155-0078-00

The 155-0078-xx (chip designation M84) is a Tek-made broadband vertical amplifier integrated circuit in a minipac package. The input and output are differential. The 155-0078 was designed by John Addis for the 485 scope ^{(Note 1)}, which uses no less than 18 of these chips in various grades.

The last two digits of the 155-0078-xx part number are determined by a selection process after manufacture. These characteristics are summarized below:

SUFFIX	SPEED	DC CHARACTERISTICS	REPLACEABLE BY
00	Fast	Best	----
01	Fast	Third best	-03,-00
02	Fast	Most relaxed	-01,-03,-00
03	Fast	Second best	-00
04	Slow	Same as -00	-00
05	Slow	Same as -01	-03,-00,-07,-04
06	Slow	Same as -02	-01,-03,-00,-05,-07,-04
07	Slow	Same as -03	-00,-04
10	Fast	Best	----
11	Fast	Third best	-13,-10
12	Fast	Most relaxed	-11,-13,-10
13	Fast	Second best	-10
Sometimes an instrument will contain a better grade of part than called for in the manual. The manual should be consulted for the correct replacement type.

Furthermore, it also comes in 14-pin DIP, as 155-0273-00 and 155-0274-00 (slower grade).

Pictures

• 

  Excerpt from 067-0587-01 schematic, showing application of 155-0078-00.

• 

  155-0078-01 amplifiers in 7A26. Note symmetric layout.

Used in

• 475 (U140, U240, U450)
• 485
• 7834, 7844 (U415,U515)
• 7854 (A13U520,A13U590,A13U620,A13U680)
• 7904, 7903 (U5510,U5530,U5550,U5610,U5630,U5650)
• 7A16A, 7A16P
• 7A24, 7A26 (U1350,U1450,U1550,U1750,U2350,U2450,U2550,U2750)
• 067-0587-01
• PG502 (U360, -06)

Notes

• Note 1: See John Addis quote in 7A11 article