Timeline for rfp30n06le MOSFET not outputting current
Current License: CC BY-SA 3.0
16 events
| when toggle format | what | by | license | comment | |
|---|---|---|---|---|---|
| Dec 11, 2021 at 14:24 | answer | added | Dave X | timeline score: 0 | |
| Mar 26, 2020 at 23:01 | history | bumped | CommunityBot | This question has answers that may be good or bad; the system has marked it active so that they can be reviewed. | |
| Nov 13, 2019 at 2:03 | history | bumped | CommunityBot | This question has answers that may be good or bad; the system has marked it active so that they can be reviewed. | |
| Jul 10, 2019 at 12:03 | history | bumped | CommunityBot | This question has answers that may be good or bad; the system has marked it active so that they can be reviewed. | |
| Mar 8, 2019 at 21:03 | history | bumped | CommunityBot | This question has answers that may be good or bad; the system has marked it active so that they can be reviewed. | |
| Nov 30, 2017 at 19:12 | answer | added | Jcweaver | timeline score: 1 | |
| Nov 30, 2017 at 19:10 | comment | added | Dean Franks | Yes, that mosfet will operate at Vgs = 5V, but Rds will still be higher than at Vgs = 10V so the part will get hotter and you will deliver less power to the motor. | |
| Nov 30, 2017 at 19:07 | comment | added | Jcweaver | So you were right, i do need a higher gate-source voltage | |
| Nov 30, 2017 at 19:06 | comment | added | Dean Franks | if you are looking for maximum efficiency, you should be shooting for Vgs = 10V. The Threshold (Vth) is where the mosfet starts conducting any significant current, not where it is fully on. | |
| Nov 30, 2017 at 19:05 | comment | added | Jcweaver | @DeanFranks oh shoot, I bought amazon.com/Gikfun-Packing-RFP30N06LE-N-Channel-Arduino/dp/… which some guy commented that it has a 0-5V threshold voltage | |
| Nov 30, 2017 at 18:58 | comment | added | Jcweaver | @DeanFranks I need about 4A on the load at max torque. I notice the datasheet says that Vgs = +10, -8 and the Vgs(threshold) is min 1 and max 2. Should I actually be trying to reach Vgs rather than just try to pass the threshold? | |
| Nov 30, 2017 at 18:55 | comment | added | Dean Franks | You could also use a gate driver with a charge pump which allows your 3.3V microcontroller output to drive the gate at 9 or 10V. Note that some gate drivers with charge pump have a maximum duty cycle on the gate signal (they assume PWM) and a minimum PWM frequency. What are the current requirements of your load? | |
| Nov 30, 2017 at 18:53 | comment | added | Dean Franks | I'm guessing you are having RdsOn issues. At Vgs = 3.15V, the device is not close to fully on (saturated) and you are going to get a non-trivial voltage drop across the source and drain. You might want to switch to a lower voltage mosfet with a logic level gate (low Vth threshold voltage). | |
| Nov 30, 2017 at 18:47 | comment | added | Jcweaver | @DeanFranks gate-source voltage from the 3.3v source is 3.15v. gate-source voltage from the battery is 3.99v | |
| Nov 30, 2017 at 18:41 | comment | added | Dean Franks | Measure the actual voltage between the gate and the source of the mosfet when you are trying to turn it on and post the result. | |
| Nov 30, 2017 at 18:34 | history | asked | Jcweaver | CC BY-SA 3.0 |