MAX1582EBE+T ,High-Efficiency / 26V Step-Up Converter for White LED Main and Subdisplay BacklightingELECTRICAL CHARACTERISTICS(V = +3.0V, V = 20V, L1 = 22µH, C = 0.1µF, C = 0.022µF, R = 7.5Ω , V = +1 ..
MAX1582EBE-T ,High-Efficiency / 26V Step-Up Converter for White LED Main and Subdisplay BacklightingApplications Ordering InformationCell Phones with One or Two DisplaysTOPPART TEMP RANGE PIN-PACKAGE ..
MAx1582ETC ,High-Efficiency / 26V Step-Up Converter for White LED Main and Subdisplay BacklightingFeaturesThe MAX1582 drives up to six white LEDs in series with Accurate Current Regulation for Un ..
MAX1582ETC+ ,High-Efficiency Step-Up Converters for White LED Main and Subdisplay BacklightingELECTRICAL CHARACTERISTICS(V = +3.0V, V = 20V, L1 = 22µH, C = 0.1µF, C = 0.022µF, R = 7.5Ω, V = +1. ..
MAX1582ETC+T ,High-Efficiency Step-Up Converters for White LED Main and Subdisplay BacklightingFeatures♦ Accurate Current Regulation for UniformThe MAX1582/MAX1582Y drive up to six white LEDs in ..
MAX1582ETC-T ,High-Efficiency Step-Up Converters for White LED Main and Subdisplay BacklightingApplicationsM AX1582E BE + T -40°C to +85°C 16 UCSP-16 1582EBECell Phones with One or Two Displays ..
MAX4243ESD ,Single/Dual/Quad / !.8V/10A / SOT23 / Beyond-the-Rails Op AmpsMAX4240–MAX424419-1343; Rev 0; 3/98Single/Dual/Quad, +1.8V/10µA, SOT23, Beyond-the-Rails Op Amps___ ..
MAX4243EUB ,Single/Dual/Quad / !.8V/10A / SOT23 / Beyond-the-Rails Op AmpsELECTRICAL CHARACTERISTICS — T = +25°CA(V = +1.8V to +5.5V, V = 0, V = 0, V = V / 2, R = 100kΩ tied ..
MAX4244ESD ,Single/Dual/Quad / !.8V/10A / SOT23 / Beyond-the-Rails Op AmpsMAX4240–MAX424419-1343; Rev 0; 3/98Single/Dual/Quad, +1.8V/10µA, SOT23, Beyond-the-Rails Op Amps___ ..
MAX4244ESD+ ,Single/Dual/Quad, +1.8V/10µA, SOT23, Beyond-the-Rails Op AmpsMAX4240–MAX424419-1343; Rev 3; 9/06Single/Dual/Quad, +1.8V/10µA, SOT23,Beyond-the-Rails Op Amps
MAX4245AXT ,Ultra-Small, Rail-to-Rail I/O with Disable, Single/Dual-Supply, Low-Power Op AmpsElectrical Characteristics(V = +2.7V, V = 0V, V = 0V, V = V /2, R connected from OUT to V /2, SHDN_ ..
MAX4245AXT-T ,Ultra-Small / Rail-to-Rail I/O with Disable / Single-/Dual-Supply / Low-Power Op AmpsApplicationsOrdering InformationPortable CommunicationsPIN- TOPSingle-Supply Zero-Crossing Detector ..
MAX1582EBE+T-MAX1582EBE-T-MAx1582ETC
High-Efficiency / 26V Step-Up Converter for White LED Main and Subdisplay Backlighting
General DescriptionThe MAX1582 drives up to six white LEDs in series with
a constant current to provide display backlighting for
two (main and sub-) displays in cell phones and other
hand-held devices. This configuration eliminates the
need for ballast resistors and expensive factory calibra-
tion. The proprietary dual-output, step-up pulse-width
modulation (PWM) converter includes a 30V, low RDSON
N-channel MOSFET switch for high efficiency and maxi-
mum battery life.
The MAX1582 utilizes 1MHz current-mode PWM control
to allow small input and output capacitors and a small
inductor, while minimizing ripple on the input supply and
avoiding interference to sensitive circuitry in the equip-
ment. Integrated overvoltage protection eliminates the
need for an external zener diode to protect the IC from
open circuit. Flexible dimming control utilizes either an
analog control signal or direct digital PWM control with-
out external RC filtering. This also increases dimming
accuracy at low brightness levels. The PWM dimming
signal can be any frequency from 200Hz to 200kHz.
Soft-start eliminates inrush current during startup.
The MAX1582 is available in tiny 4 ✕4 chip-scale
(UCSP™) and 12-pin thin QFN packages.
ApplicationsCell Phones with One or Two Displays
Smart Phones, Palmtops, and Wireless
Handhelds
Other Hand-Held Devices with Dual Displays
FeaturesAccurate Current Regulation for Uniform
IlluminationLights Up Two LED Sections for Main and
SubdisplaysUp to 84% EfficiencyInternal High-Power, 30V MOSFETLow 15mVP-PInput RippleFlexible Dimming Control
Analog DAC Controlled
Direct-Digital PWM (No RC Required)
from 200Hz to 200kHzOvervoltage Protection to Eliminate Zener DiodeConstant 1MHz PWM OperationLow-Profile Inductor and CapacitorsSoft-Start Eliminates Inrush Current2.6V to 5.5V Input0.01µA (typ) Shutdown CurrentTiny UCSP (2.1mm ✕2.1mm ✕0.61mm) and Thin
QFN (4mm ✕4mm) Packages
MAX1582, 26V Step-Up Converter
for White LED Main and Subdisplay Backlighting
Ordering Information
Pin Configurations
Typical Application Circuit
MAX1582
High-Efficiency, 26V Step-Up Converter
for White LED Main and Subdisplay Backlighting
ABSOLUTE MAXIMUM RATINGS
ELECTRICAL CHARACTERISTICS(VV+= +3.0V, VOUT1 = 20V, L1 = 22µH, COUT = 0.1µF, CCOMP = 0.022µF, RSENSE = 7.5Ω, VCTRL = +1.5V, EN1 = EN2 = V+, TA =
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.
V+, VP, CTRL to GND............................................-0.3V to +6.0V
PGND to GND.......................................................-0.3V to +0.3V
LX, OUT1 to GND...................................................-0.3V to +30V
OUT2 to GND.........................................................-0.3V to +14V
COMP, CS, EN1, EN2 to GND....................-0.3V to (VV++ 0.3V)
ILX....................................................................................................1ARMS
Continuous Power Dissipation (TA = +70°C)
12-Pin Thin QFN (derate 16.9mW/°C above +70°C)....1349mW
16-Pin UCSP (derate 6.5mW/°C above +70°C)..............518mW
Operating Temperature Range...........................-40°C to +85°C
Junction Temperature......................................................+150°C
Storage Temperature Range.............................-65°C to +150°C
Lead Temperature (soldering, 10s).................................+300°C
MAX1582
High-Efficiency, 26V Step-Up Converter
for White LED Main and Subdisplay Backlighting
ELECTRICAL CHARACTERISTICS (continued)(VV+= +3.0V, VOUT1 = 20V, L1 = 22µH, COUT = 0.1µF, CCOMP = 0.022µF, RSENSE = 7.5Ω, VCTRL = +1.5V, EN1 = EN2 = V+, TA =
ELECTRICAL CHARACTERISTICS (VV+= +3.0V, VOUT1 = +20V, L1 = 22µH, COUT = 0.1µF, CCOMP = 0.022µF, RSENSE = 7.5Ω, VCTRL = +1.5V, EN1 = EN2 = V+, TA =
Typical Operating Characteristics(See the Typical Applications Circuit, VV+= VVP= 3.6V, ILED= 15mA, L1 = 22µH, COUT1= 0.1µF, CCOMP= 0.022µF, RSENSE= 7.5Ω,
VCTRL= 1.5V, 4 LEDs, TA= +25°C, unless otherwise noted.)
MAX1582
High-Efficiency, 26V Step-Up Converter
for White LED Main and Subdisplay Backlighting
ELECTRICAL CHARACTERISTICS (continued)(VV+= +3.0V, VOUT1 = +20V, L1 = 22µH, COUT = 0.1µF, CCOMP = 0.022µF, RSENSE = 7.5Ω, VCTRL = +1.5V, EN1 = EN2 = V+, TA =
-40°C to +85°C, unless otherwise noted.) (Notes 1, 3)guaranteed by design and characterization but are not production tested.
Note 2:The minimum output voltage is the input voltage minus the forward voltage drop of the Schottky diode:
VOUT(MIN)= VV+- VDIODE
Note 3:Specifications to -40°C are guaranteed by design and not production tested.
MAX1582
High-Efficiency, 26V Step-Up Converter
for White LED Main and Subdisplay Backlighting
Typical Operating Characteristics (continued)(See the Typical Applications Circuit, VV+= VVP= 3.6V, ILED= 15mA, L1 = 22µH, COUT1= 0.1µF, CCOMP= 0.022µF, RSENSE= 7.5Ω,
VCTRL= 1.5V, 4 LEDs, TA= +25°C, unless otherwise noted.)
MAX1582
Detailed DescriptionThe MAX1582’s high efficiency and small size make it
ideally suited to drive up to six series-connected LEDs.
Separate enable inputs are provided to control the main
and subdisplay backlighting. The MAX1582 operates as
a boost DC-to-DC converter that regulates output current
rather than voltage. It provides even illumination by sourc-
ing the same output current through each LED, eliminat-
ing the need for expensive factory calibration. The fast
1MHz internal oscillator allows for a small inductor and
small input and output capacitors while minimizing input
and output ripple.
Shutdown for Main and SubdisplayThe MAX1582 has two enable inputs (EN1 and EN2)
used to enable or shutdown the main and subdisplay
LEDs. When EN1 and EN2 are both high, all LEDs are
lit. With EN1 high and EN2 low, the main-display LEDs
are lit, and the subdisplay LEDs are shorted by the
MAX1582. With EN1 low and EN2 high, the main-display
LEDs are shorted and the subdisplay LEDs are lit.
When both EN1 and EN2 are low, the MAX1582 enters
shutdown, reducing supply current to 0.01µA (typ).
Although the internal N-channel MOSFET does not
switch in shutdown, there is still a DC-current path
High-Efficiency, 26V Step-Up Converter
for White LED Main and Subdisplay BacklightingFigure 1. Functional Diagram
