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Old Jun 04, 2013, 10:32 AM
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The definite Guide to Power connectors, charging, and other power related questions

Mobius ActionCam

This guide is designed as a reference for the most common power-related questions and is thus fairly long. However, I hope you will find the answer to your question.

This post will be kept up to date.

Description
The Mobius ActionCam will run for about 80 minutes from a new fully charged 520mAh internal battery or for over 2 hours with the new 820mAh internal battery. Recording in cold weather will drastically reduce the recording time.
Since you can't physically turn the battery off, the battery will always drain in order to keep the clock running. I don't know how long it will take to completely drain the battery, but I would expect a year, most probably much longer.

The camera can be configured either manually by editing an ASCII text file or much more conveniently by using the mSetup program (see post #6).
Recording without sound will give slightly longer recording times. Likewise, recording with a low video data rate will slightly increase the recording times. The recording indicator (flashing LED while recording) has no noticeable effect on the recording times. The recording indicator can be turned on or off in the configuration utility / text file.
The camera always records "clips" of a given length. The clip lengths can be set in the configuration utility / text file (see above). If the "Max." value is set, the camera will record clips with a length of 4GB. After the camera has written a clip, it will automatically create and record a new clip. This procedure will be repeated until the battery reaches a given threshold (runs out of power) or the flash card is full. If the camera is configured for loop recording, the oldest clips will be overwritten and recording will continue until there is no more internal or external power. There will be a 1 second overlap of two consecutive clips. The camera supports SD/SDXC cards formatted in FAT32 or exFAT and supports cards up to at least 128GB, most likely up to the exFAT limit of 512 terabytes.

Internal battery
The internal battery is a lithium polymer cell (LIPO), which, when fully charged, has a capacity of 4.2V. The camera will turn off when the battery voltage reaches approx. 3.5V.
The battery is user replaceable and comes with a tiny 2-pin connector. Since a connected external USB power supply will always supply more power than the camera functions require, the internal LIPO will be charged even when using the camera in Disk Mode, Webcam Mode, or Recording.
Battery protection circuitry is built into the camera. For this reason you should not replace the internal battery with another type of battery (for example Li-Ion). It is, however, possible to connect an external LIPO 1S battery in place of the internal battery but it should be recharged using an external charger.
The built-in charger circuitry is designed to charge a 520mAh LiPo (603030). Newer cameras are designed to use an 820mAh LiPo (803132). Newer models are date-stamped with 2014-08-19 (or later) on the circuit board under the lens module cable. A depleted battery will take between 2 and 2.5 hours to fully charge with the camera turned off. The green LED will be extinguished when the battery is fully charged. It is safe to assume the battery is fully charged after 2.5 hours even if the green LED is still lit. The latest 820mAh batteries will fit into older cameras but will take much longer to fully charge.
You should never connect a second battery in series. Doing so will destroy your camera because the voltage is the sum of all the battery volts.
You should also not connect batteries in parallel unless they have been properly "balanced" by an external charger. If the cells are not at the same state of charge, the higher charged cell(s) will try to charge the lower charged cell(s) with no current limit. This could damage the cells and cause dangerous overheating of cells and wiring.
If you replace the internal battery with another source of power (battery, charger, etc.) the supplied voltage must not exceed 4.2V (5V is not permitted on the battery connector). Doing so may initially work but will over-stress other components and will most likely lead to premature camera failure. If you must connect a 5V supply to the battery connector, then use a small diode (e.g. 1N4001) wired in series in the positive line. This will drop the voltage by about 0.7V. You obviously have to connect the diode correctly or no current will flow!

Using an external single cell LIPO in place of the internal battery
Some users my prefer to use a larger single cell LIPO in place of the standard one. This is possible so long the internal battery is never connected at the same time. You should note, however, that charging a larger battery using the Mobius' charging circuitry will take a very long time. Also remember that every time you disconnect the battery from the board, even very, very briefly, the internal clock will be reset.

The USB cable
A standard mini USB cable has +5V connected to pin #1 of the camera's USB socket and -V (ground / earth) connected to pin #5 of the camera's mini USB socket.
On a standard mini USB plug the two center wires (Pin #2 and Pin #3) are the data lines and are only used when the camera is connected to a computer. They are not used when the camera is connected to an external power source such as car battery charger, external wall charger (mains charger), external USB power pack etc.
The camera "tests" the data lines as well as pin #4 to determine the connection type.
The camera can be operated normally using external USB power with the internal battery disconnected.
Pin #4, which is sometimes called Pin x, will switch the camera into AV-out mode (TV-Out) when connected to ground. When in AV-out mode, pin #2 carries the composite video-out signal. In addition, pin #3 carries the audio-out signal when the camera is in playback mode. When switched into AV-out mode by connecting pin #4 to ground (see above), there will be a composite video signal present on pin #2 as soon as the camera is turned on. Auto-power-off will automatically be disabled.
A word of caution for #11 owners: If you use the #11 "special" cable on your Mobius ActionCam you will destroy it!

The table below shows all the possible cable connections. In practice you will only need max. 2 different cables. The Mobius is normally sold with a universal cable harness.





Charging only, using a standard USB charger
When charging, the green LED will be on.
When fully charged, the green LED will be off.
The camera can be charged by any standard *USB source. This includes:
• USB mains adapters (wall adapters), e.g. mobile phone chargers, navigation chargers, USB chargers, etc.
• USB standard car battery chargers.
• USB backup batteries designed to power/charge mobile phones, navigation devices, etc.
• USB computer connection.
►Only use quality chargers capable of supplying 1000mA (1A) and a stable voltage of at least 5V. Low quality chargers may not be able to supply enough current and can lead to premature battery failure or, in the worst case, even destroy the camera.
* Not all USB devices can supply enough current to charge the internal battery. Most mobile phones etc. will NOT be able to charge the battery.

Charging only, using a PC
When connected to a PC with an SD card inserted, the camera will be connected as an external drive. The battery will be charged.
If you only want to charge the battery, briefly press the Power button to turn the camera off. It is advisable to "safely disconnect" the drive before doing this (method varies depending on your operating system).

Simultaneous Charging and Recording using standard USB cables/adapters
The cable can be connected to any USB power source as long as the power source can supply 5 Volts under load. Note: Some USB hubs do not supply enough current. If the USB hub can't supply a nominal voltage under load, the camera will run on the internal battery which will be flat before the battery has a chance to charge!
• When powering from the computer, the recording must be started before connecting the USB.
• When powering from an external USB power source, the cable can be connected at any time, e.g. when the camera is turned off, before starting the recording, during the recording.
►Only use quality chargers capable of supplying 1000mA (1A) and a stable voltage of at least 5V. Low quality chargers may not be able to supply enough current and can lead to premature battery failure or, in the worst case, even destroy the camera.
►The battery or charger must only use the +5V and Ground wires. Some batteries/chargers also use the data wires. In this case the camera will think the power source is a computer - i.e. you will never be able to record more than one clip! Cut the two data wires (usually white and blue or green) and the battery/charger will work as expected.

Using external power it is possible to record about 4.5 hours of continuous video (many clips created automatically) using a 32GB micro SD card or about 8.5 hours using a 64GB micro SDXC card or about 17 hours using a 128GB micro SDXC card. These are average values using standard settings with 1080p30.

I highly recommend the Just Mobile Gum Pro PP-08, but any other USB high power external battery power packs will also work.

Technical
• When the camera is turned off, the RTC and processor draw about 15μA.
• When the camera is turned on, but in standby mode, the camera consumes about 300mA.
• When the camera is recording, the camera draws between 350mA and 400mA.
• In order to protect the battery, the camera will stop recording and turn off when the voltage falls below approx. 3.5V.

Haku made the following measurements in post #1502:
No battery connected
• Standby mode: 225mA @ 4.97v
• Standby mode with AV-Out enabled: 265mA @ 4.97v
• Recording 1080p: 305mA @ 4.97v
• Recording 1080p with AV-OUT enabled: 330mA @ 4.96v
Battery connected
• Battery being charged from flat, powered off: 186mA @ 4.97v
• Battery being charged from flat, recording 1080p: average 505mA @ 4.95v

Using the camera with only external USB power (internal battery disconnected)
The camera can be used without a battery connected to the internal connector on the board. Remember that the RTC (Real Time Clock) will be reset every time the external USB power is removed.
• The camera requires an absolute minimum of 4.18V to operate correctly. This value may vary with the type of card used. I would think 4.3V would be a safer figure.
• It is possible to use a supercapacitor in place of the internal battery. This will keep the RTC running for up to 10 days. It is not possible to use the supercapacitor to power the camera. Installing a supercapacitor requires the camera to be powered by external USB power.

A word of WARNING
External power should be a nominal 5V. Fractionally higher voltages (such as from a fully charged 4 cell NiMH battery pack) can be tolerated without undue stress of the camera components
• The latest cameras (2014-08-19 or later) incorporate over-voltage protection and should protect the camera against excessive voltage up to 28V max. If the voltage exceeds 5V the battery will not charge. Reverse polarity or connecting incorrect USB pins will damage the board.

RC electric plane models - Warning
It is not recommended to plug the camera into a spare channel on the receiver. This may work, but it may also cause complete shutdown of the external electronics. If the voltage supplied to the camera's USB port is in excess of 5V (5%) there is also the risk of over stressing the camera's circuitry.
When recording, the camera draws as much power as a mini servo... and a bit higher when also outputting composite video for FPV. If the receiver is being powered by a separate battery, then the solution may work as long as the battery can handle the extra current. If the receiver is being powered by a linear BEC circuit on the motor ESC, adding the camera to that circuit may overload it and cause it to go into thermal shutdown, which in that case would mean total loss of control and a crash scenario!
If you must use a spare channel on the receiver, the complete electrical circuit needs to be taken into account and no components should become warmer than usual.

External USB battery packs
You cannot use a battery box with only 3 AAA / 3 AA batteries unless it incorporates step-up electronics to output 5V.
3 Batteries can only supply about 3.6V, but the camera requires a minimum of approx. 4.7V constant voltage. It will not charge or record when the voltage falls below approx. 4.3V.

Commercial external USB battery powered chargers
There are many different external USB battery power packs available. Mobius sellers may also stock them.
A word of warning. Some 'Intelligent' power packs have recently appeared on the market that shut down when the current draw drops below 50mA! Don't use these chargers - they will most likely not work correctly and may even cause damage to your camera. A power pack that automatically turns off defeats the whole idea of using external power!
The most reliable battery packs are those which don't need any cable adapters. A few examples follow.

This is a typical external USB battery pack which can be found on eBay for about $30.
It has enough power for the camera to record video to almost completely fill a 32GB card.


This one is expensive, but by far the best. Costs more than $45. Can also be found on eBay. A real power horse!
Note: The cable supplied will NOT work for charging and recording at the same time. You must make your own 2-wire USB cable or simply cut the two data wires.


Car Charger (optional)
The optional car charger converts 12V DC into 5V DC. The center pin is the +5V and one of the connectors on the side is Ground (Earth). Any standard USB cable can be used together with the car charger.
If the car charger electronics are used with or without the casing to power the camera from a different 12V power source (external 3S lipo packs, for example), then the circuit will work well, but is probably too large to be practical.
Any 12V - 15V DC sources which need to be converted to 5V must go thru the car charger electronics (or similar regulator). You must NEVER bypass these electronics or apply 12V directly to the camera - doing so will destroy the camera.


DIY 3S LiPo Voltage Converter
bouzx6r has posted a simple method of converting a cheap car battery charger (see above picture) into a 3S LiPo-to-5V voltage converter. His idea may not be as small and compact as commercially available devices, but it's most probably just as good or even better. Click here for the original link with pictures.
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Last edited by Isoprop; Dec 02, 2014 at 02:57 AM. Reason: Keeping post up-to-date
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