coltoff@PRC.Unisys.COM (Joel Coltoff) (01/07/88)
The January (I think) issue of Radio-Electronics in the Ask R-E section
has a circuit for monitoring a car battery voltage. I was trying to
understand how the sucker works but get stuck when it comes to the
1N470 zener diode. I can't find this past listed anywhere. Is this a
mistake. The original schematic came from the December 1976 Electronic
Engineering which our library, of course, doesn't have anymore. Is the
1N470 an obsolete part? I sure would appreciate it if someone could
tell me the voltage of this diode.
Thanks in advance,
- Joel Coltoff
{sdcrdcf,psuvax1}!burdvax!coltoff (UUCP)
coltoff@burdvax.prc.unisys.com (ARPA)larry@kitty.UUCP (Larry Lippman) (01/07/88)
In article <5188@burdvax.PRC.Unisys.COM>, coltoff@PRC.Unisys.COM (Joel Coltoff) writes: > The January (I think) issue of Radio-Electronics in the Ask R-E section > has a circuit for monitoring a car battery voltage. I was trying to > understand how the sucker works but get stuck when it comes to the > 1N470 zener diode. I can't find this past listed anywhere. Is this a > mistake. The original schematic came from the December 1976 Electronic > Engineering which our library, of course, doesn't have anymore. Is the > 1N470 an obsolete part? I sure would appreciate it if someone could > tell me the voltage of this diode. The 1N470 is a zener diode rated at 7.1 volts @ .250 watts. The tolerance is +/- 10%. Today, 7.1 volts is an unusual zener voltage. You might consider using a common 1N4736A (6.8 volts) or 1N4737A (7.5 volts); these diodes are rated at 1.0 watts. While this zener series does not offer a 7.1 volt part, one or the other of the above values is probably good enough since I have specified numbers with a 5% tolerance. <> Larry Lippman @ Recognition Research Corp., Clarence, New York <> UUCP: {allegra|ames|boulder|decvax|rutgers|watmath}!sunybcs!kitty!larry <> VOICE: 716/688-1231 {hplabs|ihnp4|mtune|utzoo|uunet}!/ <> FAX: 716/741-9635 {G1,G2,G3 modes} "Have you hugged your cat today?"
rep@genrad.UUCP (Pete Peterson) (01/07/88)
In article <5188@burdvax.PRC.Unisys.COM> coltoff@PRC.Unisys.COM (Joel Coltoff) writes:
Is the 1N470 an obsolete part? I sure would appreciate it if someone could
tell me the voltage of this diode.
I can't find the 1N470 in any of my current data books or catalogs, so I
assume it is indeed obsolete.
My hoary Motorola "The Semiconductor Data Book" indicates that it's 6.8
volt nominal Vz, 200 mw. Min and max Vz are 6.2 and 8.0 respectively; the
1N470A is a 5% tolerance version whilst the 1N470B is 1%. Motorola lists
the 1N5235B as a "similar" replacement. Note that the shiny new Motorola
books just give the suggested replacement without giving the specs on the
original part --- there are virtues to being a pack rat.
pete peterson
{decvax,linus,wjh12,mit-eddie,masscomp}!genrad!repmjk@edison.GE.COM (Mark Kocher) (01/08/88)
In article <5188@burdvax.PRC.Unisys.COM>, coltoff@PRC.Unisys.COM (Joel Coltoff) writes: > 1N470 an obsolete part? I sure would appreciate it if someone could > tell me the voltage of this diode. The Motorola rectifier data book lists a 1N5235B as a "similar replacement" for the 1N470. It's a 500 mW, 6.8V zener in a glass package. My guess is that unless the application is an oddball, any 6.8V zener will do.