ZXLD1362
1A LED driver with internal switch
Description
The ZXLD1362 is a continuous mode
inductive step-down converter, designed for
driving single or multiple series connected
LEDs efficiently from a voltage source higher
than the LED voltage. The device operates
from an input supply between 6V and 60V and
provides an externally adjustable output
current of up to 1A. Depending upon supply
voltage and external components, this can
provide up to 48 watts of output power.
The ZXLD1362 includes the output switch and
a high-side output current sensing circuit,
which uses an external resistor to set the
nominal average output current.
Output current can be adjusted above, or
below the set value, by applying an external
control signal to the 'ADJ' pin.
The ADJ pin will accept either a DC voltage or a
PWM waveform. Depending upon the control
frequency, this will provide either a continuous
(dimmed) or a gated output current. Soft-start
can be forced using an external capacitor from
the ADJ pin to ground.
Applying a voltage of 0.2V or lower to the ADJ
pin turns the output off and switches the device
into a low current standby state.
Features
Applications
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Simple low parts count
Internal 60V NDMOS switch
Up to 1A output current
Single pin on/off and brightness control
using DC voltage or PWM
PWM resolution up to 1000:1
Soft start capability
High efficiency (up to 95%)
Wide input voltage range: 6V to 60V
65V transient capability
Low power shutdown
Up to 500kHz switching frequency
Inherent open-circuit LED protection
Typical 2% output current accuracy
Pin connections
LX 1
Low voltage halogen replacement LEDs
Automotive lighting
Low voltage industrial lighting
LED back-up lighting
Illuminated signs
Emergency lighting
SELV lighting
LCD TV backlighting
Refrigeration lights
Typical application circuit
5
Rs
VIN (24V)
VIN
0.1⍀
GND 2
L1 68H
4 ISENSE
ADJ 3
C1
D1
4.7F
TSOT23-5
Top view
VIN
100nF
ISENSE
ADJ
ZXLD1362
LX
GND
GND
Issue 1 - December 2007
© Zetex Semiconductors plc 2007
1
www.zetex.com
