ZXLD1322DCCTC Diodes Zetex, ZXLD1322DCCTC Datasheet

IC LED DRIVR WHITE BCKLGT 14-DFN

ZXLD1322DCCTC

Manufacturer Part Number
ZXLD1322DCCTC
Description
IC LED DRIVR WHITE BCKLGT 14-DFN
Manufacturer
Diodes Zetex
Type
Backlight, White LEDr
Datasheet

Specifications of ZXLD1322DCCTC

Topology
PWM, Step-Down (Buck), Step-Up (Boost)
Number Of Outputs
1
Internal Driver
Yes
Type - Primary
General Purpose
Type - Secondary
White LED
Frequency
600kHz
Voltage - Supply
2.5 V ~ 15 V
Mounting Type
Surface Mount
Package / Case
14-DFN
Operating Temperature
-40°C ~ 125°C
Current - Output / Channel
700mA
Internal Switch(s)
Yes
Efficiency
80%
Lead Free Status / RoHS Status
Lead free / RoHS Compliant
Voltage - Output
-
Other names
ZXLD1322DCCTR
ZXLD1322
Document number: DS32166 Rev. 3 - 2
Description
Notes:
The ZXLD1322 is an inductive DC-DC converter, with an internal switch, designed for driving single or multiple LEDs in
series up to a total of 700mA output current. Applications cover input voltages ranging from 2.5V to 15V. Depending upon
supply voltage and external components, this can provide up to 12W of output power. The device employs a variable 'on'
and 'off' time control scheme with adjustable peak switch current limiting and operates in Buck/Boost mode, offering higher
power efficiency and lower system cost than conventional PFM buck/boost circuitry. The device includes the DC-DC
converter, a high-side current monitor and an NPN switching transistor to provide an integrated solution offering small PCB
size, competitive cost/performance, high power efficiency of DC-DC conversion and maximum LED brightness/reliability.
More importantly, it retains design flexibility to add customer specific features. The feedback control circuitry inside the
ZXLD1322 provides excellent load and current regulation, resulting in very stable LED current over the useful life of the
battery and over the full operating temperature range. The LED current can be adjusted from 100% down to 10% of the set
value by applying a dc voltage to the ADJ pin and down to 1% by applying a PWM signal. An on-chip LED protection circuit
also allows output current to be reduced linearly above a predetermined threshold temperature using an external thermistor
at the TADJ pin. External resistors set nominal average LED current and coil peak current independently. The device can
be shut down by applying a continuous low level dc voltage to the ADJ pin.
Features
Applications
Typical Application Circuit
BUCK/BOOST MODE DC-DC CONVERTER FOR LED DRIVING WITH 700mA OUTPUT AND CURRENT
2.5V to 15V Input Voltage Range
Up to 700mA output current
Typical efficiency
User-defined thermal control of LED
output current using external thermistor
High output current stability over input
voltage and temperature
12μA typical standby current
LED current adjustable from 100%
down to 2%
Adjustable Soft-Start
Capable of driving 3 LEDs in series
High power LED flashlights
LED back-up lighting
General LED lighting
#. Using standard external components as specified under electrical characteristics. Efficiency is dependent upon external component types and
values. Higher efficiency is possible with alternative coils.
#
>80%
www.diodes.com
1 of 17
Pin Assignments
DFN4030-14 Package(Bottom View)
DFN4030-14 with Exposed Pad
Diodes Incorporated
45° chamfer denote Pin 1
A Product Line of
1.5W @ T
0.50mm pitch
4mm x 3mm
(Top View)
A
= 70°C
© Diodes Incorporated
ZXLD1322
CONTROL
April 2010

Related parts for ZXLD1322DCCTC

ZXLD1322DCCTC Summary of contents

Page 1

BUCK/BOOST MODE DC-DC CONVERTER FOR LED DRIVING WITH 700mA OUTPUT AND CURRENT Description The ZXLD1322 is an inductive DC-DC converter, with an internal switch, designed for driving single or multiple LEDs in series total of 700mA output ...

Page 2

Block Diagram ZXLD1322 Document number: DS32166 Rev Product Line of Diodes Incorporated www.diodes.com ZXLD1322 April 2010 © Diodes Incorporated ...

Page 3

Pin Description Name Pin # Adjust input • Leave floating, or connect to V • Drive with dc voltage. (50mV<V ADJ 1 of set value. (DC brightness control mode) • Drive with low frequency (200Hz) PWM control signal to gate ...

Page 4

Absolute Maximum Ratings Symbol Parameter Operating Temperature T OP Storage Temperature T ST Junction Temperature T J Package Power Dissipation P TOT DFN14 with Exposed Pad: 4mm x 3mm, 0.5mm Pitch DC-DC Converter Supply Voltage (VIN) -0.3V to +15V ADJ ...

Page 5

Electrical Characteristics (Test conditions: V DC-DC Converter Supply Parameters Symbol Parameter Supply Voltage V IN Supply voltage for start-up(b) V IN(Start) Under-voltage detection threshold normal operation to start-up mode Under-voltage detection threshold start-up mode ...

Page 6

Switching NPN Transistor Symbol Parameter Average continuous switch current I SW Maximum base current into switch I BON(max) transistor from internal drive circuit Base current into switch transistor I using external resistor (R BON BIAS pin to ground Collector-Emitter breakdown ...

Page 7

LED Thermal Control Circuit (T ADJ Symbol Parameter Upper threshold voltage VT ADJH Lower threshold voltage VT ADJL Trans conductance Gm (TADJ) ΔI /ΔV OUT TADJ Output Current Regulation Parameters Symbol Parameter Minimum output/ LED current I OUT ΔI Output ...

Page 8

Device Description The ZXLD1322 is a buck/boost mode inductive DC-DC converter, with an internal switch, designed for driving single or multiple LEDs in series total of 700mA output current. Depending upon supply voltage (V drop (V ) ...

Page 9

ADJ pin The ADJ pin is connected to the internal 500mV reference (V reference voltage and defines nominal 100% LED current. The ADJ pin can be overdriven with an external dc voltage between 50mV and 500mV to reduce the LED ...

Page 10

Application Notes Setting Peak Coil Current The peak current in the coil is set by the resistor (RSENSE) between the switch emitter and ground according to: 50mV I SWPEAK = R SENSE The minimum peak current will depend on operating ...

Page 11

PWM Control A wider dimming range can be achieved by applying a PWM control signal to the ADJ pin to turn the device on and off, giving an average output current proportional to the duty cycle of the control signal. ...

Page 12

The TADJ pin of the device has a voltage threshold of 75mV nominal, which is derived from the reference voltage V the voltage ( the TADJ pin is held above the threshold, the thermal compensation current will be ...

Page 13

Typical Operating Conditions Inductive converters can operate in either CONTINUOUS mode, where current always flows ithe inductor, but rises during the ON period and falls during the OFF period, or DISCONTINUOUS mode, where the current falls to zero during the ...

Page 14

ON phase, the current can still be established when the supply is less than the LED forward drop. Hence this circuit will work at supply voltages above and below the forward LED drop. This mode is useful for example ...

Page 15

... The bottom of the thermistor must be coupled very closely to ground, as the TADJ pin varies the LED current from 100 for a voltage change of only 25mV, so any noise on the bottom of the thermistor will seriously affect the accuracy of the Thermal Protection circuit. Ordering Information Reel Size Device (mm) ZXLD1322DCCTC 33.02 ZXLD1322 Document number: DS32166 Rev Product Line of Diodes Incorporated Reel Width ...

Page 16

Package Outline – DFN4030-14 E PIN 1 DOT BY MARKING DIM Inches Min Max Min A 0.0315 0.0354 0.80 A1 0.00 0.002 0.00 A3 0.008 REF. b 0.0079 0.0118 0.20 D 0.1555 0.1594 3.95 Note: Controlling dimensions are in millimeters. ...

Page 17

DIODES INCORPORATED MAKES NO WARRANTY OF ANY KIND, EXPRESS OR IMPLIED, WITH REGARDS TO THIS DOCUMENT, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE (AND THEIR EQUIVALENTS UNDER THE LAWS OF ANY ...

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