Regarding NVSRAM H/W deisgn - Forums Re: Regarding NVSRAM H/W deisgn  Dear  Jayaraj ,

Please find the response below

1.  Operating voltage: I am planning to provide 3.3V regulated voltage to the NVSRAM. Is it okay or any suggestions?

CY14B101PA is a 3V (2.7V-3.6V) device so keeping VCC=3.3V is alright. 

2. Controller Interface: My uC operates with 5V.  5V-3.3V & 3.3V-5V converter using transistor (BC848) were used in between the uC & NVSRAM. Is it okay or any suggestions?

As long as logic levels on the nvSRAM's IO pins are maintained , device will work without any issue. When connecting a 5V IO logic standard with 3V logic IO standard, the VIL, VIH and VOL, VOH specs must be properly verified for its compatibility for the logic leveles between the two devices. If logic levels falls within device range, devices will work without any issue.  

3.  3.6V battery Ni-Cd battery, I am planning to provide to NVSRAM, after suitable voltage drop (3.2V), using 2 diodes in series. Is it okay or any suggestions?

As long as VCC stays within 2.7V to 3.6V, device will work properly. 3.2V is ok for the nvSRAM.

4.  I am planning to charge the Ni-Cd battery using 5V supply with a suitable diode & resistor combination. Shall I charge the battery, when connected to NVSRAM, with the presence of 3.3v supply to NVSRAM?

I dont see any issue with this configuration. If you are anticipating any spific condition where you think it may be an issue then please let me know, I can review and let you know the impact if any. Otherwise it ok to use nvSRAM in above configuration as you have mentioned. 

Best Regards,




Tue, 03 Apr 2012 03:58:32 -0600