Lines Matching +full:non +full:- +full:negative
1 # SPDX-License-Identifier: (GPL-2.0 OR BSD-2-Clause)
2 ---
3 $id: http://devicetree.org/schemas/hwmon/ntc-thermistor.yaml#
4 $schema: http://devicetree.org/meta-schemas/core.yaml#
9 - Naveen Krishna Chatradhi <ch.naveen@samsung.com>
10 - Linus Walleij <linus.walleij@linaro.org>
13 Thermistors with negative temperature coefficient (NTC) are resistors that
14 vary in resistance in an often non-linear way in relation to temperature.
15 The negative temperature coefficient means that the resistance decreases
17 temperature is non-linear, software drivers most often need to use a look
21 pull-up resistor or/and a pull-down resistor and a fixed voltage like this:
23 + e.g. 5V = pull-up voltage (puv)
25 +-+
27 | | Pull-up resistor
29 +-+
30 |-------------------------o
31 +-+ | ^
37 +-+ |
38 |-------------------------o
39 +-+ ^
41 | | Pull-down resistor | Measured voltage (mv)
43 +-+ |
50 the cases when either pull-up or pull-down resistance is zero.
52 If the pull-up resistance is 0 one end of the thermistor is connected to the
53 positive voltage and we get the thermistor on top of a pull-down resistor
54 and we take the measure between the thermistor and the pull-down resistor.
56 Conversely if the pull-down resistance is zero, one end of the thermistor is
57 connected to ground and we get the thermistor under the pull-up resistor
58 and we take the measure between the pull-up resistor and the thermistor.
60 We can use both pull-up and pull-down resistors at the same time, and then
70 - const: epcos,b57330v2103
71 - const: epcos,b57891s0103
72 - const: murata,ncp15wb473
73 - const: murata,ncp18wb473
74 - const: murata,ncp21wb473
75 - const: murata,ncp03wb473
76 - const: murata,ncp15wl333
77 - const: murata,ncp03wf104
78 - const: murata,ncp15xh103
79 - const: samsung,1404-001221
81 - const: ntc,ncp15wb473
83 - const: ntc,ncp18wb473
85 - const: ntc,ncp21wb473
87 - const: ntc,ncp03wb473
89 - const: ntc,ncp15wl333
92 "#thermal-sensor-cells":
96 pullup-uv:
98 description: Pull-up voltage in micro volts. Must always be specified.
100 pullup-ohm:
102 description: Pull-up resistance in ohms. Must always be specified, even
105 pulldown-ohm:
107 description: Pull-down resistance in ohms. Must always be specified, even
110 connected-positive:
113 a pull-up and/or a pull-down resistor. See the description above for
115 to be connected-ground, which usually means a pull-down resistance of
119 io-channels:
125 - compatible
126 - pullup-uv
127 - pullup-ohm
128 - pulldown-ohm
129 - io-channels
134 - |
137 io-channels = <&gpadc 0x06>;
138 pullup-uv = <1800000>;
139 pullup-ohm = <220000>;
140 pulldown-ohm = <0>;
141 #thermal-sensor-cells = <0>;