MAX1912：1.5x/2x High-Efficiency White LED Charge Pumps

The MAX1910/MAX1912 power LEDs with a regulated output voltage or current (up to 120mA) from an unregulated input supply (2.7V to 5.3V). These are complete DC-DC converters requiring only four small ceramic capacitors and no inductors. Input ripple is minimized by a unique regulation scheme that maintains a fixed 750kHz switching frequency over a wide load range. Also included are logic-level shutdown and soft-start to reduce input current surges at startup. The MAX1910 has two automatically selected operating modes: 1.5x and 2x. 1.5x mode improves efficiency at higher input voltages, while 2x mode maintains regulation at lower input voltages. The MAX1912 operates only in 1.5x mode. The MAX1910 and the MAX1912 are available in a space-saving 10-pin µMAX package.

Key Features

High-Efficiency 1.5x/2x Charge Pumps
Low Input Ripple with 750kHz Operation
200mV Current-Sense Threshold Reduces Power Loss
Current- or Voltage-Regulated Charge Pump
Up to 120mA Output Current
No Inductors Required
Small Ceramic Capacitors
Regulated ±5% LED Current
Load Disconnected in Shutdown
1µA Shutdown Current
Small 10-Pin µMAX Package

MAX1910, MAX1912: Typical Operating Circuit

Applications/Uses

Backup Battery Boost Converters
Cell Phones
Digital Still Cameras
MP3 Players
PDAs
White LED Backlighting

DataSheet

title	Download file
MAX1910-MAX1912 Data Sheet	MAX1910-MAX1912.pdf

Parametrics

Part Number	Battery Input	Regulation Topology	Max. No. of LEDs	LED Channels	LED Configuration	I_LED per Channel (A)	Dimming Control	P_OUT (W)	V_IN (V)	V_IN (V)	I_CC (mA)	LED String Volt. (V)	Oper. Freq. (kHz)	Package/Pins	Budgetary Price
Part Number	Battery Input	Regulation Topology	Max. No. of LEDs	LED Channels	LED Configuration	max	Dimming Control	P_OUT (W)	min	max	max	max	Oper. Freq. (kHz)	Package/Pins	See Notes
MAX1910	1-Cell Li+	Charge Pump	5	1	Parallel	0.12	Analog	0.5	2.7	5.3	2.5	5	750	µMAX/10	$1.10 @1k
MAX1912	1-Cell Li+	Charge Pump	4	1	Parallel	0.12	Analog	0.5	2.7	5.3	2.5	5	750	µMAX/10	$1.23 @1k

Design kits & evaluation modules

MAX1910EVKIT

Ordering Information

Part Number	Status	Recommended Replacement	Package	Temp	RoHS
MAX1912EUB	No Longer Available	MAX1912EUB+	µMAX,;10 pin;15.4 mm²	-40°C to +85°C	No
MAX1912EUB+	Active		µMAX,;10 pin;15.4 mm²	-40°C to +85°C	Lead Free
MAX1912EUB+T	Active		µMAX,;10 pin;15.4 mm²	-40°C to +85°C	Lead Free
MAX1912EUB-T	No Longer Available	MAX1912EUB+T	µMAX,;10 pin;15.4 mm²	-40°C to +85°C	No

MAX1910-MAX1912.pdf MAX1912

Driving LEDs in Battery-Operated Applications: Controlling Brightness Power Efficiently MAX8596

MAX1910-MAX1912.pdf MAX1912