How can i configure the SC block as band pass filter at 40Khz ?
A single SC block can only generate 1 pole in a transfer function, you
need two poles for a BP filter which takes 2 poles, hence 2 SC blocks.
You could use a single SC block with external R-C HP to create a very poor,
low selectivity BP, not generally speaking a suitable solution.
Please refer application note AN2168 - PSoC 1 Understanding Switched Capacitor Filters. Example project is also provided for BPF.
When you place a BPF filter from module library, you can then right
click it and choose the wizard to configure it.
You can palce a 2 pole or 4 pole BP filter, respectively 2 SC blocks/pole