PCA9698使用前咨询

[150973860]

我有个产品想用PCA9698DGG这个芯片扩展IO，只做输出使用，我想请问：

1、由于我MCU引脚有限，只有三根引脚用于扩展，我想接SDA、SCL和RESET，因为只做输出使用，请问OE输出使能引脚可以直接接低电平吗？

2、因为只做输出使用，INT引脚可以不接吗？

3、我扩展IO的目的是模拟多路SPI接口，请问这个芯片的响应速度是否可以满足？（我使用的SPI速度不是很高）

非常感谢！

[guoweisun]

Hi

For your questions please see comment:

1:Please read datasheet describe about OE function:

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• When a LOW level is applied to the OE pin, with OEPOL = 0 (register 2Ah, bit 4) or a
HIGH level is applied to the OE pin, with OEPOL = 1 (register 2Ah, bit 0), all the I/Os
configured as outputs are enabled and the logic value programmed in their respective
OP registers is applied to the pins.
• When a HIGH level is applied to the OE pin, with OEPOL = 0 (register 2Ah, bit 0) or a
LOW level is applied to the OE pin, with OEPOL = 1 (register 2Ah, bit 0), all the I/Os
configured as outputs are 3-stated.

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2:Yes

3:what's your SPI speed?

Thanks!