Hydra: a triple-output power supply - Page 1
Forum section: electronics / general

author: RR
author_rank: Contributor
timestamp: June 23, 2014, 04:43:32 pm
content: Just browsed kickstarter projects and bumped on thishttps://www.kickstarter.com/projects/1107117096/hydra-a-triple-output-power-supply-for-electronicslooks like it was already shippedso anyone have one of these? highres pics? What regulator is used?

author: Lupin
author_rank: Newbie
timestamp: June 23, 2014, 09:19:28 pm
content: Three SMPS controllers and a microcontroller for 170 USD? Who'd fall for that?DC input makes it harder to carry around because you always have to use an AC wall adapter and cable.Screw terminals will wear out, banana plug sockets would be much better.Outputs aren't isolated, so they can't be connected in series. Maybe they can be paralleled.No idea about the output protection, but I wouldn't be surprised if the SMPS circuits are built from a datasheet example (without any real protection).I don't see any serious filter caps or output inductor (PI-Filter). This sing surely generates a fair amount of AC.It also needs a PC to operate... Some kind of stand alone input method would be nice.But it's a neat design and has a nice case... Looks like a good deal ;-)I'd love to see a power supply in the same form factor, battery powered and with a fixed output power instead of fixed output voltage / current.I mean something that can generate e.g. 0V to 500V (wide range to cover all applications) but is limited to e.g. 20 Watts. So you can get 5V at 4 Amps and 500V at 40mA.It could surely be built using a flyback transformer with switchable windings. If the output would be linear regulated then it'd be the perfect tool to carry around.Edit: I just checked their website, looks like they dropped the price to 99$ which sounds more reasonable.

author: theatrus
author_rank: Frequent Contributor
timestamp: June 24, 2014, 05:21:27 am
content: Sounds like a well run project. Actual design, shipped. Using the KS money to buy a bulk production run and then sell the remainder, which is likely the lifetime of the product anyway.

author: leppie
author_rank: Frequent Contributor
timestamp: June 24, 2014, 06:31:33 am
content: They seem to be selling it for $99 on their store now.

author: MacAttak
author_rank: Unknown
timestamp: June 27, 2014, 05:08:27 pm
content: I have one. Do you still want good photos?It's kinda neat. Three individual power supply channels, software controlled and monitored. There is a bluetooth module option that lets you operate it without needing a PC connection. You only need the PC connection to set the output levels by the way - not needed for actual operation unless you want to monitor the output.You aren't going to be drawing a huge amount of power through it, but not bad when you want multiple voltage sources in a single project (like when dealing with mixed 5v/3v3) but don't want to spend time on a power regulator circuit.Granted, that doesn't happen very often to me so it gets very little use. Most of time I only have to worry about a single voltage source, and my single-output linear supply works fine for that.

author: MacAttak
author_rank: Unknown
timestamp: June 27, 2014, 05:14:24 pm
content: Quote from: Lupin on June 23, 2014, 09:19:28 pmMany of your questions are answered on the KS pagehttps://www.kickstarter.com/projects/1107117096/hydra-a-triple-output-power-supply-for-electronicsI don't recall any of the specs being revised during production, so these should still be accurate:Features of the HydraOne input, three independent outputsControl via USB, serial, or Bluetooth (iPhone or Android devices)Adjustable output current limitCurrent control mode allows the Hydra to act as a current source (drives high power LEDs, etc.)Charges batteries using the included PC software and a USB connectionCNC-machined, anodized aluminum enclosureOutput short circuit protectionThermal shutdownESD and surge protection on all inputs and outputsReverse polarity protection on voltage inputSpecificationsAccepts input voltages from 5.0V to 14.0VOutput voltages individually configurable from 3.0V to 12.0VOutput voltage resolution: 0.01 voltsMax continuous current per output: 2.5A at 5V (~12 watts available per output at any voltage level)Output voltage ripple: < 10mV peak-peak at 100mA, < 50mV peak-peak at 2.5ABuck-boost topology allows the input to be above, below, or equal to the outputsBluetooth expansion board supports Blueooth 4.0 ONLY

author: RR
author_rank: Contributor
timestamp: June 28, 2014, 03:23:23 pm
content: Teardown would be nice! thank you in advance

author: mcinque
author_rank: Unknown
timestamp: June 28, 2014, 03:39:55 pm
content: Quote from: RR on June 28, 2014, 03:23:23 pmServed!

author: RR
author_rank: Contributor
timestamp: June 28, 2014, 07:35:41 pm
content: Quote from: mcinque on June 28, 2014, 03:39:55 pmWell thats not enough for meI want to see detailsWhat buck boost is used? I guess thats the bigger SOIC chip so whats the small qfn next to it is? adc/dac/mcu? Dont see any current shunt so is current sensed over inductor? As well dont see any output capacitance. How is that CC mode solved?On the top side from right its probably some small step down for mcu next would be main mcu, between that and usb port i guess some ft232 or similar. But what is under that usb? that ssop chip? eeprom? last one 8leg soic looks like some P transistor.

author: MacAttak
author_rank: Unknown
timestamp: July 03, 2014, 12:59:57 am
content: Finally had some time to open it up and take some photos.Linear Tech LTC3112 buck/boost in each module. The smaller qfn next to it is a Microchip digital pot MCP4451-104E/ML.It looks like the output caps are the two larger ceramics. Not sure about what's used in current sensing - the 3112 datasheet makes me think it's done by black magic (didn't see where it talked about it). I tried to get close-up photos of all components in one of the output module sections, at least good enough to read any markings.I believe the 4-pin connector at top right is for an external bluetooth module (which I don't have). Yes, the 24-QFN chip between the mcu and usb connector is the usb bridge (Silicon Labs 2104).Yes, the 8-leg chip on top left is a P mosfet.I don't think the chip below the usb connector is eeprom. It's a 10-pin chip. The atmega168a has 512B eeprom storage on-chip. which should be plenty for what this product needs (calibration values and output setpoints). That one stumps me too, and searching for parts with those markings hasn't turned up anything. I thought it might have something to do with current monitoring, but that's just a simple trace up to an adc pin on the mcu for each channel - so it's not that. It appears to be tied to the input side of each module

author: MacAttak
author_rank: Unknown
timestamp: July 03, 2014, 01:11:49 am
content: Also, there is a datasheet for it:http://www.chrobotics.com/docs/Hydra_datasheet.pdfIt says that current control is done via the mcu:Quote

author: EEVblog
author_rank: Unknown
timestamp: July 03, 2014, 01:26:46 am
content: 12W output per channel?At say 85% efficiency, that's over 5W dissipation in that little case

author: MacAttak
author_rank: Unknown
timestamp: July 03, 2014, 03:10:04 am
content: The case is more hefty than it looks at first glance - milled/anodized aluminum.

author: theatrus
author_rank: Frequent Contributor
timestamp: July 03, 2014, 03:44:49 am
content: That's actually quite a nice case. I wonder how much that runs...

author: EEVblog
author_rank: Unknown
timestamp: July 03, 2014, 04:07:02 am
content: Quote from: MacAttak on July 03, 2014, 03:10:04 amOh, I thought it was plastic.

author: mij59
author_rank: Frequent Contributor
timestamp: July 03, 2014, 04:38:17 am
content: Although it is a metal case, there only the pcb to conduct the heat to the case.Wondering how hot it gets inside at full load.Any thermal images available ?

author: ScubaShan
author_rank: Contributor
timestamp: July 04, 2014, 09:33:25 am
content: Mine arrived yesterday, so far it seems like a great little unit and does exactly what it says on the tin.

author: BloodyCactus
author_rank: Frequent Contributor
timestamp: July 04, 2014, 02:27:43 pm
content: the 'rounded' cutouts around the square screw terminals...aaaaargh. so much trouble gone to, such nice case etc... the OCD in me raaaarrrr

author: jaxbird
author_rank: Frequent Contributor
timestamp: July 04, 2014, 02:58:20 pm
content: Quote from: BloodyCactus on July 04, 2014, 02:27:43 pmAgree, it ruins the nice look a bit, but I guess cheaper when they can CNC the whole piece using just a single 1/4" bit size or something like that.I think they should have used pcb sockets instead of screw terminals, but I guess it would be possible to solder in any 5.08mm pitch terminal or socket.If it had been isolated outputs and better current control I would be interested, without, it's not really that useful to have multiple channels.

author: peter.mitchell
author_rank: Super Contributor
timestamp: July 04, 2014, 03:08:11 pm
content: Quote from: MacAttak on July 03, 2014, 12:59:57 amhttp://www.intersil.com/content/dam/Intersil/documents/isl4/isl43640.pdf

author: MacAttak
author_rank: Unknown
timestamp: July 05, 2014, 04:56:58 am
content: I've not used one of those before, and not really sure why it would be needed here. It seems to me that mcu has plenty of ADC inputs and digital outputs for what this device is doing and wouldn't need to multiplex anything. Any ideas on the purpose of this chip here?

author: CanadianAvenger
author_rank: Regular Contributor
timestamp: July 06, 2014, 03:30:54 am
content: Quote from: MacAttak on July 05, 2014, 04:56:58 amAn analog mux is often used on the ISP programming pins, when they are shared with other devices [typically a 4053]. Not saying that's the case here, but given the proximity to the programming header, it is a possibility.