zxlb1600 Zetex Semiconductors plc., zxlb1600 Datasheet

no-image

zxlb1600

Manufacturer Part Number
zxlb1600
Description
Lcd Bias Boost Converter
Manufacturer
Zetex Semiconductors plc.
Datasheet

Available stocks

Company
Part Number
Manufacturer
Quantity
Price
Part Number:
ZXLB1600
Manufacturer:
ZETEX
Quantity:
20 000
LCD AND OLED BIAS BOOST CONVERTER - STN, CSTN SCREENS
DESCRIPTION
The ZXLB1600 inductive switching boost converter
accepts an input voltage of between 1.6V and 5.5V and
provides an adjustable output voltage of up to 28V for
LCD and OLED bias. The device contains an output
switch and a second switch to isolate the coil from the
input to provide true isolation in shutdown mode. The
output can be adjusted by means of an externally
applied dc voltage, a PWM control signal, or external
feedback resistors and can supply typically 10mA of
output current at maximum output voltage. Higher
current is available at lower output voltages.
The input voltage range accepts a number of battery
solutions, including dual dry cell and single Li-Ion cells
and PFM operation mode allows the output to be
regulated with high efficiency under light or no load
conditions. The switching frequency range permits the
use of miniature surface mount inductors.
A low battery comparator is provided to indicate when
the input voltage has fallen to within ±2% of a preset
threshold. This threshold is set internally , but can be
adjusted externally to any voltage within the supply
voltage range.
TYPICAL APPLICATION CIRCUIT
ISSUE 3 - SEPTEMBER 2003
1
FEATURES
APPLICATIONS
Wide input voltage range: 1.6 to 5.5V
Adjustable output voltage up to 28V, using PWM
or analog control voltage
Internal PWM filter
True shutdown (output isolated from input)
Internal output switch and current sense
Low quiescent current: (75 A max)
5 A (max) shutdown current (including low
battery comparator)
Up to 500kHz switching frequency
High efficiency
Small MSOP10 package
Low external component count
PDAs
Mobile phones - OLED sub displays
Digital cameras
Portable internet appliances
Palmtop computers
GPS terminals
ZXLB1600
S E M I C O N D U C T O R S

Related parts for zxlb1600

zxlb1600 Summary of contents

Page 1

... LCD AND OLED BIAS BOOST CONVERTER - STN, CSTN SCREENS DESCRIPTION The ZXLB1600 inductive switching boost converter accepts an input voltage of between 1.6V and 5.5V and provides an adjustable output voltage 28V for LCD and OLED bias. The device contains an output switch and a second switch to isolate the coil from the input to provide true isolation in shutdown mode ...

Page 2

... ZXLB1600 ABSOLUTE MAXIMUM RATINGS (Voltages to GND unless otherwise stated) Output voltage Input voltage Switch output current Power dissipation Operating temperature Storage temperature Junction temperature ELECTRICAL CHARACTERISTICS Test conditions unless otherwise stated: V Symbol Parameter General (1) V Input voltage IN I Supply current Shutdown ...

Page 3

... (6) V switched from high to low EN V falling IN BLT V rising IN Output ‘on’ 0.5mA BLOL Output ‘off’ 29V BLOH Output ‘off’ 3 ZXLB1600 Min Typ Max Units 1. ppm ADJ (NOM) - 100 % IN 4 kHz 52 ...

Page 4

... Low battery flag output: open drain (active low for low battery voltage) Active when EN is high or low Ground Voltage feedback pin for output (threshold 1.23V) Low battery flag threshold adjust input (threshold 1.21V) TEMPERATURE 4 PART MARK RANGE ZXLB1600 ZXLB1600 ISSUE 3 - SEPTEMBER 2003 ...

Page 5

... This maintains stable and efficient operation. ISSUE 3 - SEPTEMBER 2003 ZXLB1600 Setting output voltage With external voltage The output voltage is equal to the voltage present on the 'ADJ' pin of the device multiplied by the internal resistor network factor (R1+R2)/R1 ...

Page 6

... D x 28V Gated PWM operation The internal circuitry of the ZXLB1600 is turned off when no signal is present on the 'EN' pin for more than 120 s (nominal). A low frequency signal applied to the EN pin will therefore gate the device 'on' and 'off' at the ...

Page 7

... Bottom: Enable input (1V/div), Top: Output voltage (10V/div) Plot 4 Operating waveforms at max output voltage 10mA load Bottom: LX Output (10V/div), Top: Output voltage (50mV/div ac) Plot 6 Load rejection Bottom: Load current (1mA/div), Top: Output voltage (0.1V/div ac) 7 ZXLB1600 ...

Page 8

... ZXLB1600 TYPICAL OPERATING CHARACTERISTICS (Continued and ISSUE 3 - SEPTEMBER 2003 ...

Page 9

... TYPICAL OPERATING CHARACTERISTICS (Continued) ISSUE 3 - SEPTEMBER 2003 and ZXLB1600 ...

Page 10

... ZXLB1600 TYPICAL OPERATING CHARACTERISTICS (Continued and ISSUE 3 - SEPTEMBER 2003 ...

Page 11

... APPLICATION NOTES Adjusting output voltage When connected as shown in the typical application circuit, the ZXLB1600 will produce a nominal output voltage of 28V. This can be adjusted by one of the three methods described below. 1) Output voltage adjustment by external resistors The internal reference and resistor divider network R1 and R2 set a nominal output of 28V ...

Page 12

... PWM signal is applied. Negative output The ZXLB1600 can be used to provide a negative output voltage (in addition to the normal positive output) as shown in the application circuit below. In this circuit, the external resistors are used to set the output voltage to 22V as described in the previous section ...

Page 13

... Small schottky diodes such as the BAT54 are suitable for use with the ZXLB1600 and this diode will give good all round performance over the output voltage and current range. At lower output voltages, a ...

Page 14

... ZXLB1600 Increased efficiency If isolation of the coil from the supply is not needed, the high side of this can be connected directly to VIN to improve efficiency. This prevents power loss in the internal PMOS switch and typical efficiency gains of 5% can be achieved. (See efficiency vs. load curves). Some ...

Page 15

... Notes: ISSUE 3 - SEPTEMBER 2003 15 ZXLB1600 ...

Page 16

... ZXLB1600 PACKAGE OUTLINE Controlling dimensions are in millimeters. Approximate conversions are given in inches © Zetex plc 2003 Europe Zetex plc Zetex GmbH Fields New Road Streitfeldstraße 19 Chadderton D-81673 München Oldham, OL9 8NP United Kingdom Germany Telephone (44) 161 622 4444 Telefon: (49 ...

Related keywords