pca8885 NXP Semiconductors, pca8885 Datasheet - Page 9

• Manufacturer Part Number: pca8885
• Description: Capacitive 8-channel Proximity Switch With Auto-calibration And Very Low Power Consumption
• Manufacturer: NXP Semiconductors

NXP Semiconductors
PCA8885
Objective data sheet
9.4 Command: read-sensor
During sleep mode, the register configuration is maintained and the device remains
responsive to I
guaranteed, as there is no limitation on the duration of the sleep mode. Therefore the
analog part has to perform a normal start-up phase, including the fast start procedure for
the CPC capacitor charging.
Sleep mode is entered when the sleep command is received from the system controller or
when the SLEEP pin is set to HIGH. Resume is done by the wake-up command, or by
setting the SLEEP pin to LOW.
The hardware sleep mechanism using the SLEEP pin and the software sleep mechanism
using the sleep or wake-up commands are independent of each other:
The read-sensor command is the main transaction to read the actual state information of
the sensor state register SENS.
If the R/W bit (LSB of the I
the PCA8885 regards the transaction as the read-sensor command. The read-sensor
command transaction supports a repeated reading of the SENS register (see
on page
return their SENS register content in a single transaction
The protocols for the repeated read mode and the alternating read mode are described in
Section 13.7 on page
•
•
If the device was put to sleep using the sleep command, a wake-up command
resumes the operation. It cannot be resumed by activating the SLEEP pin.
If the device was put to sleep by setting pin SLEEP to HIGH, then pin SLEEP must be
set to LOW to resume operation. It cannot be resumed with the wake-up command.
14). When two circuits are used in a cascaded configuration, they alternately
2
C commands. The charges in the CPC capacitors however cannot be
All information provided in this document is subject to legal disclaimers.
Rev. 1 — 24 November 2011
21.
Capacitive 8-channel proximity switch with auto-calibration
2
C slave address byte, see
Table 11 on page
PCA8885
© NXP B.V. 2011. All rights reserved.
21) is set logic 1
Section 10.3
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