 |
|
Richtek power IC solutions for wearable applications |
|
Wearable devices are small, thin and light-weight, often powered
by lithium-ion coin cell batteries. As more functionality is
added to wearable devices, extending battery life becomes a
key factor for power management design. Richtek has been developing
a new range of power solutions specifically targeted for wearable
designs, like AMOLED display drivers, ultra low Iq DC/DC converters,
battery chargers designed for low capacity Li-Ion batteries,
wireless power receivers with embedded charger, and tiny fuel
gauge ICs. |
|
|
Many wearable solutions use AMOLED displays due to their low
power consumption and high contrast ratio display. AMOLED panel
drive is extremely sensitive to noise, and requires special
designed power ICs to provide very precise and noise free voltages.
|
|
RT4723 is a dual output AMOLED
Power IC with integrated boost converter for Vpos and
a charge pump for Vneg in small CSP-15B 1.39x2.07 package, specifically
designed for 1’’ to 2’’ panels in battery-powered wearable/portable
applications. The total solution has better light load efficiency
compared to competitor solutions and features an extremely small
PCB footprint. |
|
|
Wearable applications that contain MCUs for computing require
lower voltage rails for the core supply, like 0.7V to 1.2V.
The load on these rails will be idle for most of the time with
a sudden higher current during data processing, storage or transmission.
This application requires buck converters with very low quiescent
current for low power consumption during idle mode, but also
good load transient behaviour and high efficiency during the
high load condition. The RT5706 and RT5707/A family
is designed to achieve 360nA idle mode operation, while
the HCOT control ensures fast transient behaviour. The Low Rdson
internal MOSFETs provides high efficiency during pulse loads.
RT5706 contains an extra load switch which can be used to disable
subsystems for ultra low power standby mode. The tiny CSP 8B-0.9x1.6
package ensures a small application footprint.
RT5706 and RT5707 are sampling now. For more information, please
contact your nearest Richtek sales office. |
|
|
Sensitive devices like accelerometers sensors and touch-screen
controllers require stable noise-free supplies, and these will
normally use low drop linear regulators. Richtek’s low Iq LDO’s
like
RT9073A are highly suitable for
wearable applications: They have 1μA ground current,
but can also provide quick transient response due to their dynamic
ground current control. Stable with only 1μF output capacitors
and housed in tiny 1x1 ZQFN packages ensures small application
footprint. |
|
|
Charging various sizes low capacity Li-Ion battery cells requires
a charger IC with a wide charge current adjustment range. At
the same time all charge parameters like pre-charge current
and end-of-charge current need to track with the programmed
current. Another important parameter is the charger leakage
current in sleep mode. |
|
RT9527GQW is specifically designed
for charging low capacity Li-Ion batteries with a charge current
adjustment range between 10mA to 600mA which makes
it suitable for a wide range of small size batteries. It features
accurate 4.2V CV regulation voltage, 10% ratio tracking pre-charge
and end-of-charge current, 300nA sleep mode, build-in safety
timer and NTC sense, all integrated in a small 2x2 QFN package.
This 28V input rated part can be used in virtually any charger
application for small hand-held and wearable solutions. |
|
|
Remaining battery capacity can be accurately sensed by means
of the battery gauges which make use of the battery voltaic
model. These systems measure the dynamic battery voltage and
calculate the Relative State Of Charge. This method does not
suffer accumulation errors which are typical for coulomb counting
systems.
RT9428WSC reports RSOC to the system
controller via I2C and consumes only 1μA in sleep mode.
It requires only one capacitor, and is housed in a tiny CSP8B
1.6x1.52mm package for smallest footprint. |
|
Please download our latest
wearable product selection guide
to find a full overview
of parts suitable for
wearable and battery powered designs.
|
|
New simulation models released on Richtek Designer™
|
|
|
|
|
New Products |
 |
RT5788A/B (PSM/PWM) is a 4A Iout, 2.5V-6Vin, 1.5MHz,
35µA IQ ACOT Synchronous Buck Converter
in a SOT-23-8 package. Operating up to 100% duty cycle
mode, RT5788A/B features high efficiency and ultra-fast
transient response. It is suitable for handheld devices,
STB, cable modem, SSD & HDD, etc.
⇒
See other ACOT Buck converters
⇒
Get Free RT5788A/B Sample Now |
 |
RT5789A/B (PSM/PWM) is a 6A, Iout, 2.5V-6Vin, 1.5MHz,
35µA IQ ACOT Synchronous Buck Converter
in SOT-23-8 and UDFN-8L 2.5x2 packages. Integrated 25mΩ
switch and 20mΩ synchronous rectifier, RT5789A/B features
extremely low quiescent current to achieve high light
load efficiency. The ACOT control architecture allows
ultrafast transient response and reduces external component
size. Highly suitable for core supplies powered from
5V or 3.3V rails.
⇒
See other ACOT Buck converters
⇒
Get Free RT5789A/B Sample Now |
 |
RTQ2102A-QA is an automotive AEC-Q100 grade 1 qualified
1.5A, 3V-6Vin, 30µA IQ ACOT Synchronous
Buck Converter in a WDFN-8L 3x3 package. Operating from
-40°C to 125°C, RTQ2102A provides up to 2.7MHz operation
frequency to minimize external component size. The ACOT
topology allows transient response to be optimized over
a wide range of loads. It is ideal for automotive infotainment,
automotive instrument clusters & HUD, car connectivity,
etc.
⇒
Get Free RTQ2102A-QA Sample Now |
 |
RT4813 is a 1.8V-5.5Vin, up to 96% high efficiency
Boost Converter in a UQFN-9L 2x2 package. Featuring
programmable average output current limit from 0.55A
to 3.1A, RT4813 has less than 1µA quiescent current
in shutdown mode, which maximizes battery life. It provides
a compact solution for systems using advanced single-cell
Li-ion battery chemistries.
⇒
Get Free RT4813 Sample Now |
|
|