xref: /freebsd/sys/contrib/device-tree/Bindings/regulator/ltc3589.txt (revision 02e9120893770924227138ba49df1edb3896112a)
1Linear Technology LTC3589, LTC3589-1, and LTC3589-2 8-output regulators
2
3Required properties:
4- compatible: "lltc,ltc3589", "lltc,ltc3589-1" or "lltc,ltc3589-2"
5- reg: I2C slave address
6
7Required child node:
8- regulators: Contains eight regulator child nodes sw1, sw2, sw3, bb-out,
9  ldo1, ldo2, ldo3, and ldo4, specifying the initialization data as
10  documented in Documentation/devicetree/bindings/regulator/regulator.txt.
11
12Each regulator is defined using the standard binding for regulators. The
13nodes for sw1, sw2, sw3, bb-out, ldo1, and ldo2 additionally need to specify
14the resistor values of their external feedback voltage dividers:
15
16Required properties (not on ldo3, ldo4):
17- lltc,fb-voltage-divider: An array of two integers containing the resistor
18  values R1 and R2 of the feedback voltage divider in ohms.
19
20Regulators sw1, sw2, sw3, and ldo2 can regulate the feedback reference from
210.3625 V to 0.75 V in 12.5 mV steps. The output voltage thus ranges between
220.3625 * (1 + R1/R2) V and 0.75 * (1 + R1/R2) V. Regulators bb-out and ldo1
23have a fixed 0.8 V reference and thus output 0.8 * (1 + R1/R2) V. The ldo3
24regulator is fixed to 1.8 V on LTC3589 and to 2.8 V on LTC3589-1,2. The ldo4
25regulator can output between 1.8 V and 3.3 V on LTC3589 and between 1.2 V
26and 3.2 V on LTC3589-1,2 in four steps. The ldo1 standby regulator can not
27be disabled and thus should have the regulator-always-on property set.
28
29Example:
30
31	ltc3589: pmic@34 {
32		compatible = "lltc,ltc3589-1";
33		reg = <0x34>;
34
35		regulators {
36			sw1_reg: sw1 {
37				regulator-min-microvolt = <591930>;
38				regulator-max-microvolt = <1224671>;
39				lltc,fb-voltage-divider = <100000 158000>;
40				regulator-ramp-delay = <7000>;
41				regulator-boot-on;
42				regulator-always-on;
43			};
44
45			sw2_reg: sw2 {
46				regulator-min-microvolt = <704123>;
47				regulator-max-microvolt = <1456803>;
48				lltc,fb-voltage-divider = <180000 191000>;
49				regulator-ramp-delay = <7000>;
50				regulator-boot-on;
51				regulator-always-on;
52			};
53
54			sw3_reg: sw3 {
55				regulator-min-microvolt = <1341250>;
56				regulator-max-microvolt = <2775000>;
57				lltc,fb-voltage-divider = <270000 100000>;
58				regulator-ramp-delay = <7000>;
59				regulator-boot-on;
60				regulator-always-on;
61			};
62
63			bb_out_reg: bb-out {
64				regulator-min-microvolt = <3387341>;
65				regulator-max-microvolt = <3387341>;
66				lltc,fb-voltage-divider = <511000 158000>;
67				regulator-boot-on;
68				regulator-always-on;
69			};
70
71			ldo1_reg: ldo1 {
72				regulator-min-microvolt = <1306329>;
73				regulator-max-microvolt = <1306329>;
74				lltc,fb-voltage-divider = <100000 158000>;
75				regulator-boot-on;
76				regulator-always-on;
77			};
78
79			ldo2_reg: ldo2 {
80				regulator-min-microvolt = <704123>;
81				regulator-max-microvolt = <1456806>;
82				lltc,fb-voltage-divider = <180000 191000>;
83				regulator-ramp-delay = <7000>;
84				regulator-boot-on;
85				regulator-always-on;
86			};
87
88			ldo3_reg: ldo3 {
89				regulator-min-microvolt = <2800000>;
90				regulator-max-microvolt = <2800000>;
91				regulator-boot-on;
92			};
93
94			ldo4_reg: ldo4 {
95				regulator-min-microvolt = <1200000>;
96				regulator-max-microvolt = <3200000>;
97			};
98		};
99	};
100