CLRC663 Datasheet, PDF (24/132 Pages) NXP Semiconductors – Contactless reader IC

NXP Semiconductors
CLRC663
Contactless reader IC
8.4.4 I²C-bus interface
8.4.4.1 General
An Inter IC (I²C) bus interface is supported to enable a low cost, low pin count serial bus
interface to the host. The implemented I²C interface is mainly implemented according the
NXP Semiconductors I²C interface specification, rev. 3.0, June 2007. The CLRC663 can
act as a slave receiver or slave transmitter in standard mode, fast mode and fast mode
plus.
The following features defined by the NXP Semiconductors I²C interface specification,
rev. 3.0, June 2007 are not supported:
• The CLRC663 I2C interface does not stretch the clock
• The CLRC663 I2C interface does not support the general call. This means that the
CLRC663 does not support a software reset
• The CLRC663 does not support the I2C device ID
• The implemented interface can only act in slave mode. Therefore no clock generation
and access arbitration is implemented in the CLRC663.
• High speed mode is not supported by the CLRC663
MICROCONTROLLER
PULL-UP
NETWORK
Fig 16. I²C-bus interface
PULL-UP
NETWORK
READER IC
SDA
SCL
001aam000
SDA is a bidirectional line, connected to a positive supply voltage via a pull-up resistor.
Both lines SDA and SCL are set to HIGH level if no data is transmitted. Data on the
I²C-bus can be transferred at data rates of up to 400 kbit/s in fast mode, up to 1 Mbit/s in
the fast mode+.
If the I²C interface is selected, a spike suppression according to the I²C interface
specification on SCL and SDA is automatically activated.
For timing requirements refer to Table 248 “I²C-bus timing in fast mode and fast mode
plus”
8.4.4.2 I²C Data validity
Data on the SDA line shall be stable during the HIGH period of the clock. The HIGH state
or LOW state of the data line shall only change when the clock signal on SCL is LOW.
CLRC663
Product data sheet
COMPANY PUBLIC
All information provided in this document is subject to legal disclaimers.
Rev. 3.3 — 3 April 2012
171133
© NXP B.V. 2012. All rights reserved.
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