Rainbow Electronics MAX8596Z - Manual

General Description
The MAX8595Z/MAX8596Z drive up to 8 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
MAX8595Z regulates constant LED current over the
entire temperature range. The MAX8596Z 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 MAX8595Z/MAX8596Z 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
Features
♦ Up to 8 LEDs at 25mA
♦ Temperature Derating Function to Allow Fewer
LEDs for Same Light (MAX8596Z)
♦
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
MAX8595Z/MAX8596Z
High-Efficiency, 32V Step-Up Converters
with T A Derating Option for 2 to 8 White LEDs
________________________________________________________________ Maxim Integrated Products 1
GND COMP
CS
1 2
LX PGND
IN
CTRL
OUT
TOP VIEW
3 4
MAX8595Z
MAX8596Z
8 7 6 5
TDFN
3mm x 3mm x 0.8mm
Pin Configuration
Ordering Information
MAX8595Z
MAX8596Z
IN LX
OUT
PGND
CS
CTRL
COMP
GND
0.1 µF
2 TO 8 LEDs
200Hz TO 200kHz
ANALOG OR
PWM DIMMING
2.2 µF
INPUT
2.6V TO 5.5V
OUTPUT
UP TO 34V
Typical Operating Circuit
19-3558; Rev 0; 8/04
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.
EVALUATION KIT
AVAILABLE
PART
TEMP
RANGE
PIN-PACKAGE
PKG
CODE
MAX8595Z ETA -40 °C to +85°C 8 TDFN 3mm x 3mm T833-1
MAX8596Z ETA -40 °C to +85°C 8 TDFN 3mm x 3mm T833-1
Dual Mode is a trademark of Maxim Integrated Products, Inc.