Final Datasheet
June 19, 2017
Functional Description
TS51224 is a fully-integrated wireless power receiver that can operate as a single-chip solution in proprietary
applications. It can also operate in conjunction with a wireless charger controller or an application microcontroller to
support the Qi, PMA or A4WP standards as well as proprietary standards up to 2W for 5V output and up to 5W for higher
output voltages. Operating in conjunction with TS80002 as a wireless power transmitter and with a charging controller
on the RX side, TS51224 can support bidirectional communication for data upload from the RX to the TX side. A TX to RX
alert or reset function is also included so TS80002 can issue an interrupt or a reset signal to the RX MCU if the RX MCU
becomes unresponsive.
Rectifier
TS51224 includes a high-efficiency rectifier to convert the input AC power signal to a DC output level for powering a
high-efficiency step-down DC-DC converter and an integrated data modulator. The rectifier bridge is built to minimize
power dissipation across load current of interest. The primary side of the bridge can stand-off up to 40V with AC input
running at 6.78MHz. On the secondary side, a capacitive load on the PDC pin is used to filter the voltage signal on both
sides of the bridge rectifier. The integrated data modulator and the external MCU communicate to the transmitter side
using the capacitive modulation scheme.
Integrated Modulator
The integrated Data Modulator can be configured to operate in standalone or bypass mode. In standalone mode, the
integrated modulator sends data messages to the TX side using a proprietary protocol to control the rectified voltage
level on the PDC pin. In bypass mode, the external MCU controls the data packets to the TX side. For example, if the
device is configured for standalone mode at power up, the system can receive power without external MCU support,
and once PDC is high enough to operate the buck regulator and the MCU, the MCU can take over the communication
with the transmitter by bypassing the integrated modulator. Modulator mode reverts back to the standalone mode
when the MCU communication with the transmitter stalls. When the PDC output load current is low (buck regulator is
off), an internal 10mA load is enabled to allow data communication to take place in optimal conditions.
40V Input Buck Regulator
The integrated Buck regulator is a current-mode synchronous step-down power supply with integrated power switches,
internal compensation, and fault protection. It is powered by the DC output of the Wireless power receiver bridge. The
regulator is designed to handle a wide range of input and output voltages. The regulator is optimized for high
efficiency power conversion with low R
DSON
integrated synchronous switches. Low power at light output loads is
attained by the regulator automatic transitions between PFM and PWM modes. The regulator will automatically turn off
when the RX AC power input is removed.
Blocking FET
An integrated low impedance FET in the TS51224 provides blocking from SYSOUT to FB. In cases where AC power is not
applied, the battery is directly connected to SYSOUT. In this condition, the blocking FET is off, preventing conduction
from SYSOUT to PDC. If AC power is applied and PDC is greater than the batter voltage, then the blocking FET will be on
and the SMPS will regulate the SYSOUT voltage.
Charger
TS51224 includes a linear regulator to manage battery charging current. The charger operates by sensing the voltage
drop across a sense resistor and regulating this to a DC value. Battery charging is controlled by the integrated state
machine. When charging at a 1C rate, the SMPS will regulate SYSOUT to be sufficiently higher than VBAT to allow full
charging currents. When the battery is very low (<3.3V), the SMPS will regulate SYSOUT to be equal to 3.3V and the
charger will regulate the battery current to the 0.1C rate.