Olimex Support Forum

DUINO => MAPLE => Topic started by: BMWMPower on June 11, 2013, 12:52:01 AM

Title: Analogue voltage
Post by: BMWMPower on June 11, 2013, 12:52:01 AM
Maybe I am looking over it in the manual. But what is the max voltage on the analogue in pins? 5V i hope?
Title: Re: Analogue voltage
Post by: LubOlimex on June 11, 2013, 02:24:53 PM
Hey BMWMPower,

The easiest way to be 100% sure which pins are 5V compatible is to cross-check the pins of the processor and compare to the schematic of OLIMEXINO-STM32.

Refer to the table on pages 28-32 of this document: http://www.st.com/web/en/resource/technical/document/datasheet/CD00161566.pdf (http://www.st.com/web/en/resource/technical/document/datasheet/CD00161566.pdf).

Best regards,
Lub/OLIMEX
Title: Re: Analogue voltage
Post by: BMWMPower on June 11, 2013, 10:26:58 PM
It looks like that it are 12-bit 3.6V ADC's. Ai...how can I connect 5V sensors (motorcycle) on the pins? Do i have to build an converter??
Title: Re: Analogue voltage
Post by: LubOlimex on June 14, 2013, 08:44:43 AM
Hey BMWMPower,

"Two 12-bit analog-to-digital converters are embedded into STM32F103xx performance line
devices and each ADC shares up to 16 external channels, performing conversions in singleshot or scan modes."

3.6 if the maximum allowed, 2.5 is the minimum detected by thee ADC, 3.3V is the recommended voltage. There are lot of guides available in the Workd Wide Web - just search for something like "5v sensor on a 3.3v adc". You can build own converter or use IC.

Best regards,
Lub/OLIMEX