1 # SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause)
2 %YAML 1.2
3 ---
4 $id: http://devicetree.org/schemas/iio/temperature/adi,ltc2983.yaml#
5 $schema: http://devicetree.org/meta-schemas/core.yaml#
6
7 title: Analog Devices LTC2983, LTC2986, LTM2985 Multi-sensor Temperature system
8
9 maintainers:
10 - Nuno Sá <nuno.sa@analog.com>
11
12 description: |
13 Analog Devices LTC2983, LTC2984, LTC2986, LTM2985 Multi-Sensor Digital
14 Temperature Measurement Systems
15
16 https://www.analog.com/media/en/technical-documentation/data-sheets/2983fc.pdf
17 https://www.analog.com/media/en/technical-documentation/data-sheets/2984fb.pdf
18 https://www.analog.com/media/en/technical-documentation/data-sheets/29861fa.pdf
19 https://www.analog.com/media/en/technical-documentation/data-sheets/ltm2985.pdf
20
21 $defs:
22 sensor-node:
23 type: object
24 description: Sensor node common constraints
25
26 properties:
27 reg:
28 description:
29 Channel number. Connects the sensor to the channel with this number
30 of the device.
31 minimum: 1
32 maximum: 20
33
34 adi,sensor-type:
35 description: Type of sensor connected to the device.
36 $ref: /schemas/types.yaml#/definitions/uint32
37
38 required:
39 - reg
40 - adi,sensor-type
41
42
43 properties:
44 compatible:
45 oneOf:
46 - enum:
47 - adi,ltc2983
48 - adi,ltc2986
49 - adi,ltm2985
50 - items:
51 - const: adi,ltc2984
52 - const: adi,ltc2983
53
54 reg:
55 maxItems: 1
56
57 interrupts:
58 maxItems: 1
59
60 vdd-supply: true
61
62 adi,mux-delay-config-us:
63 description: |
64 Extra delay prior to each conversion, in addition to the internal 1ms
65 delay, for the multiplexer to switch input configurations and
66 excitation values.
67
68 This property is supposed to be in microseconds, but to maintain
69 compatibility, this value will be multiplied by 100 before usage.
70 maximum: 255
71 default: 0
72
73 adi,filter-notch-freq:
74 description:
75 Notch frequency of the digital filter.
76 0 - 50/60Hz rejection
77 1 - 60Hz rejection
78 2 - 50Hz rejection
79 $ref: /schemas/types.yaml#/definitions/uint32
80 minimum: 0
81 maximum: 2
82 default: 0
83
84 '#address-cells':
85 const: 1
86
87 '#size-cells':
88 const: 0
89
90 patternProperties:
91 "^thermocouple@":
92 $ref: '#/$defs/sensor-node'
93 unevaluatedProperties: false
94
95 description: Thermocouple sensor.
96
97 properties:
98 adi,sensor-type:
99 description: |
100 1 - Type J Thermocouple
101 2 - Type K Thermocouple
102 3 - Type E Thermocouple
103 4 - Type N Thermocouple
104 5 - Type R Thermocouple
105 6 - Type S Thermocouple
106 7 - Type T Thermocouple
107 8 - Type B Thermocouple
108 9 - Custom Thermocouple
109 $ref: /schemas/types.yaml#/definitions/uint32
110 minimum: 1
111 maximum: 9
112
113 adi,single-ended:
114 description: Whether the sensor is single-ended.
115 type: boolean
116
117 adi,sensor-oc-current-microamp:
118 description: Pulsed current value applied during open-circuit detect.
119 enum: [10, 100, 500, 1000]
120 default: 10
121
122 adi,cold-junction-handle:
123 description:
124 Sensor responsible for measuring the thermocouple cold junction
125 temperature.
126 $ref: /schemas/types.yaml#/definitions/phandle
127
128 adi,custom-thermocouple:
129 description:
130 Used for digitizing custom thermocouples.
131 See Page 59 of the datasheet.
132 $ref: /schemas/types.yaml#/definitions/int64-matrix
133 minItems: 3
134 maxItems: 64
135 items:
136 items:
137 - description: Voltage point in nV, signed.
138 - description: Temperature point in uK.
139
140 allOf:
141 - if:
142 properties:
143 adi,sensor-type:
144 const: 9
145 then:
146 required:
147 - adi,custom-thermocouple
148
149 "^diode@":
150 $ref: '#/$defs/sensor-node'
151 unevaluatedProperties: false
152
153 description: Diode sensor.
154
155 properties:
156 adi,sensor-type:
157 description: Sensor type for diodes.
158 $ref: /schemas/types.yaml#/definitions/uint32
159 const: 28
160
161 adi,single-ended:
162 description: Whether the sensor is single-ended.
163 type: boolean
164
165 adi,three-conversion-cycles:
166 description:
167 Whether to use three conversion cycles to remove parasitic
168 resistance between the device and the diode.
169 type: boolean
170
171 adi,average-on:
172 description:
173 Whether to use a running average of the diode temperature
174 reading to reduce the noise when the diode is used as a cold
175 junction temperature element on an isothermal block where
176 temperatures change slowly.
177 type: boolean
178
179 adi,excitation-current-microamp:
180 description:
181 Magnitude of the 1l excitation current applied to the diode.
182 4l excitation current will be 4 times this value, and 8l
183 excitation current will be 8 times value.
184 enum: [10, 20, 40, 80]
185 default: 10
186
187 adi,ideal-factor-value:
188 description:
189 Diode ideality factor.
190 Set this property to 1000000 times the real value.
191 $ref: /schemas/types.yaml#/definitions/uint32
192 default: 0
193
194 "^rtd@":
195 $ref: '#/$defs/sensor-node'
196 unevaluatedProperties: false
197 description: RTD sensor.
198
199 properties:
200 reg:
201 minimum: 2
202 maximum: 20
203
204 adi,sensor-type:
205 description: |
206 10 - RTD PT-10
207 11 - RTD PT-50
208 12 - RTD PT-100
209 13 - RTD PT-200
210 14 - RTD PT-500
211 15 - RTD PT-1000
212 16 - RTD PT-1000 (0.00375)
213 17 - RTD NI-120
214 18 - RTD Custom
215 $ref: /schemas/types.yaml#/definitions/uint32
216 minimum: 10
217 maximum: 18
218
219 adi,rsense-handle:
220 description: Associated sense resistor sensor.
221 $ref: /schemas/types.yaml#/definitions/phandle
222
223 adi,number-of-wires:
224 description:
225 Number of wires used by the RTD.
226 5 means 4 wires with Kelvin sense resistor.
227 $ref: /schemas/types.yaml#/definitions/uint32
228 enum: [2, 3, 4, 5]
229 default: 2
230
231 adi,rsense-share:
232 description:
233 Whether to enable sense resistor sharing, where one sense
234 resistor is used by multiple sensors.
235 type: boolean
236
237 adi,excitation-current-microamp:
238 description: Excitation current applied to the RTD.
239 enum: [5, 10, 25, 50, 100, 250, 500, 1000]
240 default: 5
241
242 adi,rtd-curve:
243 description: |
244 RTD curve and the corresponding Callendar-VanDusen constants.
245 0 - European
246 1 - American
247 2 - Japanese
248 3 - ITS-90
249 $ref: /schemas/types.yaml#/definitions/uint32
250 minimum: 0
251 maximum: 3
252 default: 0
253
254 adi,custom-rtd:
255 description:
256 Used for digitizing custom RTDs.
257 See Page 62 of the datasheet.
258 $ref: /schemas/types.yaml#/definitions/uint64-matrix
259 minItems: 3
260 maxItems: 64
261 items:
262 items:
263 - description: Resistance point in uOhms.
264 - description: Temperature point in uK.
265
266 required:
267 - adi,rsense-handle
268
269 allOf:
270 - if:
271 properties:
272 adi,number-of-wires:
273 const: 4
274 then:
275 properties:
276 adi,current-rotate:
277 description:
278 Whether to enable excitation current rotation to automatically
279 remove parasitic thermocouple effects.
280 type: boolean
281
282 dependencies:
283 adi,current-rotate: [ "adi,rsense-share" ]
284
285 - if:
286 properties:
287 adi,sensor-type:
288 const: 18
289 then:
290 required:
291 - adi,custom-rtd
292
293 "^thermistor@":
294 $ref: '#/$defs/sensor-node'
295 unevaluatedProperties: false
296 description: Thermistor sensor.
297
298 properties:
299 adi,sensor-type:
300 description:
301 19 - Thermistor 44004/44033 2.252kohm at 25°C
302 20 - Thermistor 44005/44030 3kohm at 25°C
303 21 - Thermistor 44007/44034 5kohm at 25°C
304 22 - Thermistor 44006/44031 10kohm at 25°C
305 23 - Thermistor 44008/44032 30kohm at 25°C
306 24 - Thermistor YSI 400 2.252kohm at 25°C
307 25 - Thermistor Spectrum 1003k 1kohm
308 26 - Thermistor Custom Steinhart-Hart
309 27 - Custom Thermistor
310 $ref: /schemas/types.yaml#/definitions/uint32
311 minimum: 19
312 maximum: 27
313
314 adi,rsense-handle:
315 description: Associated sense resistor sensor.
316 $ref: /schemas/types.yaml#/definitions/phandle
317
318 adi,single-ended:
319 description: Whether the sensor is single-ended.
320 type: boolean
321
322 adi,rsense-share:
323 description:
324 Whether to enable sense resistor sharing, where one sense
325 resistor is used by multiple sensors.
326 type: boolean
327
328 adi,current-rotate:
329 description:
330 Whether to enable excitation current rotation to automatically
331 remove parasitic thermocouple effects.
332 type: boolean
333
334 adi,excitation-current-nanoamp:
335 description:
336 Excitation current applied to the thermistor.
337 0 sets the sensor in auto-range mode.
338 enum: [0, 250, 500, 1000, 5000, 10000, 25000, 50000, 100000, 250000,
339 500000, 1000000]
340 default: 0
341
342 adi,custom-thermistor:
343 description:
344 Used for digitizing custom thermistors.
345 See Page 65 of the datasheet.
346 $ref: /schemas/types.yaml#/definitions/uint64-matrix
347 minItems: 3
348 maxItems: 64
349 items:
350 items:
351 - description: Resistance point in uOhms.
352 - description: Temperature point in uK.
353
354 adi,custom-steinhart:
355 description:
356 Steinhart-Hart coefficients in raw format, used for digitizing
357 custom thermistors.
358 See Page 68 of the datasheet.
359 $ref: /schemas/types.yaml#/definitions/uint32-array
360 minItems: 6
361 maxItems: 6
362
363 required:
364 - adi,rsense-handle
365
366 dependencies:
367 adi,current-rotate: [ "adi,rsense-share" ]
368
369 allOf:
370 - if:
371 properties:
372 adi,sensor-type:
373 const: 26
374 then:
375 properties:
376 adi,excitation-current-nanoamp:
377 enum: [250, 500, 1000, 5000, 10000, 25000, 50000, 100000,
378 250000, 500000, 1000000]
379 default: 1000
380 required:
381 - adi,custom-steinhart
382 - if:
383 properties:
384 adi,sensor-type:
385 const: 27
386 then:
387 properties:
388 adi,excitation-current-nanoamp:
389 enum: [250, 500, 1000, 5000, 10000, 25000, 50000, 100000,
390 250000, 500000, 1000000]
391 default: 1000
392 required:
393 - adi,custom-thermistor
394
395 "^adc@":
396 $ref: '#/$defs/sensor-node'
397 unevaluatedProperties: false
398 description: Direct ADC sensor.
399
400 properties:
401 adi,sensor-type:
402 description: Sensor type for direct ADC sensors.
403 $ref: /schemas/types.yaml#/definitions/uint32
404 const: 30
405
406 adi,single-ended:
407 description: Whether the sensor is single-ended.
408 type: boolean
409
410 "^temp@":
411 $ref: '#/$defs/sensor-node'
412 unevaluatedProperties: false
413 description: Active analog temperature sensor.
414
415 properties:
416 adi,sensor-type:
417 description: Sensor type for active analog temperature sensors.
418 $ref: /schemas/types.yaml#/definitions/uint32
419 const: 31
420
421 adi,single-ended:
422 description: Whether the sensor is single-ended.
423 type: boolean
424
425 adi,custom-temp:
426 description:
427 Used for digitizing active analog temperature sensors.
428 See Page 67 of the LTM2985 datasheet.
429 $ref: /schemas/types.yaml#/definitions/uint64-matrix
430 minItems: 3
431 maxItems: 64
432 items:
433 items:
434 - description: Voltage point in nV, signed.
435 - description: Temperature point in uK.
436
437 required:
438 - adi,custom-temp
439
440 "^rsense@":
441 $ref: '#/$defs/sensor-node'
442 unevaluatedProperties: false
443 description: Sense resistor sensor.
444
445 properties:
446 reg:
447 minimum: 2
448 maximum: 20
449
450 adi,sensor-type:
451 description: Sensor type sense resistor sensors.
452 $ref: /schemas/types.yaml#/definitions/uint32
453 const: 29
454
455 adi,rsense-val-milli-ohms:
456 description: Value of the sense resistor.
457
458 required:
459 - adi,rsense-val-milli-ohms
460
461 required:
462 - compatible
463 - reg
464 - interrupts
465 - vdd-supply
466
467 additionalProperties: false
468
469 allOf:
470 - if:
471 properties:
472 compatible:
473 contains:
474 enum:
475 - adi,ltc2983
476 - adi,ltc2984
477 then:
478 patternProperties:
479 "^temp@": false
480
481 examples:
482 - |
483 #include <dt-bindings/interrupt-controller/irq.h>
484 spi {
485 #address-cells = <1>;
486 #size-cells = <0>;
487
488 temperature-sensor@0 {
489 compatible = "adi,ltc2983";
490 reg = <0>;
491
492 #address-cells = <1>;
493 #size-cells = <0>;
494
495 vdd-supply = <&supply>;
496 interrupts = <20 IRQ_TYPE_EDGE_RISING>;
497 interrupt-parent = <&gpio>;
498
499 thermocouple@18 {
500 reg = <18>;
501 adi,sensor-type = <8>; //Type B
502 adi,sensor-oc-current-microamp = <10>;
503 adi,cold-junction-handle = <&diode5>;
504 };
505
506 diode5: diode@5 {
507 reg = <5>;
508 adi,sensor-type = <28>;
509 };
510
511 rsense2: rsense@2 {
512 reg = <2>;
513 adi,sensor-type = <29>;
514 adi,rsense-val-milli-ohms = <1200000>; //1.2Kohms
515 };
516
517 rtd@14 {
518 reg = <14>;
519 adi,sensor-type = <15>; //PT1000
520 /*2-wire, internal gnd, no current rotation*/
521 adi,number-of-wires = <2>;
522 adi,rsense-share;
523 adi,excitation-current-microamp = <500>;
524 adi,rsense-handle = <&rsense2>;
525 };
526
527 adc@10 {
528 reg = <10>;
529 adi,sensor-type = <30>;
530 adi,single-ended;
531 };
532
533 thermistor@12 {
534 reg = <12>;
535 adi,sensor-type = <26>; //Steinhart
536 adi,rsense-handle = <&rsense2>;
537 adi,custom-steinhart = <0x00f371ec 0x12345678
538 0x2c0f8733 0x10018c66 0xa0feaccd
539 0x90021d99>; //6 entries
540 };
541
542 thermocouple@20 {
543 reg = <20>;
544 adi,sensor-type = <9>; //custom thermocouple
545 adi,single-ended;
546 adi,custom-thermocouple =
547 /bits/ 64 <(-50220000) 0>,
548 /bits/ 64 <(-30200000) 99100000>,
549 /bits/ 64 <(-5300000) 135400000>,
550 /bits/ 64 <0 273150000>,
551 /bits/ 64 <40200000 361200000>,
552 /bits/ 64 <55300000 522100000>,
553 /bits/ 64 <88300000 720300000>,
554 /bits/ 64 <132200000 811200000>,
555 /bits/ 64 <188700000 922500000>,
556 /bits/ 64 <460400000 1000000000>; //10 pairs
557 };
558 };
559 };
560 ...
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