High-Efficiency, 36V Step-Up Converters

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5

Typical Operating Characteristics (continued)

unless otherwise noted.)

Pin Description

PIN

NAME

FUNCTION

1

OUT

2IN

Input Voltage Supply. The input voltage range is 2.6V to 5.5V. Connect a 2.2µF ceramic capacitor

from IN to GND.

3

CTRL

Brightness Control Input. The voltage applied to CTRL controls LED brightness. Varying the voltage

from 0.24V to 1.65V (1.72V for the MAX8596X) adjusts the brightness from dim to 100% brightness,

respectively. Any voltage above 1.65V (1.72V) does not increase brightness. Hold CTRL below

100mV to shut down the IC after an 8.2ms delay.

4CS

Current-Sense Feedback Input. Connect a resistor from CS to GND to set the LED bias current. The

5

COMP

discharges to 0V through an internal 20k

Ω resistor in shutdown.

6

GND

Ground. Connect to PGND and the exposed pad directly under the IC.

7

PGND

Power Ground. Connect to GND and the exposed pad directly under the IC.

8LX

Inductor Connection. Connect LX to the node between the inductor and the Schottky diode. LX is

high impedance in shutdown.

—EP

Exposed Pad. Connect to a large ground plane for maximum package heat dissipation. Connect

directly to GND and PGND under the IC.

DIRECT-PWM DIMMING RESPONSE

MAX8595X toc08

10

µs/div

2V/div

32kHz 50%

DUTY CYCLE

0

0

0

0

500mV/div

AC-COUPLED

10mA/div

20mV/div

AC-COUPLED

CTRL STEP RESPONSE

MAX8595X toc07

20ms/div

1V/div

0

0

0

0

40mA/div

10V/div

100mA/div