Post by thread:[EE]: Any ways or devices to work as a relay

Hi All, I need to turn ON/OFF a small d.c. motor regularly, the d.c. voltage as applied on the motor is 1.5 V, while the current throwing through is less than 80mA. As the whole thing will be driven by batteries, I want all the power to go to the motor instead of the mechanism to turn it ON/OFF. Hence I would avoid using a relay since the current drawn by the relay coil will be quite big. Is there any power-budgetary ways to turn ON/OFF my motor? Thanks in advance! Randy

On 10/28/05, John Waters <spam_OUTjohn_fm_watersTakeThisOuThotmail.com> wrote: > I need to turn ON/OFF a small d.c. motor regularly, the d.c. voltage as > applied on the motor is 1.5 V, while the current throwing through is less > than 80mA. As the whole thing will be driven by batteries, I want all the > power to go to the motor instead of the mechanism to turn it ON/OFF. Hence I > would avoid using a relay since the current drawn by the relay coil will be > quite big. Is there any power-budgetary ways to turn ON/OFF my motor? You could use a normally closed relay, then the relay would only be taking power when the motor isn't. Josh -- A common mistake that people make when trying to design something completely foolproof is to underestimate the ingenuity of complete fools. -Douglas Adams

On 10/28/05, John Waters <.....john_fm_watersKILLspam@spam@hotmail.com> wrote: > Hi All, > > I need to turn ON/OFF a small d.c. motor regularly, the d.c. voltage as > applied on the motor is 1.5 V, while the current throwing through is less > than 80mA. As the whole thing will be driven by batteries, I want all the > power to go to the motor instead of the mechanism to turn it ON/OFF. Hence I > would avoid using a relay since the current drawn by the relay coil will be > quite big. Is there any power-budgetary ways to turn ON/OFF my motor? > > Thanks in advance! > > Randy > Transistor. Regards, Mark markrages@gmail -- You think that it is a secret, but it never has been one. - fortune cookie

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Mark Rages wrote: >> I need to turn ON/OFF a small d.c. motor regularly, the d.c. voltage as >> applied on the motor is 1.5 V, while the current throwing through is >> less than 80mA. As the whole thing will be driven by batteries, [...] >> Is there any power-budgetary ways to turn ON/OFF my motor? > > Transistor. Possibly better a MOSFET. Or a bistable relay, if you like relays and don't switch too fast or too often. Gerhard

You can use tiny solid state relays that come in DIP 8 or DIP 6 packages. They draw little current. On 10/28/05, John Waters <.....john_fm_watersKILLspam.....hotmail.com> wrote: > I need to turn ON/OFF a small d.c. motor regularly, the d.c. voltage as > applied on the motor is 1.5 V, while the current throwing through is less > than 80mA. As the whole thing will be driven by batteries, I want all the > power to go to the motor instead of the mechanism to turn it ON/OFF. Hence I > would avoid using a relay since the current drawn by the relay coil will be > quite big. Is there any power-budgetary ways to turn ON/OFF my motor? -- Chetan Bhargava Web: http://www.bhargavaz.net Blog: http://microz.blogspot.com