39,594
edits
155-0032-00: Difference between revisions
Jump to navigation
Jump to search
no edit summary
(New page: The Tektronix 155-0032-00 is an amplifier chip made by Tektronix. It is packaged in a 16-pin DIP. It is used in the 335. The inputs and outputs are differential. The input diff...) |
No edit summary |
||
| (23 intermediate revisions by 4 users not shown) | |||
| Line 1: | Line 1: | ||
{{Monolithic IC | |||
It is | |Manufacturer=Tektronix | ||
It is | |Model=M55D | ||
The | |Part_nos=155-0032-00,155-0032-01 | ||
The input differential amplifier's emitters are brought out to pins 1 and 16 | |Description=differential amplifier | ||
|Used_in=335;464;465;465B;466;475;475A;475M;634;650;651;652;653;655;656;670;671;7A12;475;FG504;1440;1460;1480;1481;1482;1485 | |||
|Designers=Roy Hayes | |||
}} in a 16-pin DIP, designed by [[Roy Hayes]]. | |||
Regarding the 155-0032-xx, [[John Addis]] says, | |||
<blockquote> | |||
<p>The 155-0032-00’s IC process had an FT of 1.0 or 1.2 GHz (don’t remember), rather inadequate for the job. | |||
The on-chip resistors were diffused and thus had too poor a TC and tolerance for use as gain-setting resistors. | |||
</p> | |||
<p> | |||
As you can see, there are two separate gain selections determined by which set of emitters is chosen, pins 1 and 16 or 2 and 15. | |||
This selection is made off chip by choosing Q205 or Q215 to carry the current through R212. | |||
Pot R217 allows dc balance at 5 mV/div to match that at all other sensitivities, controlled elsewhere. | |||
</p> | |||
<p> | |||
Pin 12 ultimately selects which pair of the four output cross-connected transistors passes | |||
the signal current from the two transistors whose bases are connected to pin 4. | |||
Which pair of output transistors is chosen determines the polarity of the output signal. | |||
This same pair of transistors also enables variable gain by allowing | |||
a controlled amount of cross-coupling of the signal. | |||
</p> | |||
<p> | |||
This is an undesirable way of doing variable gain control, but neither Roy nor I knew that at the time. | |||
It is a noisy configuration. At the 0% signal gain there is lots of noise gain. | |||
It has poor thermal balance at anything other than 100% and the not very useful 0% signal gain. | |||
In between 0% and 100% gain, the circuit is poor in noise and thermal balance. | |||
I went on to use the same (Gilbert Multiplier) circuit in the [[155-0078-00|155-0078-xx (M84)]] and | |||
made the same bad choice again in the [[7A29]]. | |||
In our defense, with just two stages and the need to do both invert and variable gain control somewhere, there was not a lot of choice. | |||
</p> | |||
<p> | |||
It was not until I designed the [[M377]] for the 11000 series of plugins ([[11A32]], [[11A33]], [[11A34]], [[11A52]]) that I finally got it right. | |||
(See the British magazine Electronic Engineering, September, 1988, pp 40-41.) | |||
</p> | |||
<p> | |||
The M377 was a single channel plugin on a chip with 0 V common mode input and output voltages, | |||
excellent variable gain control, two four pole bandwidth limits, | |||
three outputs which could be separately inverted and turned on or off. | |||
</p> | |||
<p> | |||
It was the first wideband analog IC with level shift on chip (allowing 0 V common mode input and output and without PNP transistors), | |||
first wideband amplifier with any on-chip bandwidth limit selection, first to have more than two fixed gain settings (it has six), | |||
and first to require only one transient response adjustment (no thermals), | |||
and the first to have a highly linear relationship between a control voltage and gain. | |||
It also had excellent overdrive recovery. Live and learn. | |||
</p> | |||
</blockquote> | |||
The input differential amplifier's emitters are brought out to pins 1 and 16. | |||
Off-chip components provide frequency compensation and determine the gain. | |||
The chip has an input to select normal or inverted phase and an input to vary the | |||
"position", i.e., output current offset. | |||
* pin 1: emitter current source | * pin 1: emitter current source | ||
| Line 10: | Line 61: | ||
* pin 3: input balance | * pin 3: input balance | ||
* pin 4: bias | * pin 4: bias | ||
* pin 5: | * pin 5: −8V | ||
* pin 6: position current source | * pin 6: position current source | ||
* pin 7: ground | * pin 7: ground | ||
* pin 8: signal out | * pin 8: signal out − | ||
* pin 9: signal out + | * pin 9: signal out + | ||
* pin 10: position | * pin 10: position | ||
| Line 19: | Line 70: | ||
* pin 12: norm / -inv | * pin 12: norm / -inv | ||
* pin 13: +5V | * pin 13: +5V | ||
* pin 14: signal in | * pin 14: signal in − | ||
* pin 15: gain switching | * pin 15: gain switching | ||
* pin 16: emitter current source | * pin 16: emitter current source | ||
==Used in== | |||
* The 155-0032-00 is used in the front end of the [[335]] signal path, just after a JFET high-impedance buffer. It is discussed on page 3-5 of the 335 manual. | |||
* The 155-0032-00 is also used as the trigger amplifier in the [[465]]. In this application, the input differential amplifier has a total tail current of about 11 mA. | |||
* The 155-0032-00 is used as a vertical gain stage in the [[7A12]]. | |||
* [[475]] (U520, U720) | |||
* [[FG504]] (U770) | |||
* [[1440]] (-01), [[1460]] (-01), [[1478]] (-01) | |||
* [[1480]], [[1481]], [[1482]], [[1485]] | |||
* [[464]], [[465]], [[465B]], [[466]], [[475]], [[475A]], [[475M]] | |||
* [[634]], [[650]], [[651]], [[652]], [[653]], [[655]], [[656]], [[670]], [[671]] | |||
==Datasheet== | |||
* [[Media:Tek 155-0032-00.pdf|Tektronix 155-0032-00 Datasheet (PDF)]] | |||
==Diagrams== | |||
<gallery> | |||
Tek 155-0032-01 1.jpg|155-0032-01 | |||
Tek 155-0032-01 2.jpg|155-0032-01 | |||
Tek 155-0032-01 3.jpg|155-0032-01 | |||
155-0032-00.png|Block diagram | |||
155-0032-XX in 7A12.jpg|155-0032-00 schematic shown in the 7A12 schematic | |||
</gallery> | |||
[[Category:Tektronix-made monolithic integrated circuits]] | |||