Datasheet

C
RES1
C
RES2
COIL
AC1
AC2
VRECT
GND
C
MOD
C
RES1
C
RES2
COIL
AC1
AC2
VRECT
GND
R
MOD
bq51013B
SLUSB62A –MARCH 2013–REVISED OCTOBER 2013 www.ti.com
Table 4.
Message Value Condition
Unknown 0x00 AD > 3.6V
Charge Complete 0x01 TS/CTRL = 1, or EN1 = 1, or <EN1 EN2> = <11>
Internal Fault 0x02 T
J
> 150°C or R
ILIM
< 100Ω
Over Temperature 0x03 TS < V
HOT
, TS > V
COLD
, or TS/CTRL < 100mV
Over Voltage 0x04 Not Sent
Over Current 0x05 NOT USED
Battery Failure 0x06 Not Sent
Reconfigure 0x07 Not Sent
No Response 0x08 VRECT target doesn't converge
Status Outputs
The bq5101xB has one status output, CHG. This output is an open-drain NMOS device that is rated to 20V. The
open-drain FET connected to the CHG pin will be turned on whenever the output of the power supply is enabled.
Please note, the output of the power supply will not be enabled if the V
RECT-REG
does not converge at the no-load
target voltage.
WPC Communication Scheme
The WPC communication uses a modulation technique termed “back-scatter modulation” where the receiver coil
is dynamically loaded in order to provide amplitude modulation of the transmitter's coil voltage and current. This
scheme is possible due to the fundamental behavior between two loosely coupled inductors (e.g. between the Tx
and Rx coil). This type of modulation can be accomplished by switching in and out a resistor at the output of the
rectifier, or by switching in and out a capacitor across the AC1/AC2 net. Figure 29 shows how to implement
resistive modulation.
Figure 29. Resistive Modulation
Figure 30 Shows how to implement capacitive modulation.
Figure 30. Capacitive Modulation
The amplitude change in Tx coil voltage or current can be detected by the transmitters decoder. The resulting
signal observed by the Tx is shown in Figure 31.
22 Submit Documentation Feedback Copyright © 2013, Texas Instruments Incorporated
Product Folder Links: bq51013B