Diff: ptc_ky81_110.cpp

Revision:

1:f65f6fadda5d

Child:

2:bcfa5a2f21c9

--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/ptc_ky81_110.cpp	Mon Feb 22 05:08:54 2021 +0000
@@ -0,0 +1,80 @@
+/*!
+ *****************************************************************************
+  @file:  ptc_ky81_110.cpp
+
+  @brief: This file contains functionality for PTC KY81/110 model
+
+  @details:
+ -----------------------------------------------------------------------------
+ Copyright (c) 2021 Analog Devices, Inc.  All rights reserved.
+
+ This software is proprietary to Analog Devices, Inc. and its licensors.
+ By using this software you agree to the terms of the associated
+ Analog Devices Software License Agreement.
+
+*****************************************************************************/
+
+#include "thermistor.h"
+#include "ptc_ky81_110.h"
+
+#ifdef DEFINE_LOOKUP_TABLES
+/* PTC look-up table. Values are resistance in ohm for temperature
+ * range from -10 to 80C with +/-1C tolerance.
+ * @note This table is derived based on the look-up table specified
+ *		 in the datasheet of KY81/110 part. The linear interpolation
+ *		 has been used to obtain 1C step size.
+**/
+const uint32_t ptc_ky81_110::lut[] = {
+	747, 753, 760, 767, 774, 781, 787, 794, 801, 808, 815, 822, 829, 836,
+	843, 850, 857, 864, 871, 878, 886, 893, 901, 908, 916, 923, 931, 938,
+	946, 953, 961, 968, 976, 984, 992, 1000, 1008, 1016, 1024, 1032, 1040,
+	1048, 1056, 1064, 1072, 1081, 1089, 1097, 1105, 1113, 1122, 1130, 1139,
+	1148, 1156, 1165, 1174, 1182, 1191, 1200, 1209, 1218, 1227, 1236, 1245,
+	1254, 1263, 1272, 1281, 1290, 1299, 1308, 1317, 1326, 1336, 1345, 1354,
+	1364, 1373, 1382, 1392, 1401, 1411, 1421, 1431, 1441, 1450, 1460, 1470,
+	1480, 1490
+};
+#endif
+
+
+/*!
+ * @brief	This is a constructor for ptc_ky81_110 class
+ * @return	none
+ */
+ptc_ky81_110::ptc_ky81_110()
+{
+	temperature_coeff = 0.79;		/* Temperature coefficient for KY81/110 */
+
+#ifdef DEFINE_LOOKUP_TABLES
+	ptc_ky81_110::lut_offset = -10; /* Min temperature obtained through LUT */
+	ptc_ky81_110::lut_size = 90;	/* Temperature range defined in LUT
+									   [lut_offset : lut_size - lut_offset] */
+#endif
+}
+
+
+/*!
+ * @brief	Convert the thermistor resistance into equivalent temperature
+ * @param	resistance[in] - thermistor resistance
+ * @return	Thermistor temperature value
+ * @note	Resistance at room temperature is 1000 ohms (1K)
+ */
+float ptc_ky81_110::convert(const float resistance)
+{
+	return (((resistance - 1000) / 1000) * (100.0 / temperature_coeff)) + 25.0;
+}
+
+
+#ifdef DEFINE_LOOKUP_TABLES
+/*!
+ * @brief	Convert the thermistor resistance into equivalent temperature using
+ *			lookup table for KY81/110 NTC
+ * @param	resistance[in] - thermistor resistance
+ * @return	Thermistor temperature value
+ */
+float ptc_ky81_110::lookup(const float resistance)
+{
+	return thermistor::lookup(lut, resistance, lut_size, lut_offset);
+}
+#endif
+