STYLUS TO HOST SYNCHRONIZATION
A system and method for synchronizing a stylus to a capacitive sense array. The system including a capacitive sense array which includes a plurality of electrodes. A synchronization signal is transmitted to the stylus using the plurality of electrodes. The synchronization signal is transmitted to the stylus by capacitively coupling the stylus to the capacitive sense array.
1 . A method comprising:
providing a plurality of electrodes in a capacitive sense array; and
transmitting a synchronization signal to a stylus using the plurality of electrodes.
2 . The method of claim 1 , further comprising:
transmitting a transmit signal using the plurality of electrodes.
3 . The method of claim 2 , wherein the synchronization signal and the transmit signal are transmitted simultaneously.
4 . The method of claim 2 , wherein the synchronization signal and the transmit signal are different frequencies.
5 . The method of claim 1 , further comprising:
receiving a stylus transmit signal from the stylus using the plurality of electrodes.
6 . The method of claim 2 , wherein the synchronization signal has a first frequency and the transmit signal has a second frequency, and wherein the first frequency is a multiple of the second frequency or the second frequency is a multiple of the first frequency.
7 . The method of claim 1 , wherein the synchronization signal is transmitted to the stylus by capacitively coupling the stylus to the plurality of electrodes.
8 . The method of claim 1 , wherein the stylus is synchronized based on a frequency of the synchronization signal.
9 . The method of claim 1 , wherein the stylus is synchronized based on a phase of the synchronization signal.
10 . The method of claim 1 , wherein the synchronization signal comprises a signal burst and wherein the stylus is synchronized based on a timing of the signal burst.
11 . An apparatus comprising:
a capacitive sense array comprising a plurality of electrodes, wherein the plurality of electrodes is configured to transmit a synchronization signal to a stylus.
12 . The apparatus of claim 11 , wherein the plurality of electrodes is further configured to transmit a transmit signal.
13 . The apparatus of claim 12 , wherein the plurality of electrodes is configured to transmit the synchronization signal and the transmit signal simultaneously.
14 . The apparatus of claim 12 , wherein the synchronization signal and the transmit signal are different frequencies.
15 . The apparatus of claim 11 , wherein the plurality of electrodes is further configured to receive a stylus transmit signal from the stylus.
16 . The apparatus of claim 11 , wherein the synchronization signal is transmitted to the stylus by capacitively coupling the stylus to the plurality of electrodes.
17 . The apparatus of claim 11 , wherein the stylus is synchronized based on a frequency of the synchronization signal.
18 . The apparatus of claim 11 , wherein the stylus is synchronized based on a phase of the synchronization signal.
19 . The apparatus of claim 11 , wherein the synchronization signal comprises a signal burst and wherein the stylus is synchronized based on a timing of the signal burst.
20 . An apparatus comprising:
a controller configured to generate a synchronization signal; and
means for transmitting the synchronization signal to a stylus without using an antenna.