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{{AppliesToSBCLynx}}
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==Introduction==
SBC Lynx in powered by one rail whose voltage is in the 5 - 24V range(±5%). This supply voltage can be provided via:
*[[Connectors,_buttons_and_switches_(SBC_Lynx)|connector J35 or connector JP1]] in case it is used as standalone board
*[[Connectors,_buttons_and_switches_(SBC_Lynx)|connector J52]] in case it is used as an add-on for a carrier board.
|VIN_5_24V||n/a||Dependent on main power supply voltage
|-
|SNVS||TBDSee [[Supported_power_mode_transitions_(SBC_Lynx)#Tablet_mode|this section]].||
|}
PMIC is in turn powered by a 2A DC/DC converter that is enabled by SXUB_ENA signal, available on [[Connectors,_buttons_and_switches_(SBC_Lynx)#CPU_ONOFF_.2F_Power_Reset_connector_.28J50.29|J50 connector]]. This signal is connected to VIN through a 100 kOhm resistor and to ground through a 56 kOhm resistor. As such, if J50.2 is left floating, DC/DC regulator is enabled when VIN is applied. Nevertheless, SXUB_ENA can be driven by external circuitry to turn the regulator off, even if VIN is the range 5 - 24V.
Two of the supplies generated by PMIC are available to power external devices or add-on boards.
[2] AUX_5V is generated by a 600mA boost DC/DC converter. As this converter powers USB devices connected to J47 and J48 - if any - and DWM WiFi/Bluetooth module (if populated), maximum current available at connector J54 can not be provided.
==Power sequencing==
In case additional circuitry has to interfaced to processor's I/Os [1], '''proper power sequencing should be implemented''' in order to avoid back power phenomena. To do that, AUX_3.3V should be used:
* additional circuitry can be powered by AUX_3.3V directly
*AUX_3.3V can be used as enable signal to power-up this circuitry.
Either way, this ensures additional circuitry power-on sequence is compliant with processors requirements.
[1] For instance by the use of add-on boards interfaced to [[Connectors,_buttons_and_switches_(SBC_Lynx)#Mezzanine_board_connectors_.28J53.2FJ54.29|mezzanine]] or [[Connectors,_buttons_and_switches_(SBC_Lynx)#One-piece_interfaces_.28J45_.2F_J52.29|one-piece]] connectors.
