LAVA Computer MFG STS Product Family User Manual – A01
2 Vulcan St. Toronto, ON Tel: +1 416 674-5942 www.lavalink.com
13 of 20
Canada, M9W 1L2 Fax: +1 416 674-8262 Toll Free (US & Canada): 800 241-5282
“Micro-B USB 5V Power Input”
The “5V Power Input” is a Micro USB-B Receptacle on STS** products without Power over Ethernet.
The 5V Power Input provides power for the STS** product, the tablet, and for attached USB accessories.
The STS** Product will not function if power has not been applied to the 5V Power Input. The STS**
products do not draw power from the tablet.
A standard USB 5V DC Power Supply is attached to the 5V Power Input. The supply need not be a Direct
Charge Port (DCP) compliant device. A standard USB power supply is rated at 5 volts nominal, with a 5.25
volts maximum. The typical current rating is 2 amperes for a tablet with at least a 10-inch screen. A typical
USB Power supply is rated at 10 watts (2 amperes at 5 volts DC).
The 5V Power Input on the STS** products can be used with external USB Battery Packs. This ability can
be useful some kiosk configurations. The USB Battery Pack must be physically removed for recharging.
The cable length between the Power Supply and the STS** Product must be as short as possible. The cable
has power loss proportional to the cable length and wire thickness. The voltage present at the STS**
receptacle will be lower than the supply output due to cable power loss. There is power loss in the cable
which connects the STS** to the tablet. If the voltage at the tablet is too low, the tablet will not charge.
The minimum USB voltage is 4.75 volts for USB accessories operating at a full unit load, which requires
the 5V Power Input to be above 4.75 volts to account for cable power loss.
The models with the 5V Power Input include the STS, STS-3U, STS-E, STS-2UE, and STS-2UE+.
“Micro-B USB Aux 5V Input”
The ‘Aux 5V Input” is a Micro USB-B Receptacle on STS** products with PoE capability.
This input
is only
used for system testing when PoE power
is not
present. The STS** Product will be fully
functional including the 10/100 Ethernet, when this power input is used.
A standard USB 5V DC Power Supply is attached to the Aux 5V Input. A standard USB power supply is
rated at 5 volts nominal, with a 5.25 volts maximum. The typical current rating is 2 amperes for a tablet
with at least a 10-inch screen. A typical USB Power supply is rated at 10 watts (2 amperes at 5 volts DC).
The STS** Product does not function if power has not been applied either via PoE or the Aux 5V Input.
The PoE models include the STS-PE, STS-P2UE, and STS-P2UE+ products.
“USB-A” receptacles
A majority of the STS** products have one or more USB 2.0 ports with a standard A-type receptacle. Each
receptacle allows a USB Accessory to be accessed by the tablet. Each receptacle provides power to each
USB accessory.
