Document
www.DataSheet4U.com
19-0825; Rev 0; 5/07
KIT ATION EVALU E L B A AVAIL
125mA 1x/1.5x Charge Pumps for 5 White LEDs in 3mm x 3mm TDFN
General Description Features
♦ 93% Max/85% Avg. Efficiency (PLED/PBATT) Over Li+ Battery Discharge ♦ 1% LED Current Accuracy ♦ 125mA Total Drive Capability ♦ Adaptive 1x/1.5x Mode Switchover ♦ Single-Wire, Serial-Pulse Dimming (MAX8630X) Independent On/Off/Dimming for Main and Sub Linear—Full, 31/32nd, 30/32nd, … 1/32nd ♦ Direct-PWM Dimming (MAX8630W) ♦ 15, 18, 20, and 25mA Full-Scale Versions ♦ Low 0.1µA Shutdown Current ♦ Soft-Start Eliminates Inrush Current ♦ Output Overvoltage Protection ♦ Thermal-Derating Function Protects LEDs ♦ 14-Pin, 3mm x 3mm TDFN Package
MAX8630W/MAX8630X
The MAX8630W/MAX8630X charge pumps drive up to 5 white LEDs with regulated constant current up to 125mA total. By utilizing adaptive 1x/1.5x charge-pump modes and very low-dropout current regulators, they achieve high efficiency over the full 1-cell Li+ battery input voltage range. The 1MHz fixed-frequency switching allows for tiny external components, and the regulation scheme is optimized to ensure low EMI and low input ripple. An integrated derating function protects the LEDs from overheating during high ambient temperatures. The MAX8630W/MAX8630X are factory trimmed for fullscale LED current options of 15mA, 18mA, 20mA, and 25mA. The MAX8630X uses two enable inputs (ENM for 3 main LEDs and ENS for 2 sub LEDs) for simple on/off control and single-wire, serial-pulse dimming in 32 linear steps. The MAX8630W uses a single direct PWM input (PWM) to control all 5 LEDs with DC current proportional to the PWM duty cycle. If both ENM and ENS (or PWM) are kept low for more than 4ms, the MAX8630_ enters shutdown. The MAX8630W/MAX8630X are available in a 14-pin, 3mm x 3mm TDFN package (0.8mm max height).
Ordering Information
PART MAX8630WETD15+T PINPACKAGE 14 TDFN-14 (3mm x 3mm) TOP MARK ADQ PKG CODE T1433-2
Applications
Display Backlight (Up to 5 LEDs) Main (3 LEDs) + Sub (2 LEDs) Displays Cell Phones and Smartphones PDAs, Digital Cameras, and Camcorders
Note: All devices are specified to operate over the -40°C to +85°C operating temperature range. +Denotes a lead-free package. T = Tape and reel. Ordering Information continued at end of data sheet. Selector Guide appears at end of data sheet.
Typical Operating Circuit
1μF INPUT 2.7V TO 5.5V 1μF GND MAX8630X LED1 LED2 ENM LED3 SUB LED4 ENABLE SUB ON/OFF AND DIMMING ENS C2P C2N LED5 1 GND 2 C1N 3 IN
Pin Configuration
ENS (PWM) 8 7 OUT
TOP VIEW
LED1 LED2 LED3 LED4 LED5 10 5 C2P
C1P IN
C1N
OUT
OUTPUT 1μF MAIN
14
13
12
11
ENABLE MAIN ON/OFF AND DIMMING
MAX8630W MAX8630X
4 C2N
1μF
( ) ARE FOR MAX8630W
TDFN 3mm × 3mm
________________________________________________________________ Maxim Integrated Products
C1P
ENM (CPWM) 9 6
1
For pricing, delivery, and ordering information, please contact Maxim/Dallas Direct! at 1-888-629-4642, or visit Maxim’s website at www.maxim-ic.com.
www.DataSheet4U.com
125mA 1x/1.5x Charge Pumps for 5 White LEDs in 3mm x 3mm TDFN MAX8630W/MAX8630X
ABSOLUTE MAXIMUM RATINGS
IN, OUT to GND.....................................................-0.3V to +6.0V C1N, C2N, ENM, CPWM, ENS, PWM to GND ............................................-0.3V to (VIN + 0.3V) LED_ to GND ............................................-0.3V to (VOUT + 0.3V) C1P, C2P to GND ...-0.3V to greater of (VOUT + 1V) or (VIN + 1V) OUT Short Circuit to GND ..........................................Continuous Continuous Power Dissipation (TA = +70°C) 14-Pin TDFN 3mm x 3mm (derate 18.2mW/°C above +70°C) .............................1454mW Junction Temperature ......................................................+150°C Storage Temperature Range .............................-65°C to +150°C Lead Temperature (soldering, 10s) .................................+300°C
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 = 3.6V, VGND = 0V, EN_ (PWM) = IN, TA = -40°C to +85°C, unless otherwise noted. Typical values are at TA = +25°C.) (Note 1)
PARAMETER IN Operating Voltage Undervoltage-Lockout Threshold Undervoltage-Lockout Hysteresis Output Overvoltage Protection Threshold No-Load Supply Current Shutdown Supply Current Soft-Start Time (tSOFT-START) MAX8630_ETD15 Full-Scale LED Current MAX8630_ETD18 MAX8630_ETD20 MAX8630_ETD25 Full-Scale LED Current Accuracy Derating Function Start Temperature Derating Function Slope LED_ Dropout Voltage 1x to 1.5x Mode Transition Threshold Input Voltage Mode Transition Hysteresis 1.5x Mode Regulation Voltage OUT Pulldown Resistance in Shutdown Minimum.