®
RT5081
Highly-Integrated Sub-PMIC for Mobile Applications
General Description
50kHz. The RT5081 can also support torch/strobe
The RT5081 is a highly-integrated smart power
management IC, which includes a single cell Li-Ion/Li-
Polymer switching battery charger, a USB Type-C &
Power Delivery (PD) controller, dual Flash LED current
sources, a RGB LED driver, a backlight WLED driver, a
display bias driver and a general LDO for portable devices.
backlight modes with regulated constant current for front
camera screen flash applications.
The display bias driver (DB) is implemented with a single-
inductor boost and an inverting charge pump to achieve a
smaller PCB area, compared with a dual-inductor boost
converter. The display bias driver is used to provide a
negative voltage output (VDB_NEG) through the
The switching charger integrates a synchronous PWM
controller, power MOSFETs, input current sensing and
input current regulation, high-accuracy voltage regulation,
and charge termination circuitry. Besides, the charge
current is regulated through the integrated sensing
resistors. It also features USB On-The-Go (OTG) support.
DB_NEGVOUT pin and a positive voltage output (VDB_POS
)
through the DB_POSVOUT pin. The negative voltage
output comes from the boost converter output voltage
(VDB_BST) at theDB_BSTVOUT pin, and the positive voltage
output is from theDB_POSVOUT voltage passing through
an LDO to reduce power noise. The VDB_POS and VDB_NEG
voltage ranges can be programmed from 4V to 6V and
from −4V to −6V with a resolution of 50mV, respectively.
These two output rails, usually connected to a Source
Driver IC, can support up to 50mAoutput current capability
to drive up to 10" TFT-LCDpanels.
The USB Type-C & PDcontroller complies with the latest
USB Type-C and PD standards. It integrates a complete
Type-C transceiver including the Type-C termination
resistors, Rp and Rd, and enables the USB Type-C
detection including attach and orientation. It also integrates
the physical layer of the USB BMC power delivery protocol,
allowing power transfers and role swaps. The BMC PD
function provides full support for alternate modes on the
USB Type-C standard.
The LDO can be used to supply power to an Eccentric
Rotating Mass (ERM) Motor in mobile phones and other
hand-held devices. The output voltage is programmable in
the range of 1.6V to 4V via the I2C interface.
Dual independent current sources supply for each flash
LED. The power for the current sources in strobe mode
are from the CHG_VMID pin, which is supplied from the
charger in reverse boost mode, the same operation as
OTGmode of the charger. The high-side current sources,
allowing for grounded-cathode connection for LEDs,
provide strobe mode current levels from 50mA to 1.5A in
a 12.5mA step or from 25mA to 750mA in a 6.25mA step
and torch mode current levels from 25mA to 400mA in a
12.5mA step. The two channels can support totally up to
2.5A.
The RGB LED driver is a 4-Channel smart LED string
controller to drive 3 channels of LEDs with a sink current
of up to 24mAand a CHG_VINpower good indicator with
a sink current of up to 6mA. All channels can be set
independently via the I2C interface, and are provided with
three operation modes: Register Mode, PWM Mode and
Breath Mode.
The RT5081 is available in a WL-CSP-93B 4.22x4.32 (BSC)
package.
The backlight WLED driver supports up to a 29V output
voltage for 4 channels of 8 series WLEDs. Each channel
supports up to 30mAof current capability with 2048 current
steps in exponential or linear mapping curves. The backlight
brightness is controlled by the I2C interface and an external
PWM control. The PWM frequency range is from 50Hz to
Applications
ꢀ Cellular Telephones
ꢀ Personal InformationAppliances
ꢀ Tablet PCs
ꢀ Portable Instruments
Copyright 2018 Richtek Technology Corporation. All rights reserved.
©
is a registered trademark of Richtek Technology Corporation.
DS5081-00 January 2018
www.richtek.com
RICHTEK [ RICHTEK TECHNOLOGY CORPORATION ]
