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AS8202B

Datasheet - Detailed Descr i p ti on

Figure 10. Bus Guardian Clock Setup

The bus guardian clock (XIN1/XOUT1) supports driving a quartz crystal oscillation, as well as a clock input by an external oscillator.

7.2.4 Built-in Characteristics

7.3 TTP Bus Interface

The AS8202B contains two TTP bus units, one for each TTP channel, building the TTP bus interface. Each TTP bus channel contains a

transmitter and a receiver and can be configured to be either in the asynchronous or synchronous mode of operation. Note that the two channels

(channel 0 and channel 1) can be configured independently for either of these modes.

The drivers of the TxD and CTS pins are actively driven only during a transmission window, all the other time the drivers are switched off and the

weak pull resistors are active. External pull resistors must be used to define the signal levels during idle phases.

Note: The transmission window may be different for each channel.

Table 8. Characteristics

Symbol

Pin

Parameter

Min

Typ

Max

Unit

Note

Tosc_startup1

XIN1/XOUT1

Oscillator startup time

(Bus Guardian clock)

20

ms

Frequency: 16MHz

Table 9. Bus Interface Connections

Pin Name

Tx inactive

TxD[0]

weak pull-up

CTS[0]

weak pull-down

TxD[1]

weak pull-up

CTS[1]

weak pull-down

16 M H z

Rd

Rf

Ce x t

Ce x t

16 M H z

sq u a r e

wa v e

External quartz

External oscillator