Suggestion for top BJT in an high voltage cascode CCS for a source follower

Hi,

In a project I'm working on I need a source follower supplied with +40 and -140V, with a cascode of two BJT as CCS set at 6 mA.
The bottom BJT will be a 2N5551, while I'm open to suggestion for the top BJT.
Requirements are:
  1. Being able to dissipate up to 900mW on peaks (it will swing up to +10V), 450mW as average (it will be set around -55V at idle), so I would say we need to exclude TO92;
  2. Vce of at least 200V (I'd consider at least 230V for safety due to voltage fluctuations on the 180V we have as nominal);
  3. Fit a classic TO92 pcb connection (1=b 2=c 3=e) because this is how the pcb has been done;
  4. A good Hfe to improve the CCS impedance.
I've checked on mouser, and I've found some options:
  1. KSC2752Y : https://www.mouser.it/datasheet/2/308/1/KSC2752_D-1810664.pdf
    TO126, Vce 300V, Hfe 40-80, pinout fits, 0.61 €/each;
  2. TTC011B : https://www.mouser.it/datasheet/2/408/TTC011B_datasheet_en_20160209-1649840.pdf
    TO126, Vce 200V, Hfe 100-320, pinout fits, 0.64 €/each;
  3. TTC008 : https://www.mouser.it/datasheet/2/408/TTC008_datasheet_en_20140403-1916100.pdf
    New PW-Mold2, Vce 200V, Hfe 80-250, pinout fits, 0.87 €/each;
  4. TTD1409B : https://www.mouser.it/datasheet/2/408/TTD1409B_datasheet_en_20150806-1915948.pdf
    TO126, Vce 400V, Hfe 600, pinout fits, 1.62 €/each.
TTD1409B seems the best choice, do you have other suggestions?
Thanks in advance,

Kind Regards
Roberto
 
I've checked on mouser (where I'm buying other things) and both ZTX458 and ZTX558 are out of stock.
I've also tried to find on mouser some transistors for video output, but again no luck.

The TTC011B : https://www.mouser.it/datasheet/2/408/TTC011B_datasheet_en_20160209-1649840.pdf
TO126, Vce 200V, Hfe 100-320, pinout fits, 0.64 €/each;

after a light bending of the pins, seems the best option at the moment.
What do you think? Has anyone ever used it for this purpose?

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Thanks in advance
 
Osvaldo -
I tried doing a Google search for video output transistors and got a fair amount of NTE rubbish and people trying to finance their retirement with outrageous prices per device.

Zintolo -
Electronic Goldmine (a good source if you are in the USA) has at least 2 devices in their Japanese transistor inventory that are rated for chroma output service. One is in the TO-92L package, and one is TO-126. Both should have ECB pinouts. The TO-92L is capable of around 1/2W dissipation, and the TO-126 device can easily be fitted with a small heat sink.

https://theelectronicgoldmine.com/collections/japanese-transistors
 
Put a 'Tophat' thermal sink radiator on a hefty generic TO-5'er ... Digi-Key search runs fairly quick.
Pull up the Texas TI or National 'Semi' Catalog in tandem browser window and cross-reference-search multitask style.
On Semi has stuff too that is off grid NOS specs. Fairchild is my pick for Hulk TO5's. Just jury-leg the EBC<-->BCE as these trannies have sizable spread.
 
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TO-5s and associated heat sinks take a fair bit of real estate (you have the choice of the "sun crown" or a hi-rise solution that doesn't fit all that securely to the part in question). Plastic takes less room, and with a TO-126, you can get by with a smallish bit of aluminum sheet (or maybe even no heat sink at all). I'm not allergic to plastic...