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POWER MANAGEMENT

21

SH3003

POWER MANAGEMENT

Interrupt Interface

The serial communications line to the SH3003 (Pin 14, IO/Int) also serves as the interrupt to the host microcontroller.

The polarity of the interrupt is software programmable using the interrupt polarity bit (bit 6) of the IPol_RCtune register

(R0x11). This pin is asserted for four cycles of CLKout, and then returns to the inactive state.

The interrupt line is used by the Periodic Interrupt/Wake-up Timer to interrupt the host when it reaches its end of

count.

Minimum Bit Period

Minimum Bit Period

(host Asynchronous to

Maximum Bit Period

16MHz

250ns

3.25μs

63.9μs

8MHz

500ns

6.5μs

127μs

2MHz

2μs26μs511μs

Table 3 - Minimum/Maximum Serial Bit Timing