On Friday, December 21, 2012 10:17:44 PM UTC+1, Jim Thompson wrote:> On Fri, 21 Dec 2012 11:11:58 -0800 (PST), Klaus Kragelund >=20 > <klauskvik@hotmail.com> wrote: >=20 >=20 >=20 > >On Friday, December 21, 2012 6:16:02 PM UTC+1, John Larkin wrote: >=20 > >> On Fri, 21 Dec 2012 03:02:40 -0800 (PST), Klaus Kragelund >=20 > >>=20 >=20 > >> <klauskvik@hotmail.com> wrote: >=20 > >>=20 >=20 > >>=20 >=20 > >>=20 >=20 > >> >Hi >=20 > >>=20 >=20 > >> > >=20 > >>=20 >=20 > >> >The standard RS485 drivers available has a minimum voltage of 3V and =a rarther large drop voltage when loaded with the defined bus load for Modb= us of 54ohms, and this causes problems for our design since we have limited= power available for driving the bus>=20 > >>=20 >=20 > >> > >=20 > >>=20 >=20 > >> >So, we are thinking about designing our own driver in discrete compon=ents, so we can reduce the supply down to 2V and still comply with minimum = 1.5V differential voltage into 54ohms.>=20 > >>=20 >=20 > >> > >=20 > >>=20 >=20 > >> >We only need 115k baud, so we could use a tiny logic level FET as the=output stage. Shortcircuit protection would be done with a current limit c= ircuit along with a low value supply capacitance (to reduce peak power in t= he FETs)>=20 > >>=20 >=20 > >> > >=20 > >>=20 >=20 > >> >Backfeed would need to be solved with a beefy diode to a defined clam=p voltage.>=20 > >>=20 >=20 > >> > >=20 > >>=20 >=20 > >> >So, anyone been down this road, designing your own RS485 driver? >=20 > >>=20 >=20 > >> > >=20 > >>=20 >=20 > >> >Cheers >=20 > >>=20 >=20 > >> > >=20 > >>=20 >=20 > >> >Klaus >=20 > >>=20 >=20 > >>=20 >=20 > >>=20 >=20 > >>=20 >=20 > >>=20 >=20 > >> Just use a cmos quad xor gate; two paralleled sections for one phase, =two for>=20 > >>=20 >=20 > >> the other, with maybe 3.3 volt supply and 30 ohm source terminations. =There's no>=20 > >>=20 >=20 > >> need to use discrete fets. >=20 > >>=20 >=20 > >>=20 >=20 > >>=20 >=20 > >> We recently did this: >=20 > >>=20 >=20 > >>=20 >=20 > >>=20 >=20 > >> https://dl.dropbox.com/u/53724080/Circuits/ESM/Line_Drivers.pdf >=20 > >>=20 >=20 > >>=20 >=20 > >>=20 >=20 > >> The basic line driver is a couple of tiny-logic gates driven from comp=lementary>=20 > >>=20 >=20 > >> FPGA outputs. The downstream junk is selectable line driver equalizati=on, to>=20 > >>=20 >=20 > >> partially correct for CAT5 cable losses. This runs up to 125 MHz. >=20 > > >=20 > >Maybe a good point, if I can find a logic device that has low RDSon at 2=V.=20>=20 > > >=20 > >The ones I have found have 10ohms RDSon (NC7SZ74), but could parallel so=me of those to bring down the RDSon to the 2-3 ohms range>=20 > > >=20 > >Regards >=20 > > >=20 > >Klaus >=20 >=20 >=20 > Do you need to tri-state the driver? If so, Larkin's suggestion >=20 > doesn't work. Even with tri-state you have to watch out for "kick" >=20 > above/below rails. >=20Yes, I need to tristate the driver, since it is a 2 wire system, half duple= x. Regards Klaus
Discrete custom design of RS485 driver
Started by ●December 21, 2012
Reply by ●December 21, 20122012-12-21
Reply by ●December 21, 20122012-12-21
On Friday, December 21, 2012 11:41:12 PM UTC+1, John Larkin wrote:> On Fri, 21 Dec 2012 14:17:44 -0700, Jim Thompson >=20 > <To-Email-Use-The-Envelope-Icon@On-My-Web-Site.com> wrote: >=20 >=20 >=20 > >On Fri, 21 Dec 2012 11:11:58 -0800 (PST), Klaus Kragelund >=20 > ><klauskvik@hotmail.com> wrote: >=20 > > >=20 > >>On Friday, December 21, 2012 6:16:02 PM UTC+1, John Larkin wrote: >=20 > >>> On Fri, 21 Dec 2012 03:02:40 -0800 (PST), Klaus Kragelund >=20 > >>>=20 >=20 > >>> <klauskvik@hotmail.com> wrote: >=20 > >>>=20 >=20 > >>>=20 >=20 > >>>=20 >=20 > >>> >Hi >=20 > >>>=20 >=20 > >>> > >=20 > >>>=20 >=20 > >>> >The standard RS485 drivers available has a minimum voltage of 3V and=a rarther large drop voltage when loaded with the defined bus load for Mod= bus of 54ohms, and this causes problems for our design since we have limite= d power available for driving the bus>=20 > >>>=20 >=20 > >>> > >=20 > >>>=20 >=20 > >>> >So, we are thinking about designing our own driver in discrete compo=nents, so we can reduce the supply down to 2V and still comply with minimum= 1.5V differential voltage into 54ohms.>=20 > >>>=20 >=20 > >>> > >=20 > >>>=20 >=20 > >>> >We only need 115k baud, so we could use a tiny logic level FET as th=e output stage. Shortcircuit protection would be done with a current limit = circuit along with a low value supply capacitance (to reduce peak power in = the FETs)>=20 > >>>=20 >=20 > >>> > >=20 > >>>=20 >=20 > >>> >Backfeed would need to be solved with a beefy diode to a defined cla=mp voltage.>=20 > >>>=20 >=20 > >>> > >=20 > >>>=20 >=20 > >>> >So, anyone been down this road, designing your own RS485 driver? >=20 > >>>=20 >=20 > >>> > >=20 > >>>=20 >=20 > >>> >Cheers >=20 > >>>=20 >=20 > >>> > >=20 > >>>=20 >=20 > >>> >Klaus >=20 > >>>=20 >=20 > >>>=20 >=20 > >>>=20 >=20 > >>>=20 >=20 > >>>=20 >=20 > >>> Just use a cmos quad xor gate; two paralleled sections for one phase,=two for>=20 > >>>=20 >=20 > >>> the other, with maybe 3.3 volt supply and 30 ohm source terminations.=There's no>=20 > >>>=20 >=20 > >>> need to use discrete fets. >=20 > >>>=20 >=20 > >>>=20 >=20 > >>>=20 >=20 > >>> We recently did this: >=20 > >>>=20 >=20 > >>>=20 >=20 > >>>=20 >=20 > >>> https://dl.dropbox.com/u/53724080/Circuits/ESM/Line_Drivers.pdf >=20 > >>>=20 >=20 > >>>=20 >=20 > >>>=20 >=20 > >>> The basic line driver is a couple of tiny-logic gates driven from com=plementary>=20 > >>>=20 >=20 > >>> FPGA outputs. The downstream junk is selectable line driver equalizat=ion, to>=20 > >>>=20 >=20 > >>> partially correct for CAT5 cable losses. This runs up to 125 MHz. >=20 > >> >=20 > >>Maybe a good point, if I can find a logic device that has low RDSon at =2V.=20>=20 > >> >=20 > >>The ones I have found have 10ohms RDSon (NC7SZ74), but could parallel s=ome of those to bring down the RDSon to the 2-3 ohms range>=20 > >> >=20 > >>Regards >=20 > >> >=20 > >>Klaus >=20 > > >=20 > >Do you need to tri-state the driver? If so, Larkin's suggestion >=20 > >doesn't work. =20 >=20 >=20 >=20 > Why not? Use tri-state tiny-logic drivers. >=20 >=20 >=20 >=20 >=20 > Even with tri-state you have to watch out for "kick" >=20 > >above/below rails. >=20 >=20 >=20 > Kick? Logic chips can't drive transmission lines? Add some protection >=20 > if you expect lightning bolts. >=20We would need to add protection in any case to reduce the currents, the dri= ver IC would suffer from latchup problems if not. Cheers Klaus
Reply by ●December 21, 20122012-12-21
On Fri, 21 Dec 2012 14:52:43 -0800 (PST), Klaus Kragelund <klauskvik@hotmail.com> wrote:>On Friday, December 21, 2012 11:41:12 PM UTC+1, John Larkin wrote: >> On Fri, 21 Dec 2012 14:17:44 -0700, Jim Thompson >> >> <To-Email-Use-The-Envelope-Icon@On-My-Web-Site.com> wrote: >> >> >> >> >On Fri, 21 Dec 2012 11:11:58 -0800 (PST), Klaus Kragelund >> >> ><klauskvik@hotmail.com> wrote: >> >> > >> >> >>On Friday, December 21, 2012 6:16:02 PM UTC+1, John Larkin wrote: >> >> >>> On Fri, 21 Dec 2012 03:02:40 -0800 (PST), Klaus Kragelund >> >> >>> >> >> >>> <klauskvik@hotmail.com> wrote: >> >> >>> >> >> >>> >> >> >>> >> >> >>> >Hi >> >> >>> >> >> >>> > >> >> >>> >> >> >>> >The standard RS485 drivers available has a minimum voltage of 3V and a rarther large drop voltage when loaded with the defined bus load for Modbus of 54ohms, and this causes problems for our design since we have limited power available for driving the bus >> >> >>> >> >> >>> > >> >> >>> >> >> >>> >So, we are thinking about designing our own driver in discrete components, so we can reduce the supply down to 2V and still comply with minimum 1.5V differential voltage into 54ohms. >> >> >>> >> >> >>> > >> >> >>> >> >> >>> >We only need 115k baud, so we could use a tiny logic level FET as the output stage. Shortcircuit protection would be done with a current limit circuit along with a low value supply capacitance (to reduce peak power in the FETs) >> >> >>> >> >> >>> > >> >> >>> >> >> >>> >Backfeed would need to be solved with a beefy diode to a defined clamp voltage. >> >> >>> >> >> >>> > >> >> >>> >> >> >>> >So, anyone been down this road, designing your own RS485 driver? >> >> >>> >> >> >>> > >> >> >>> >> >> >>> >Cheers >> >> >>> >> >> >>> > >> >> >>> >> >> >>> >Klaus >> >> >>> >> >> >>> >> >> >>> >> >> >>> >> >> >>> >> >> >>> Just use a cmos quad xor gate; two paralleled sections for one phase, two for >> >> >>> >> >> >>> the other, with maybe 3.3 volt supply and 30 ohm source terminations. There's no >> >> >>> >> >> >>> need to use discrete fets. >> >> >>> >> >> >>> >> >> >>> >> >> >>> We recently did this: >> >> >>> >> >> >>> >> >> >>> >> >> >>> https://dl.dropbox.com/u/53724080/Circuits/ESM/Line_Drivers.pdf >> >> >>> >> >> >>> >> >> >>> >> >> >>> The basic line driver is a couple of tiny-logic gates driven from complementary >> >> >>> >> >> >>> FPGA outputs. The downstream junk is selectable line driver equalization, to >> >> >>> >> >> >>> partially correct for CAT5 cable losses. This runs up to 125 MHz. >> >> >> >> >> >>Maybe a good point, if I can find a logic device that has low RDSon at 2V. >> >> >> >> >> >>The ones I have found have 10ohms RDSon (NC7SZ74), but could parallel some of those to bring down the RDSon to the 2-3 ohms range >> >> >> >> >> >>Regards >> >> >> >> >> >>Klaus >> >> > >> >> >Do you need to tri-state the driver? If so, Larkin's suggestion >> >> >doesn't work. >> >> >> >> Why not? Use tri-state tiny-logic drivers. >> >> >> >> >> >> Even with tri-state you have to watch out for "kick" >> >> >above/below rails. >> >> >> >> Kick? Logic chips can't drive transmission lines? Add some protection >> >> if you expect lightning bolts. >> > >We would need to add protection in any case to reduce the currents, the driver IC would suffer from latchup problems if not.I've never seen a cmos chip latch up from driving a low-z load, including a short to either rail. You can get them pretty hot. Pushing a lot of current into an ESD diode can latch some parts. We use tiny logic drivers in the thing I posted, and in other products that we've sold thousands of, driving customer loads of all sorts, and haven't had any latchup problems. -- John Larkin Highland Technology, Inc jlarkin at highlandtechnology dot com http://www.highlandtechnology.com Precision electronic instrumentation Picosecond-resolution Digital Delay and Pulse generators Custom laser drivers and controllers Photonics and fiberoptic TTL data links VME thermocouple, LVDT, synchro acquisition and simulation
Reply by ●December 21, 20122012-12-21
On Fri, 21 Dec 2012 14:45:35 -0800, Joerg <invalid@invalid.invalid> wrote:>Jim Thompson wrote: >> On Fri, 21 Dec 2012 10:12:56 -0800, Joerg <invalid@invalid.invalid> >> wrote: >> >>> Klaus Kragelund wrote: >>>> On Friday, December 21, 2012 12:02:40 PM UTC+1, Klaus Kragelund >>>> wrote: >>>>> Hi >>>>> >>>>> >>>>> >>>>> The standard RS485 drivers available has a minimum voltage of 3V >>>>> and a rarther large drop voltage when loaded with the defined bus >>>>> load for Modbus of 54ohms, and this causes problems for our design >>>>> since we have limited power available for driving the bus >>>>> >>>>> >>>>> >>>>> So, we are thinking about designing our own driver in discrete >>>>> components, so we can reduce the supply down to 2V and still comply >>>>> with minimum 1.5V differential voltage into 54ohms. >>>>> >>>>> >>>>> >>>>> We only need 115k baud, so we could use a tiny logic level FET as >>>>> the output stage. Shortcircuit protection would be done with a >>>>> current limit circuit along with a low value supply capacitance (to >>>>> reduce peak power in the FETs) >>>>> >>>>> >>>>> >>>>> Backfeed would need to be solved with a beefy diode to a defined >>>>> clamp voltage. >>>>> >>>>> >>>>> >>>>> So, anyone been down this road, designing your own RS485 driver? >>>>> >>>> A rough first draft: >>>> >>>> www.electronicsdesign.dk/tmp/RS485_Custom.pdf >>> >>> Just a comment: Diodes are already in the FETs, in the form of body diodes. >> >> And generally not safe to use for repetitive pulses. ... > > >Why that? They are often used as regular power current paths. The >current rating is roughly the same as the FET itself, usually.But resistive, since it's a current path from the back of the die. Go ahead... I always enjoy your sound effects >:-}> > >> ... Some discrete >> FET's I was using at Zarlink came with a Schottky in the same package. >>I mis-spoke... make that Synaptics.> >With RF stuff all bets are off, RF transistors can be like the princess >on the pea. 3V reverse Vbe ... poof ... gone. Or gaoan, as they'd say at >one client. > >[...]Here today, China tomorrow ;-) ...Jim Thompson -- | James E.Thompson, CTO | mens | | Analog Innovations, Inc. | et | | Analog/Mixed-Signal ASIC's and Discrete Systems | manus | | Phoenix, Arizona 85048 Skype: Contacts Only | | | Voice:(480)460-2350 Fax: Available upon request | Brass Rat | | E-mail Icon at http://www.analog-innovations.com | 1962 | I love to cook with wine. Sometimes I even put it in the food.
Reply by ●December 21, 20122012-12-21
"Klaus Kragelund" <klauskvik@hotmail.com> wrote in message news:8f642a78-2a12-40c8-b77d-13ce5c75ee36@googlegroups.com...> Yes, could be a good idea, just need to add circuitry to draw the > carriers out of the base to switch them off fast.And that's not even that big of a deal, really -- if you run 2N4401/3 kind of hot (~20mA Ic, 2mA base drive, 680 ohm B-E resistor), you'll see edges under 100ns and storage time under 300ns (storage causes skew, but it's symmetrical in an H-bridge, so it causes shoot-through and delay). 115kbaud gives you almost 10us between edges, so there's tons of time for switching. The average switching transistor (like the little complementary gate drive things, or just a plain old ZTX651 or etc.) is even beefier, maintaining hFE > 100 at rated collector current. So, even saturated (where hFE is lower and stored charge piles up), they don't take much drive current at all, relative to what they're doing. They start looking like low Vgs(th) MOSFETs, with an input diode thrown in for convenience. Tim -- Deep Friar: a very philosophical monk. Website: http://seventransistorlabs.com
Reply by ●December 21, 20122012-12-21
Jim Thompson wrote:> On Fri, 21 Dec 2012 14:45:35 -0800, Joerg <invalid@invalid.invalid> > wrote: > >> Jim Thompson wrote: >>> On Fri, 21 Dec 2012 10:12:56 -0800, Joerg <invalid@invalid.invalid> >>> wrote: >>> >>>> Klaus Kragelund wrote: >>>>> On Friday, December 21, 2012 12:02:40 PM UTC+1, Klaus Kragelund >>>>> wrote: >>>>>> Hi >>>>>> >>>>>> >>>>>> >>>>>> The standard RS485 drivers available has a minimum voltage of 3V >>>>>> and a rarther large drop voltage when loaded with the defined bus >>>>>> load for Modbus of 54ohms, and this causes problems for our design >>>>>> since we have limited power available for driving the bus >>>>>> >>>>>> >>>>>> >>>>>> So, we are thinking about designing our own driver in discrete >>>>>> components, so we can reduce the supply down to 2V and still comply >>>>>> with minimum 1.5V differential voltage into 54ohms. >>>>>> >>>>>> >>>>>> >>>>>> We only need 115k baud, so we could use a tiny logic level FET as >>>>>> the output stage. Shortcircuit protection would be done with a >>>>>> current limit circuit along with a low value supply capacitance (to >>>>>> reduce peak power in the FETs) >>>>>> >>>>>> >>>>>> >>>>>> Backfeed would need to be solved with a beefy diode to a defined >>>>>> clamp voltage. >>>>>> >>>>>> >>>>>> >>>>>> So, anyone been down this road, designing your own RS485 driver? >>>>>> >>>>> A rough first draft: >>>>> >>>>> www.electronicsdesign.dk/tmp/RS485_Custom.pdf >>>> Just a comment: Diodes are already in the FETs, in the form of body diodes. >>> And generally not safe to use for repetitive pulses. ... >> >> Why that? They are often used as regular power current paths. The >> current rating is roughly the same as the FET itself, usually. > > But resistive, since it's a current path from the back of the die. >What's the difference? Whether 0.7V drops across a more or less resistive path, who cares? All that counts is total dissipation and that it's not too localized.> Go ahead... I always enjoy your sound effects >:-} > >> >>> ... Some discrete >>> FET's I was using at Zarlink came with a Schottky in the same package. >>> > > I mis-spoke... make that Synaptics. > >> With RF stuff all bets are off, RF transistors can be like the princess >> on the pea. 3V reverse Vbe ... poof ... gone. Or gaoan, as they'd say at >> one client. >> >> [...] > > Here today, China tomorrow ;-) >I sure hope we can at least keep high-end semiconductor engineering and processing in the country for a while, now that Obamacare is smothering much of the med device investment climate. We can't afford to lose such leadership positions but obviously that doesn't sink in on the hill :-( -- Regards, Joerg http://www.analogconsultants.com/
Reply by ●December 21, 20122012-12-21
On Fri, 21 Dec 2012 15:54:37 -0800, Joerg <invalid@invalid.invalid> wrote:>Jim Thompson wrote: >> On Fri, 21 Dec 2012 14:45:35 -0800, Joerg <invalid@invalid.invalid> >> wrote: >> >>> Jim Thompson wrote: >>>> On Fri, 21 Dec 2012 10:12:56 -0800, Joerg <invalid@invalid.invalid> >>>> wrote: >>>> >>>>> Klaus Kragelund wrote: >>>>>> On Friday, December 21, 2012 12:02:40 PM UTC+1, Klaus Kragelund >>>>>> wrote: >>>>>>> Hi >>>>>>> >>>>>>> >>>>>>> >>>>>>> The standard RS485 drivers available has a minimum voltage of 3V >>>>>>> and a rarther large drop voltage when loaded with the defined bus >>>>>>> load for Modbus of 54ohms, and this causes problems for our design >>>>>>> since we have limited power available for driving the bus >>>>>>> >>>>>>> >>>>>>> >>>>>>> So, we are thinking about designing our own driver in discrete >>>>>>> components, so we can reduce the supply down to 2V and still comply >>>>>>> with minimum 1.5V differential voltage into 54ohms. >>>>>>> >>>>>>> >>>>>>> >>>>>>> We only need 115k baud, so we could use a tiny logic level FET as >>>>>>> the output stage. Shortcircuit protection would be done with a >>>>>>> current limit circuit along with a low value supply capacitance (to >>>>>>> reduce peak power in the FETs) >>>>>>> >>>>>>> >>>>>>> >>>>>>> Backfeed would need to be solved with a beefy diode to a defined >>>>>>> clamp voltage. >>>>>>> >>>>>>> >>>>>>> >>>>>>> So, anyone been down this road, designing your own RS485 driver? >>>>>>> >>>>>> A rough first draft: >>>>>> >>>>>> www.electronicsdesign.dk/tmp/RS485_Custom.pdf >>>>> Just a comment: Diodes are already in the FETs, in the form of body diodes. >>>> And generally not safe to use for repetitive pulses. ... >>> >>> Why that? They are often used as regular power current paths. The >>> current rating is roughly the same as the FET itself, usually. >> >> But resistive, since it's a current path from the back of the die. >> > >What's the difference? Whether 0.7V drops across a more or less >resistive path, who cares? All that counts is total dissipation and that >it's not too localized. > > >> Go ahead... I always enjoy your sound effects >:-} >> >>> >>>> ... Some discrete >>>> FET's I was using at Zarlink came with a Schottky in the same package. >>>> >> >> I mis-spoke... make that Synaptics. >> >>> With RF stuff all bets are off, RF transistors can be like the princess >>> on the pea. 3V reverse Vbe ... poof ... gone. Or gaoan, as they'd say at >>> one client. >>> >>> [...] >> >> Here today, China tomorrow ;-) >> > >I sure hope we can at least keep high-end semiconductor engineering and >processing in the country for a while, now that Obamacare is smothering >much of the med device investment climate. We can't afford to lose such >leadership positions but obviously that doesn't sink in on the hill :-(Except for the expert witness stuff (3 weeks in Dallas Federal District Court starting around January 7 :-), all of my work is now west of Honolulu. ...Jim Thompson -- | James E.Thompson, CTO | mens | | Analog Innovations, Inc. | et | | Analog/Mixed-Signal ASIC's and Discrete Systems | manus | | Phoenix, Arizona 85048 Skype: Contacts Only | | | Voice:(480)460-2350 Fax: Available upon request | Brass Rat | | E-mail Icon at http://www.analog-innovations.com | 1962 | I love to cook with wine. Sometimes I even put it in the food.
Reply by ●December 21, 20122012-12-21
On 12/21/2012 6:54 PM, Joerg wrote:> > I sure hope we can at least keep high-end semiconductor engineering and > processing in the country for a while, now that Obamacare is smothering > much of the med device investment climate.I would love to hear some sort of rational explanation of how that is happening. Rick
Reply by ●December 21, 20122012-12-21
Jim Thompson wrote:> On Fri, 21 Dec 2012 15:54:37 -0800, Joerg <invalid@invalid.invalid> > wrote: > >> Jim Thompson wrote: >>> On Fri, 21 Dec 2012 14:45:35 -0800, Joerg <invalid@invalid.invalid> >>> wrote: >>> >>>> Jim Thompson wrote:[...]>>>>> ... Some discrete >>>>> FET's I was using at Zarlink came with a Schottky in the same package. >>>>> >>> I mis-spoke... make that Synaptics. >>> >>>> With RF stuff all bets are off, RF transistors can be like the princess >>>> on the pea. 3V reverse Vbe ... poof ... gone. Or gaoan, as they'd say at >>>> one client. >>>> >>>> [...] >>> Here today, China tomorrow ;-) >>> >> I sure hope we can at least keep high-end semiconductor engineering and >> processing in the country for a while, now that Obamacare is smothering >> much of the med device investment climate. We can't afford to lose such >> leadership positions but obviously that doesn't sink in on the hill :-( > > Except for the expert witness stuff (3 weeks in Dallas Federal > District Court starting around January 7 :-), all of my work is now > west of Honolulu. >Interesting. Mine is still mostly on US soil, or all of it right now. But medical has nearly evaporated from a consulting point of view, from>50% a few years ago down to <10%. Plenty of work here but allindustrial, oil, gas, aerospace and so on. That does not bode well for med-tech in our country. -- Regards, Joerg http://www.analogconsultants.com/
Reply by ●December 21, 20122012-12-21
rickman wrote:> On 12/21/2012 6:54 PM, Joerg wrote: >> >> I sure hope we can at least keep high-end semiconductor engineering and >> processing in the country for a while, now that Obamacare is smothering >> much of the med device investment climate. > > I would love to hear some sort of rational explanation of how that is > happening. >Many reasons. A major one is the new medical device tax. This will skim 2.3% off the top. From revenue. It means that start-up companies that typically do not turn a profit for easily the first 10 years will get burdened with it. For others that are in the disposables business and run on 5-10% profit margins one can easily see that it will wipe out a huge chunk of that. Then there's rationing that'll happen. Medical is a zero sum game, we can't run it on hot air (a.k.a. bonds) forever. We have already seen slashing of reimbursements. This will make certain higher end products unprofitable, and high-end is where our country excels. So while now everyone may be entitled to a free enema or flu shot there are likely going to be growing waiting lists when you need help with some serious stuff. Just like there are in Canada. This means less revenue for manufacturers. Next, capital gains taxes. Funding a start-up is a major risk for the investors. So if the rewards they can reap are majorly cut down by tax increases they will, obviously, curb their risk exposure. That's what I am seeing the most in the med venture space, a risk-averseness that I have not encountered ever in the past. And I am in med tech since the 80's. I could go on and on, but hopefully this suffices to explain some of the effects that I (and a lot of others) see coming or have already experienced. Personally I've seen things not being funded that used to be a sure thing 10 years ago, plus whole projects got canned that had progressed quite far. While people like me can move to other areas in engineering because I have kept a generalist attitude all my life that is no so for many others. My former employer is in the process of moving production to Costa Rica. Other companies have started layoffs: http://www.examiner.com/article/stryker-lays-1-000-people-off-blames-obamacare-s-medical-device-tax Where will these people find work? -- Regards, Joerg http://www.analogconsultants.com/
