Powering Teensy from 6V

I want to control 6 motors with a teensy 4.1 while having in externally powered. I was wondering if I could solder my 4xAA battery holder to the teensy and then wire the vin pin to a solderable breadboard where I would distribute power to the motors and drivers. I am just making sure I won't fry anything. I am using micro metal gearmotors (pololu item #1101) with encoders and I am using 3 adafruit TB6612fng for the drivers.
 
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You haven't said what Teensy it is, nor what batteries you intend to use.
Give us that information and we may be able to help you.
 
As you can see there are a number of chemistries used in Energiser batteries.
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Which are you using?
 
What current draw will the motors pull?
For Alkaline batteries you should work on a voltage of 1.2V per battery.
Will the motors work off 4.8V?
 
I think what @BriComp is trying to say is that with 4 AA batteries you may not have enough power to drive the motors as well as the Teensy. In addition 4 may insufficient (4.8v) to drive a 6v motor.

Typically, what I do in situations like this is get a batttery bank like an anker that can supply both 5v and 9v ( you can check on amazon). I use the 5v to supply the teensy and the 9v to supply the motors (you may need a voltage regulator to get to 6v). But it should provide you need. But when all is said and done you need to do some homework on what your power needs are in Amps and Voltage distribution.
 
Wait, can the teensy 4.1 vin pin drive 6V?

To be honest I can't remember what the max voltage is that you can apply to the Vin pin but 6v is probably pushing it (just a guess). Also have to remember if you use external voltage you probably want to cut the jumper between the Vin and VUsb. See the pinout card.

This is the warning from the product page:
When USB power is not used, 5V power may be applied to the VIN pin. Because VIN & VUSB are connected, power should not be applied to VIN while a USB cable is used, to prevent the possibility of power flowing back into your computer. Alternately, a pair of pads on the bottom side may be cut apart, to separate VUSB from VIN, allowing power to be safely applied while USB is in use. (TODO: VUSB-VIN pads photo, right side)
 
Note: I am a software guy... But..

If you look at the T4.1 schematic it shows a voltage regulator that in main part says range up to 5.5v, but in the spec part it says absolute max 6v.
So you might be able to live dangerously and try 6v, but it may depend on how much current you are trying to push through it. If just a trickle than maybe fine.

Also as I know that the VR has been changed a few times due to part shortages, if I were doing more than just a one off design, I would not push it as...

Again EE types could probably give more complete list of options, but, again if me, I might try:
a) inline diode, that I believe many of them drop about .7v

b) Use some form of external VR or DC/DC converter. I have done this on my own boards as the servos run at about 12v...
Choosing a VR for 6v you need to make sure that the one you choose can run on 6v. Some of them I have used needed higher.

Good luck
 
You can also use one of those power banks for cell phones. They come in various capacities and provide regulated output voltage.
 
Nvm I found a 5V power adapter from like 6 years ago in my dads car. It's also the perfect shape barely fitting into the slot I make for a big screw. Thanks for the help everyone.
 
You can also use one of those power banks for cell phones. They come in various capacities and provide regulated output voltage.

In general, power banks that support 6 volts directly are fairly rare. The majority of power banks just support 5 volt USB power.

The new standard is USB C PD (power delivery), which can provide USB 5 volt power, but a device can request that it get a specific voltage and a specific max amps. IIRC, 5, 9, 12, 15, and 20 volts are typical voltages that you can get from USB C PD, but I don't know if the newest version of PD allows for other voltages. You can get so called trigger cables that fix the voltage at 9, 12, 15, or 20 volts.

One problem with power banks is often times they are designed for cell phones, and if your project does not pull enough power, it will shut down.

My favorite power banks that include USB C PD and also have US style plugs for recharging are, which I use for powering digital cameras as well as charging cell phones:


The older standard is QC (quick charge) that cell phones can request higher voltages and amps. I am not aware of ways to plug into a USB C QC power source to get a specific voltage.

There are a few power banks that provide specific voltages in addition to USB (typically 9 volts and 12 volts). The only one that I'm aware of that produces 6 volts is the AILI power bank (sold by a few different sellers), which needs 6 18650 batteries (you would need to buy the 18650 batteries separately):


In the past, there was a power bank where you could dial in the voltage, but it does not appear to be made any more.

One way to get specific voltages is to use step-up or boost (convert a smaller voltage to higher voltage), step-down (convert a higher voltage to lower voltage), or step-up/step-down (convert high/low voltage to a specific voltage). Note, there are various trade-offs involved such as max power the regulator can draw, max power that your battery provides, the amount of heat generated, and how much power is lost during conversion. I tend to go to pololu.com to get them:


So you might want to consider 2 voltage regulators, one for producing the power for the Teensy (3.7 - 5.5 volts), and the other for your motor. You would plug these into the same power source. Or get one regulator for the motor and get a power supply that provides 2 separate power ports including a USB port for the Teensy.

If you go to shops that support radio controlled cars, etc. they often times have batteries with different voltages. For camera stuff, I've been playing with battery holders for Sony NP-F batteries used for video. The camera batteries tend to have 2 li-on cells, so they produce voltages between 8.4 volts (when freshly charged) and 7.0 volts (when nearly depleted).

In terms of AA batteries, they also can vary in terms of voltage produced. Non-rechargeable batteries start out at 1.5 volts, but after use, they quickly put out a lower charge. So if you have a 4 battery holder, it will initially produce 6 volts, but it will drop over time. Rechargeable batteries produce voltages around 1.2 volts (so a 4 battery holder would produce 4.8 volts), but again the voltage varies over time.
 
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It is possible to power a Teensy 4.1 from "6V" sort of. As mentioned above, it depends which batteries you use, (their chemistry, or more to the point, their output voltage.) You shouldn't exceed 5.5V I believe. However, remember the I/O drivers for Teensy are 3.3V and are not 5V tolerant, even for a millisecond! So this means any connections to your motor have to be through some sort of driver. This can be as simple as a transistor or FET, or some sort of specialized driver. The driver needs to accept a 3.3V input as well as a near ground level input to change states. Motor inductance can create inductive spikes on the voltage, so some sort of diode clamp is usually used. Many times (but not all) the diode clamps are integrated with the driver.

I have powered 5V devices with a 6V sealed lead acid battery and a series diode (or two) to drop the voltage to under 5.3V. A SLA battery outputs 6.4V and may destroy the Teensy's voltage regulator. This is why others have asked specifically what kind of battery you planned on.

The Teensy is quite a nice, and powerful computing device, but it is sensitive to both input voltage at the power supply and on it's I/O pins.
 
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