Diff: ntc_10k_44031.cpp

Revision:

4:d8246c20aed2

Parent:

2:bcfa5a2f21c9

--- a/ntc_10k_44031.cpp	Tue May 25 15:28:17 2021 +0530
+++ b/ntc_10k_44031.cpp	Thu Jul 01 13:41:18 2021 +0530
@@ -18,6 +18,15 @@
 #include "thermistor.h"
 #include "ntc_10k_44031.h"
 
+/* Convert the temperature using Beta factor specified for 44031 10K NTC */
+//#define	NTC_10K_44031_CONVERT_USING_BETA_VALUE
+
+#if defined(NTC_10K_44031_CONVERT_USING_BETA_VALUE)
+#define NTC_10K_44031_RESISTANCE_AT_25C		10000	// 10K
+#define NTC_10K_44031_ROOM_TEMP_IN_KELVIN	298.15
+#define NTC_10K_44031_BETA_VALUE			3694
+#endif
+
 #ifdef DEFINE_LOOKUP_TABLES
 /* 10K NTC look-up table. Values are resistance in ohm for temperature
  * range from -10 to 80C with +/-1C tolerance.
@@ -61,13 +70,20 @@
 
 /*!
  * @brief	Convert the thermistor resistance into equivalent temperature using
- *			Steinhart-Hart equation for 10K 44031 NTC
+ *			Steinhart-Hart equation Or Beta value for 10K 44031 NTC
  * @param	resistance[in] - thermistor resistance
- * @return	Thermistor temperature value
+ * @return	Thermistor temperature value in Celcius
  */
 float ntc_10k_44031rc::convert(const float resistance)
 {
+#if defined(NTC_10K_44031_CONVERT_USING_BETA_VALUE)
+	float temperature;
+	temperature = (1 / ((log(resistance / NTC_10K_44031_RESISTANCE_AT_25C) /
+			     NTC_10K_44031_BETA_VALUE) + (1 / NTC_10K_44031_ROOM_TEMP_IN_KELVIN))) - 273.15;
+	return temperature;
+#else
 	return thermistor::convert(resistance, coeff_A, coeff_B, coeff_C);
+#endif
 }