ZXLD1615/1601 boost converter for
LCD-OLED bias and DC-DC suppl
New product in formation f rom ZetexJu l y 2 0 0 4
FeaturesBenefits
• Internal 30V NMOS switch
• True analog output voltage control
• High efficiency: 80% typical
• 2.5V to 5.5V supply range
• Low quiescent current
• TSOP23-5 and SC70-6 packages
• ZXLD1615 is pin compatible to LT1615
Applications
• LCD and OLED biasing
• Varactor diode biasing
• DC-DC boost converter
• Minimum external components
• Reduced flicker
• Longer battery life
• Compatible with Li-Ion battery
• Longer battery life
• Minimum board area
• Alternate source to LT1615
• Cell phones
• Digital cameras
• PDAs
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Functional Description
www.zetex.com
The ZXLD1615 and ZXLD1601 are PFM
inductive DC-DC boost converters. They are
particularly suited to provide bias voltages for
LCD and OLED displays. Up to 28V can be
generated from an input voltage between 2.5
and 5.5V.
The switch is integrated on chip together with
the peak current sense resistor. An output
current of 10mA is available at 28V, with
proportionally higher currents at lower
voltages.
The output voltage is set by 2 external
resistors connected to the feedback input.
PWM control at the enable input can be used
to adjust this voltage. An on chip filter
enables flicker free control at PWM
frequencies above 10kHz, or normal gated
control below 1kHz.
DescriptionVin (V)
Output
voltage
Typical
quiescent
current (µA)
Quiescent current is typically 60µA. At
shutdown the maximum current is 100nA.
The ZXLD1615ET5 is packaged in a low
profile TSOT23-5 package. Maximum
package height is 1mm. The ZXLD1601 is
packaged in a small footprint SC70-6
package.
The ZXLD1615ET5 is pin compatible with
LT1615, TPS61040 and SP6690. In many
applications the ZXLD1615 can replace
these parts. Input voltage range is the main
difference. Most other parameters are the
same or very close.
Shutdown
current (nA)
Efficiency
%
Switching
frequency
(kHz)
Package
ZXLD1615ET5
ZXLD1601H6
2.5 to
5.5
2.5 to
5.5
Up to 28V6010080600TSOT23-5
Up to 28V6010080600SC70-6
Applications Information
The data sheets contain information about the operation of each converter and how the
internal blocks function. The data sheets also contains additional applications information
on:
• 1cell Li-Ion to 3.3V SEPIC converter
• 1cell Li-Ion to 5V SEPIC converter
• Triple output boost converter for LCD or OLED bias
• Selecting inductors, capacitors and diodes.
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D1
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www.zetex.com
VIN
OFF
ON
EN
C1
ZXLD 1615
Competition
There are several competitive solutions
available for LCD and OLED biasing. Zetex
has chosen to make a SOT23-5 pin
compatible version of the industry leading
LT1615. This should enable an easy
acceptance of the part and a high chance of
being considered as an alternative source.
Other SOT23-5 pin compatible parts are:
LX
FB
GND
R2
C2
R1
The ZXLD1601H6 is one of the smallest
packages available for this function. This will
be of interest where space is a premium.
Other parts which are similar but not pin
compatible are:
Maxim – MAX1605 in SOT23-6
Micrel – MIC2141
Sipex – SP6690
TI – TPS61040
Zetex is price competitive with respect to all
these suppliers.
The main performance attributes of the
ZXLD1615 compared with competition are
shown in the table.
CompanyZetexLinear TechTexas InstSipex
Part numberZXLD1615LT1615TPS61040SP6690
Conversion modePFMPFMPFMPFM
Supply input voltage (V)2.5 to 5.51.2 to 151.8 to 61 to 15
Output voltage (V)28342830
Switch current (mA)320 typ350 typ400 typ350 typ
Quiescent current (µA)60 typ20 typ28 typ20 typ
Standby current (µA)0.1 max1 max1 max1 max
Feedback ctrl voltage (V)1.0 ±2%1.23 ±2%1.233 ±2%1.22 ±4%
Efficiency at 3V (%)80808080
Operating temperature (ºC)-40 to +85-40 to +85-40 to +85-40 to +85
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Potential customers to look for
www.zetex.com
• LCD or OLED module manufacturers
where a complete display system is
provided to end users. (This is also an
opportunity for the ZXLD1937 when
backlighting is included in the module.)
• Manufacturers of handheld equipment
incorporating color LCD or OLEDs
where bias is generated externally to the
display module. This typically includes
digital cameras, mobile phones, PDAs,
GPS and portable test equipment.
• Users of LT1615 where the supply
voltage range is within 2.5 to 5.5V.
Pricing
As a guide :
ZXLD1615ET5TA is $0.53 at 1k and $0.41
at 10k.
ZXLD1601H6TA is $0.65 at 1k and $0.50 at
10k
Typical applications include:
LCD bias generator
OLED bias generator
Varactor diode bias generator
DC-DC boost for hand held instruments
PIN diode bias generator
As always with all new products please ask
if you have any pricing questions.
Ordering Information
• #ZXLD1615ET5TA – samples available now
• #ZXLD1601H6TA – samples available now
• ZXLD1615ET5TA – production available now
• ZXLD1601H6TA – production available now
Do you have a key customer
you’d like to send samples to?
Contact us at:
europe.sales@zetex.com
asia.sales@zetex.com
usa.sales@zetex.com
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www.zetex.com
For lead free product prefix the part number with U.
i.e. UZXLD1615ET5TA
This convention will apply until Zetex is completely lead free, at which time the U prefix will
not be required.
TA reels contain 3000 parts. Where larger reels are required the TC reel contains 10,000
parts.
Support
• Datasheets - the ZXLD1615 and ZXLD1601 datasheets are available now on the Zetex
web site:
• Application note – Several applications are described in the product datasheets. Future
application notes will be publicized as they become available
• Evaluation board for ZXLD1615 available for qualified customers.
Conclusion
As with many Zetex products, what we show on our collateral is not the limit of what we can
achieve. If you see other product opportunities, please let us know. Your local Zetex office
will be pleased to offer any technical support, pricing and sample requests.