AT7908E
Oscillator
Xtalin and Xtalout are IOs of an internal inverting oscillator. To use the internal oscillator,
the quartz must be connected between Xtalin and Xtalout pins.
To drive the device with an external clock source, Xtalin must be driven by clock signal
and Xtalout must be left unconnected. The maximum operating frequency of the oscilla-
tor, in open-loop mode(without crystal) with 6 pF load on Xtalout at worst condition
(Process slow, temperature = 145°C, Power supply = 4.5V ) is 60 MHz.
The IO level of Xtalin and Xtalout are CMOS levels.
The internal clock could be put on off condition with external pins SENA = logical value
1 and TEST = logical value 0.
Reset Specification
The reset pin must be driven low for at least 3 clock cycles ( 190 ns at 16 MHz).
The reset signal must be driven low at power on of the AT7908E for at least 200 ns to
avoid abnormal start condition of the AT7908E device.
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4268D–AERO–11/09
ATMEL [ ATMEL ]
