Touchstone Semi?

'Of course' means you never get something for nothing. If the TI part costs way less than the corresponding LT part, then similar performance is just the luck of the draw.

"Typical Nonlinearity < 0.5 dB" == +/- 6% Non-linearity ;-) ...Jim Thompson

--
| James E.Thompson                                 |    mens     | 
| Analog Innovations                               |     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.

But the fact is, you can't buy a part like that anywhere else. Same for some of the log amps AD offers.

When I think back, there is hardly ever a need for "precision linear" in my line of work. I could always clamp, servo or auto-calibrate things because I did not want to rely on single-source high precision stuff from a large manufacturer where a lot of "key account thinking" is customary.

--
Regards, Joerg 

http://www.analogconsultants.com/

Yep. Always been my policy. Jelly bean parts plus some smarts... auto-cal, whatever. Dirt cheap and repeatable/manufacturable. ...Jim Thompson

--
| James E.Thompson                                 |    mens     | 
| Analog Innovations                               |     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.

Wrong polarity marked for the iinput pins.

Regards, Mikko

The polarity looks right to me, once you fix the other thing.

--

John Larkin Highland Technology, Inc

jlarkin at highlandtechnology dot 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

way less than the corresponding LT part, then similar performance is just the luck of the draw.

Other manufacturers made "second source" parts which met the original specifications. The TI parts might have been cheap, but they weren't second sourced.

TI might have fabs all over, so you shouldn't get screwed by a fire knocking out a particular fab for a year or so, but they've also got a marketing department who can shut down all the fabs at once.

--
Bill Sloman, Sydney

I

en

d no worries about discontinuing parts, face it, they're still making produ cts pushing 45 years of legacy!

The LT1028 certainly had a horrible output stage (though less horrible than the 741/748), but it solved a few problems for me back in the

1980s. The AD797 was a whole lot nicer, but only became available about a decade later, when Analog Devices had got itself a much fancier fabrication process.

--
Bill Sloman, Sydney

e

se,

hly

if

nd

ive

e o

ot

w

You've got to keep in mind that krw isn't very intelligent. He doesn't appreciate subtle improvements, because he's unaware of the problem they were designed to solve.

--
Bill Sloman, Sydney

I thought you were the penny-pincher, here. Cost is king. ;-)

I'm looking at some MicroChip opamps now because they've quoted a really nice price. I hadn't ever considered them for linears before. I never even thought of them even *doing* linears but they've got some selection.

Unless you're doing some really simple stuff, anymore, you simply can't have multiple sources for everything. Once you go single source for a couple of things, you might just as well forget the whole problem.

krw certainly has no clue how power steering works >:-}

The Domino Directory is my friend ;-) ...Jim Thompson

--
| James E.Thompson                                 |    mens     | 
| Analog Innovations                               |     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.

Of course it doesn't give me prices. No, that's what the FAEs are for. ;-)

Sure, but they're EXPENSIVE. Up until quite recently, their model didn't fit. As I said, they're trying to push into the market. We'll see.

Their production is all over. We use a bunch of their stuff but try not to. They're a PITA to work with.

*WAY* TOO EXPENSIVE. Not going to happen. They're not even on the approved supplier list. Purchasing would laugh me out of the building. ;-)

Once again, proving what a useless old has-been hen you really are.

worries about discontinuing parts, face it, they're still making products pushing 45 years of legacy!

will have one too, rest assured.

Ok, but the point is the claim does not hold. Actually I was hoping you would find something. I will need to use this part in a project and although it may work well, it is not well spec'd when used as a VCO. They show how to do it, but there is no real formula for frequency vs. the control input. On the other hand, the FAE was very helpful and did some testing to show the part would indeed work as a VCO at this frequency, etc.

--

Rick

What the heck does *that* mean?

--

Rick

the

each.

have

For opamps you normally have at least that. For MCUs a lot of the Asian makers would have virtually no selection guide, just a list of the part numbers with some very simple description. No indication of how one part is different from another. I contacted a couple of them and asked why they don't have any sort of selection guide, the reply was always "you can download the data sheets", yeah, right.

That is the main reason I've never used an Asian source for MCUs.

thwir

That is the BIGGEST failing of many manufacturers in my opinion, when the first thing you have to decide to view their products is to select a marketing area. This shows how the company is actually internally oriented and not customer oriented in my opinion.

That usually makes me leave the site.

BTW, learn to trim your posts...

--

Rick

worries about discontinuing parts, face it, they're still making products pushing 45 years of legacy!

will have one too, rest assured.

7.9pF is so low as to make the oscillation frequency highly dependent on stray capacitance.

You might try characterizing it by using a much larger cap, then monitoring both the RSET pin and the CSET pin versus the voltage on the CNTRL pin.

My educated bet, since I've been designing ramp-type VCO's since the mid '60's, is that RSET will track CNTRL, most likely 1:1, but could be 1:1 with an offset (a NMOS G-S drop).

The CSET pin will have a ramp up, then discharge. Properly done, the fall time will be some set fraction of the ramp-up time. Crudely it may snap low.

Take that data and report back. Maybe I can make an educated guess of chip contents.

The data sheet DOES provide some information (pasting crudely)...

THEORY OF OPERATION The TS3002 is a user-programmable oscillator where the period of the square wave at its FOUT terminal is generated by an external resistor and capacitor pair. The output frequency is given by:

FOUT (kHz) = 1tFOUT ( s) 1E k RSET MÙ x CSET(pF)

where the scalar k is approximately 1.19. With an RSET = 4.32MÙ and a CSET = 7.9pF,

the output frequency is approximately 25kHz with a 50% duty cycle.

As design aids, Tables 1 lists TS3002?s typical FOUT for various standard values for RSET with CSET = 7.9pF and Table 2 lists typical FOUT for various standard values for CSET with RSET = 4.32MÙ. The TS3002 also provides a separate PWM output signal at its PWMOUT terminal that is anti-phase with respect to FOUT. In addition, applying a voltage at the CNTRL both enables the TS3002?s internal PWM engine as well as adjusting the duty cycle from 12% to 90%. A dc control voltage equal to 0.03 x VDD applied to the CNTRL pin enables the PWM engine to set the duty cycle to 12%. A dc control voltage equal to 0.27 x VDD increases the duty cycle to 90% and connecting CNTRL to VDD disables the PWM engine altogether. Configured for nominal operation (PWM engine OFF, BOOST pin to GND), the supply current of the TS3002 is 1ìA; enabling the PWM engine increases the TS3002 operating supply current as shown in the electrical specification table. The BOOST pin controls the propagation delay of the TS3002?s internal comparators. When BOOST is connected to GND, the TS3002?s maximum programmable operating frequency is ~90kHz. Connecting the BOOST pin to VDD reduces the propagation delay of the internal oscillators, thereby extending the high end maximum operating frequency to 290kHz.

Table 1: FOUT vs RSET, CSET = 7.9pF RSET (MÙ) FOUT (kHz)

1 106 2.49 43 4.32 25 6.81 16 9.76 11

Table 2: FOUT vs CSET, RSET = 4.32MÙ CSET (pF) FOUT (kHz)

5 39 7.9 25 10 19 15 13 20 10 ...Jim Thompson

--
| James E.Thompson                                 |    mens     | 
| Analog Innovations                               |     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.

tick,

parts

the

each.

have

thwir

"cheap."

a

Invest in some scroll bars.

--

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

Well? You really aren't very intelligent. You have no technology value-added, so you name call... like your white-trash buddies here.

The Domino Directory is my friend... I'm going to catch up to you, and you will find it _most_ unpleasant when I do ;-) ...Jim Thompson

--
| James E.Thompson                                 |    mens     | 
| Analog Innovations                               |     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.