MAX8595X-MAX8596X Datasheet, PDF (1/8 Pages) Maxim Integrated Products – High-Efficiency, 36V Step-Up Converters with TA Derating Option for 2 to 9 White LEDs

19-3485; Rev 0; 11/04
EVAALVUAAILTAIOBNLEKIT
High-Efficiency, 36V Step-Up Converters
with T_A Derating Option for 2 to 9 White LEDs
General Description
The MAX8595X/MAX8596X drive up to nine white LEDs
with constant current and high efficiency to provide
LCD backlighting in cell phones, PDAs, and other
handheld devices. The series connection allows the
LED currents to be identical for uniform brightness and
minimizes the number of traces to the LEDs. The
MAX8595X regulates constant LED current over the
entire temperature range. The MAX8596X features an
ambient-temperature derating function to avoid over-
driving the white LEDs during high ambient tempera-
tures, enabling higher drive current below +42°C.
A single Dual Mode™ input provides a simple means of
brightness adjustment and on/off control. Fast 1MHz
current-mode PWM operation allows for small input and
output capacitors and a small inductor while minimizing
ripple on the input supply/battery. Soft-start eliminates
inrush current during startup.
The MAX8595X/MAX8596X are available in a space-
saving, 8-pin, 3mm x 3mm TDFN package.
Applications
Cell Phones and Smart Phones
PDAs, Palmtops, and Wireless Handhelds
e-Books and Subnotebooks
White LED Display Backlighting
Dual Mode is a trademark of Maxim Integrated Products, Inc.
Typical Operating Circuit
INPUT
2.6V TO 5.5V
2.2µF
OUTPUT
UP TO 38V
ANALOG OR
PWM DIMMING
200Hz TO 200kHz
IN
LX
OUT
MAX8595X
CTRL ^MAX8596X PGND
COMP
GND
CS
0.1µF
2 TO 9 LEDs
Features
♦ Up to Nine LEDs at 25mA
♦ Temperature Derating Function to Allow Fewer
LEDs for Same Light (MAX8596X)
♦ 86% Efficiency (P_LEDs / P_IN)
♦ 1.7% Current-Regulation Accuracy
♦ Output Overvoltage Protection
♦ Flexible Dimming Control
Analog
Direct-PWM Internal Filter
♦ 1MHz PWM Switching Frequency
♦ 0.1µF Output Capacitor
♦ 12mV_P-P Low Input Ripple
♦ Soft-Start Eliminates Inrush Current
♦ 2.6V to 5.5V Input Range
♦ 0.3µA Shutdown Current
♦ Pin Compatible with the MAX1561 and MAX1599
♦ TDFN 3mm x 3mm x 0.8mm Package with
Exposed Paddle
Ordering Information
PART
TEMP RANGE PIN-PACKAGE
PKG
CODE
MAX8595XETA -40°C to +85°C 8 TDFN 3mm x 3mm T833-1
MAX8596XETA* -40°C to +85°C 8 TDFN 3mm x 3mm T833-1
*Future product—contact factory for availability.
Pin Configuration
TOP VIEW
8 7 65
MAX8595X
MAX8596X
1 2 34
TDFN
3mm x 3mm x 0.8mm
________________________________________________________________ Maxim Integrated Products 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.