Juice4halt

the batteryless Micro-UPS for Raspberry Pi

and other 5V Single Board Computers 


Features

  • no batteries - the Juice4halt modules use supercapacitors instead of batteries

  • no maintenance - no batteries means no maintenance, supercapacitors are maintenance-free
  • long life - long supercapacitor lifetime means long life for the whole device
  • industrial temperature range - almost every battery type has problems when operated at -40°C or +60°C. Thanks to supercapacitors this not a problem anymore
  • safety and reliability - supercapacitors can be fully discharged for transport, no danger of fire or explosion
  • environmentally friendly - no hazardous materials for disposal, supercapacitors contain non-toxic materials

 


Juice4halt - the reliable solution for special environments...

  • when a regular maintenance of batteries is a problem due to bad accessibility (remote sites, pole masts, tunnels)
  • when a wide temperature range is required (outdoor or industrial applications)
  • when restrictions due to fire or explosion danger is an issue (aircraft transportation)
     


We don`t recommend using J4H...

  • for long backup times

  • when looking for the lowest cost UPS solution
  • where maintenance (e.g. battery change) is not a problem
  • when the ambient temperatures will not fall far below the freezing point
     

 

Performance 

  • designed for Raspberry Pi Models B+, 2, 3
  • 60 seconds backup time including a safe shutdown
  • 20 seconds protection against short-term power failure (no shutdown)
  • wide operating temperature range (-40°C to +85°C)
  • 5V input or 7...28V input
  • Improved supply reliability also for other peripherals attached to the 5V supply output

only for the RTC-485 model:

  • Real-Time Clock with long life Lithium Coin Battery power backup
  • RS-485 Interface
  • ON/OFF Push Button

For more precise performance information, please consult the datasheet

 

 

How does it work?

Block diagram
5V model

(J4H-5V-USB)


block_diagram_5V_20171130
Block diagram
HV model

(J4H-HV-TRM)

 

block_diagram_HV_20171130
Block dagram
RTC-485 model

(J4H-HV-TRM-RTC-485)

 

block_diagram_RTC-485_20171130

The Juice4halt 5V module is a supercapacitor-based energy storage. It contains a bidirectional step-up/step-down converter working as the interface between the stable 5V supply rail and the supercapacitor. During charging the converter works in step-down mode and transports energy from the external power supply to the supercapacitor. In case of a power failure, the load device (Raspberry Pi or another SBC) is supplied from the supercapacitor via DC/DC converter working in step-up mode.

The Juice4halt HV module is a supercapacitor-based energy storage. It contains two independent DC/DC converters.

The first one is a bidirectional step-up/step-down converter working as the interface between the stable 5V supply rail and the supercapacitor. During charging the converter works in step-down mode and transports energy from the external power supply to the supercapacitor. In case of a power failure, the load device (Raspberry Pi or another SBC) is supplied from the supercapacitor via DC/DC converter working in step-up mode.

The second DC/DC converter is a Front-end step-down converter. The only function is converting a high input voltage down to 5.1V for the 5V rail.

The Juice4halt RTC-485 module is a supercapacitor-based energy storage. It contains two independent DC/DC converters.

The first one is a bidirectional step-up/step-down converter working as the interface between the stable 5V supply rail and the supercapacitor. During charging the converter works in step-down mode and transports energy from the external power supply to the supercapacitor. In case of a power failure, the load device (Raspberry Pi or another SBC) is supplied from the supercapacitor via DC/DC converter working in step-up mode.

The second DC/DC converter is a Front-end step-down converter. The only function is converting a high input voltage down to 5.1V for the 5V rail.

The RS-485 Interface is accessed via a 3-pole screw terminal at the inner side edge of the PCB. The RS-485 Interface is transformed and connected to the UART interface of the Raspberry Pi.

The Real-Time Clock uses a lithium coin battery for power backup when the Raspberry Pi is powered off. The battery holder is situated on the top side of the PCB.

A push-button is used as a Power ON/OFF switch, and perfectly fits into the shutdown and booting scenarios, leading to a function very typical for all laptop-power-on/off buttons or for ATX power supply soft start buttons.