    F    G    H    I    J    K    L    M    N    O    P    Q    R    S    T    U    V    W    X    Y    Z

Site map

Webmaste! click here

Contact us

Buy Components

Privacy Policy