Sort of a dual MPSA18.
--
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
Why did they leave out how closely matched they are? I assume they are prettydarn close, being on the same die....
Cheers
Pretty close. Pity it's not a monolithic dual!
Cheers
Phil Hobbs
-- Dr Philip C D Hobbs Principal Consultant ElectroOptical Innovations LLC Optics, Electro-optics, Photonics, Analog Electronics
160 North State Road #203 Briarcliff Manor NY 10510 USA +1 845 480 2058hobbs at electrooptical dot net
Plausible assumption. Not giving a substrate connection, I'd assume different die. Did I miss this information somewhere?
They are most likely not on the same die, but probably two transistors off the same wafer. Which means they won't be very isothermal if they dissipate different amounts of power. Like this NEC dual:
These are only 5 cents in quantity! Beta runs around 1000. I was thinking one of these would be good in Phil's photodiode circuit.
They DO NOT say anything like on the same die. ALL DUALS are made with separate die; matching typically is from masking repeatability making for (perhaps) a few millivolts,like in the good old UA709 where the pair is on the same die.
Exactly!
Analog Devices still makes some monolithic duals.
And other MAT devices. MAT02 03, 04, etc.
Even quads!
Hopefully the good old Super Matched pair? Part numbers please.
Intersil too:
Try analog.com.
The Intersil HFA series are monolithic. They're loosely based on the CA3046 et al., with six BJTs on the die and various metallization options. They're pretty nice parts actually, except for fairly depressingly high R_bb' and R_ee'.
I suspect they did that on purpose to help keep them from oscillating, but it's annoying in applications.
Cheers
Phil Hobbs
I think those transistors are scattered around the die (not cleverly interleaved) so aren't super-isothermal.
The die size is ~40mil x 40mil, plus they're die bonded to a metal pad, so they're pretty tightly coupled thermally.
Keep the Vce's and Ic's close (*), and they'll match.
(*) Wrap OpAmps around them... Hobbs, Think Stheno. ...Jim Thompson
Thanks!
Crap. Different die, proven by Vos in 6mV region. Even the typical uA709 was better.
Check; JW gave some excellent and real examples.
Right, they're in two rows of three, just like the CA3046. I have a die picture someplace.
Cheers
Phil Hobbs
I'm wrapping PNP series-shunt feedback loops around them, among other things. Works great.
Cheers
Phil Hobbs
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