Tiny DC-DC constant current switching power supply
TheMerovingian, Sun Feb 13 2011, 04:50PMI came across those small switchmode constant currend power supplies with buck-boost capabilities and I want to replicate some similar. From photos taken i was able to identify two ICs but with "obscure" markings, one is "101" and the other "7441" do you know something similar? I wasn't able to find anything about these parts. Have anyone reverse-engineered one of these in order to improve their current capabilities and so on?
All i was able to understant is that driver pushes current high side, since the output-ground pin is tied to the input-ground pin. So it must use some specialized switchmode driver ICs...
UPDATE: the 7441 is some reverse polarity protection, so the real switching IC is the "101" (integrated switch probably)
Re: Tiny DC-DC constant current switching power supply
Conundrum, Sun Feb 13 2011, 07:00PM
mc34063 maybe?
i've used one to make an led drive before.
worked well, the only problem was current sharing between the diodes...
Also an idea, some newer LED backlit laptop panels use a 5 pin SOIC as the backlight driver.
says 3A024 on it...
-A
Conundrum, Sun Feb 13 2011, 07:00PM
mc34063 maybe?
i've used one to make an led drive before.
worked well, the only problem was current sharing between the diodes...
Also an idea, some newer LED backlit laptop panels use a 5 pin SOIC as the backlight driver.
says 3A024 on it...
-A
Re: Tiny DC-DC constant current switching power supply
TheMerovingian, Sun Feb 13 2011, 07:21PM
The mc34063 pinout is different but seems a good alternative. Cannot find anything 'bout 3A024 execpt it is a voltage detector of some sorts in the turuta smd handbook
what about those "anonimous" markings... The 101 is a zener in most databases
maybe it is L01 or I01 or even L02 or I02
All i know it is a sot-23 5-pin switching controller of some type Vin min 2.0V , 5.5V Max. , 1.5A max . I don't understant how it can achieve buck boost using a grounded output without inverting the voltage....
Maybe it is boost and down-regulating PWM... (noisy)
TheMerovingian, Sun Feb 13 2011, 07:21PM
The mc34063 pinout is different but seems a good alternative. Cannot find anything 'bout 3A024 execpt it is a voltage detector of some sorts in the turuta smd handbook
what about those "anonimous" markings... The 101 is a zener in most databases
maybe it is L01 or I01 or even L02 or I02
All i know it is a sot-23 5-pin switching controller of some type Vin min 2.0V , 5.5V Max. , 1.5A max . I don't understant how it can achieve buck boost using a grounded output without inverting the voltage....
Maybe it is boost and down-regulating PWM... (noisy)
Re: Tiny DC-DC constant current switching power supply
Meatball, Sun Feb 13 2011, 10:48PM
Ah, the flexdrive V5.
If there were anything you could improve on that circuit, Dr Lava himself would have done it already. That circuit is very efficient, and its very flexible, stable, and protected.
Dr Lava sells them all over the place.
He is on photonlexicon I believe, but not active much. Otherwise I would recommend you ask him!
Meatball, Sun Feb 13 2011, 10:48PM
Ah, the flexdrive V5.
If there were anything you could improve on that circuit, Dr Lava himself would have done it already. That circuit is very efficient, and its very flexible, stable, and protected.
Dr Lava sells them all over the place.
He is on photonlexicon I believe, but not active much. Otherwise I would recommend you ask him!
Re: Tiny DC-DC constant current switching power supply
TheMerovingian, Sun Feb 13 2011, 10:59PM
Yeah. It would be nice to know what type of amazing controller is he using. A buck boost converter with positive output and grounded negative output is very interesting.
I tried to ask him but I am afraid that he would think that i'm trying to reverse engineer the thing or trying to build my own drivers.. so i doubt he will answer me.... he deleted the markings on the IC in the manual.. so he is not willing to give away his secrets
From the differences with flexdrive V4 i determined that the critical part is the "101" pwm sot-23-5 controller but i could't find it even on the turuta (yet the 2007 edition) smd handbook. THe current sensing resistor is probably a 0.05ohm smd... the rest seems simple (voltage references, filter capacitors). All switching is done by the magical "101" . Probably it also sinchronously rectify the voltage. I will go mad soon
TheMerovingian, Sun Feb 13 2011, 10:59PM
Yeah. It would be nice to know what type of amazing controller is he using. A buck boost converter with positive output and grounded negative output is very interesting.
I tried to ask him but I am afraid that he would think that i'm trying to reverse engineer the thing or trying to build my own drivers.. so i doubt he will answer me.... he deleted the markings on the IC in the manual.. so he is not willing to give away his secrets
From the differences with flexdrive V4 i determined that the critical part is the "101" pwm sot-23-5 controller but i could't find it even on the turuta (yet the 2007 edition) smd handbook. THe current sensing resistor is probably a 0.05ohm smd... the rest seems simple (voltage references, filter capacitors). All switching is done by the magical "101" . Probably it also sinchronously rectify the voltage. I will go mad soon
Re: Tiny DC-DC constant current switching power supply
Wolfram, Mon Feb 14 2011, 01:06AM
It might be this
chip.
Wolfram, Mon Feb 14 2011, 01:06AM
It might be this
chip.Re: Tiny DC-DC constant current switching power supply
Steve Conner, Mon Feb 14 2011, 09:54AM
It must be an inverting converter with positive input and negative output. The only buck-boost converters with positive input and positive output are the Cuk and SEPIC, and they both require two inductors, but your board only has one.
The LM3410 doesn't seem to do inverting.
Steve Conner, Mon Feb 14 2011, 09:54AM
It must be an inverting converter with positive input and negative output. The only buck-boost converters with positive input and positive output are the Cuk and SEPIC, and they both require two inductors, but your board only has one.
The LM3410 doesn't seem to do inverting.
Re: Tiny DC-DC constant current switching power supply
TheMerovingian, Mon Feb 14 2011, 11:24AM
That's why i'm getting mad on it. It also has grounded negative output. How do the hell measures current without a differential amplifier circuit??
TheMerovingian, Mon Feb 14 2011, 11:24AM
That's why i'm getting mad on it. It also has grounded negative output. How do the hell measures current without a differential amplifier circuit??
Re: Tiny DC-DC constant current switching power supply
Steve Conner, Mon Feb 14 2011, 11:28AM
Many of these chips have a differential amp built in for high-side current sensing.
I used to design laser drivers, and mine simply used a differential amp made from an op-amp. The high-end ones used a dedicated current-sense amplifier chip made by Burr Brown, I can't remember the part number.
Steve Conner, Mon Feb 14 2011, 11:28AM
Many of these chips have a differential amp built in for high-side current sensing.
I used to design laser drivers, and mine simply used a differential amp made from an op-amp. The high-end ones used a dedicated current-sense amplifier chip made by Burr Brown, I can't remember the part number.
Re: Tiny DC-DC constant current switching power supply
Conundrum, Mon Feb 14 2011, 12:07PM
Shame they don't make a PIC 5 or 6 pin with high current outputs and an A-D.
This would be pretty neat for lasers, etc and also save a lot of hassle when designing small circuits.
-A
#include "1W_laser_sendmeplease_kthx.h"
Conundrum, Mon Feb 14 2011, 12:07PM
Shame they don't make a PIC 5 or 6 pin with high current outputs and an A-D.
This would be pretty neat for lasers, etc and also save a lot of hassle when designing small circuits.
-A
#include "1W_laser_sendmeplease_kthx.h"
Re: Tiny DC-DC constant current switching power supply
Steve Conner, Mon Feb 14 2011, 12:13PM
Well, they would convert the circuit design hassle into assembly programming hassle.
Atmel sell a range of tiny AVRs designed to drive lamp ballasts and the like. I think they have that niche.
Steve Conner, Mon Feb 14 2011, 12:13PM
Well, they would convert the circuit design hassle into assembly programming hassle.
Atmel sell a range of tiny AVRs designed to drive lamp ballasts and the like. I think they have that niche.
Re: Tiny DC-DC constant current switching power supply
TheMerovingian, Mon Feb 14 2011, 12:36PM
With internal switch and sinchronous rectifiers?
How it is possible that it uses direct negative-ground connection? It can be only boost or only buck, or SEPIC, but i don't see two inductors and the only capacitors are tied to negative ground...
The solution must be simple but brilliant...
EDIT:
What it the "inductor" is in reality a small transformer? using a flyback topology? It could make sense.
MicroBoost drive manual-> http://hacylon.case.edu/ebay/laser_diode/MicroFlexDrive%20User%20Manual.pdf
TheMerovingian, Mon Feb 14 2011, 12:36PM
Steve McConner wrote ...
Well, they would convert the circuit design hassle into assembly programming hassle.
Atmel sell a range of tiny AVRs designed to drive lamp ballasts and the like. I think they have that niche.
Well, they would convert the circuit design hassle into assembly programming hassle.
Atmel sell a range of tiny AVRs designed to drive lamp ballasts and the like. I think they have that niche.
With internal switch and sinchronous rectifiers?
Steve McConner wrote ...
It must be an inverting converter with positive input and negative output. The only buck-boost converters with positive input and positive output are the Cuk and SEPIC, and they both require two inductors, but your board only has one.
The LM3410 doesn't seem to do inverting.
It must be an inverting converter with positive input and negative output. The only buck-boost converters with positive input and positive output are the Cuk and SEPIC, and they both require two inductors, but your board only has one.
The LM3410 doesn't seem to do inverting.
How it is possible that it uses direct negative-ground connection? It can be only boost or only buck, or SEPIC, but i don't see two inductors and the only capacitors are tied to negative ground...
The solution must be simple but brilliant...
EDIT:
What it the "inductor" is in reality a small transformer? using a flyback topology? It could make sense.
MicroBoost drive manual-> http://hacylon.case.edu/ebay/laser_diode/MicroFlexDrive%20User%20Manual.pdf
Re: Tiny DC-DC constant current switching power supply
Steve Conner, Mon Feb 14 2011, 01:57PM
If it were a transformer, you could see that it had more than 2 terminals.
I was wrong, it is possible to make a buck-boost converter with a single inductor, but 2 power switches are needed. See Figure 22 here.
Steve Conner, Mon Feb 14 2011, 01:57PM
If it were a transformer, you could see that it had more than 2 terminals.
I was wrong, it is possible to make a buck-boost converter with a single inductor, but 2 power switches are needed. See Figure 22 here.
Re: Tiny DC-DC constant current switching power supply
Wolfram, Mon Feb 14 2011, 03:18PM
See the last picture in the microflexdrive manual, there appears to be a BGA IC in the shadow of the inductor, between the ceramic caps. I found hints that the flexdrive was based on the TPS63010 , which is in a tiny 20-pin BGA that looks to be about the right size. It's a grounded-input grounded-output buck boost converter, so it makes sense. The SOT23-5 chip on the other side of the board might be a current sense amplifier or something like that.
Wolfram, Mon Feb 14 2011, 03:18PM
See the last picture in the microflexdrive manual, there appears to be a BGA IC in the shadow of the inductor, between the ceramic caps. I found hints that the flexdrive was based on the TPS63010
, which is in a tiny 20-pin BGA that looks to be about the right size. It's a grounded-input grounded-output buck boost converter, so it makes sense. The SOT23-5 chip on the other side of the board might be a current sense amplifier or something like that.Re: Tiny DC-DC constant current switching power supply
TheMerovingian, Mon Feb 14 2011, 04:23PM
The 5-pin chip gets hot according to forum discussion under heavy load. In fact people make efforts in heatsinking it as good as possible (also the manual says it). But the difference amplifier makes sense, since the output is grounded.
EDIT: You are right. I have found a photo of it http://jake.tscsupport.com/images/Laser/chipped_flexdrive.jpg showing almost clearly it is the TPS63010 IC. Too bad it is too small to solder without specialized tools....
TheMerovingian, Mon Feb 14 2011, 04:23PM
Anders M. wrote ...
See the last picture in the microflexdrive manual, there appears to be a BGA IC in the shadow of the inductor, between the ceramic caps. I found hints that the flexdrive was based on the TPS63010 , which is in a tiny 20-pin BGA that looks to be about the right size. It's a grounded-input grounded-output buck boost converter, so it makes sense. The SOT23-5 chip on the other side of the board might be a current sense amplifier or something like that.
See the last picture in the microflexdrive manual, there appears to be a BGA IC in the shadow of the inductor, between the ceramic caps. I found hints that the flexdrive was based on the TPS63010
, which is in a tiny 20-pin BGA that looks to be about the right size. It's a grounded-input grounded-output buck boost converter, so it makes sense. The SOT23-5 chip on the other side of the board might be a current sense amplifier or something like that.The 5-pin chip gets hot according to forum discussion under heavy load. In fact people make efforts in heatsinking it as good as possible (also the manual says it). But the difference amplifier makes sense, since the output is grounded.
EDIT: You are right. I have found a photo of it http://jake.tscsupport.com/images/Laser/chipped_flexdrive.jpg showing almost clearly it is the TPS63010 IC. Too bad it is too small to solder without specialized tools....
Re: Tiny DC-DC constant current switching power supply
Nicko, Mon Feb 14 2011, 04:50PM
In fact, my youngest son & I have just made an anodising setup so that we can turn nice knurled laser pens and anodise them with nice colours as a little side-line for him...
Cheers
Nicko, Mon Feb 14 2011, 04:50PM
TheMerovingian wrote ...
I came across those small switchmode constant currend power supplies with buck-boost capabilities and I want to replicate some similar...
I suspect this is based on the TPS61040/TPS61041 - I have used exactly these devices for constant current sources for laser diodes. Should also say that I really like these chips as a general purpose LV switcher - they are just very nice & easy...I came across those small switchmode constant currend power supplies with buck-boost capabilities and I want to replicate some similar...
In fact, my youngest son & I have just made an anodising setup so that we can turn nice knurled laser pens and anodise them with nice colours as a little side-line for him...
Cheers
Re: Tiny DC-DC constant current switching power supply
Martin King, Mon Feb 14 2011, 05:00PM
AVR :-
Martin.
Martin King, Mon Feb 14 2011, 05:00PM
Conundrum wrote ...
Shame they don't make a PIC 5 or 6 pin with high current outputs and an A-D.
Shame they don't make a PIC 5 or 6 pin with high current outputs and an A-D.
AVR :-
Martin.
Re: Tiny DC-DC constant current switching power supply
TheMerovingian, Mon Feb 14 2011, 07:49PM
THe front IC is the TPS63010 as shown in photo. THe 5 pin device may be de-facto the IC you have pointed out (heatsinking) , it is unclear why it is designed this way.
I have found valid alternatives to the TPS63030 in a more convenienta package, small but solderable (i have used a similar ic , the TPS61200DRCT 3.25 x 3.25 footprint, in a similar package for a micro dc-dc boost converter for DAFC single cells to power 3.3V leds).
TheMerovingian, Mon Feb 14 2011, 07:49PM
Nicko wrote ...
In fact, my youngest son & I have just made an anodising setup so that we can turn nice knurled laser pens and anodise them with nice colours as a little side-line for him...
Cheers
TheMerovingian wrote ...
I came across those small switchmode constant currend power supplies with buck-boost capabilities and I want to replicate some similar...
I suspect this is based on the TPS61040/TPS61041 - I have used exactly these devices for constant current sources for laser diodes. Should also say that I really like these chips as a general purpose LV switcher - they are just very nice & easy...I came across those small switchmode constant currend power supplies with buck-boost capabilities and I want to replicate some similar...
In fact, my youngest son & I have just made an anodising setup so that we can turn nice knurled laser pens and anodise them with nice colours as a little side-line for him...
Cheers
THe front IC is the TPS63010 as shown in photo. THe 5 pin device may be de-facto the IC you have pointed out (heatsinking) , it is unclear why it is designed this way.
I have found valid alternatives to the TPS63030 in a more convenienta package, small but solderable (i have used a similar ic , the TPS61200DRCT 3.25 x 3.25 footprint, in a similar package for a micro dc-dc boost converter for DAFC single cells to power 3.3V leds).
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