laterally diffused field effect transistors

• Aug 4, 2004

• #1

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kukurigu

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dmos transistor

Hello,

What is DMOS transistor? What are its applications, advantages and drawbacks?
Any info is welcome! An article in PDF format would be perfect!

 

• Aug 5, 2004

• #2

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Hughes

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what is dmos

Double-diffusion MOS or Double-implanted MOS.
It is used in high-voltage applications.

 

• Aug 6, 2004

• #3

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rajesh13

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dmos power transistor

kukurigu said:

Hello,

What is DMOS transistor? What are its applications, advantages and drawbacks?
Any info is welcome! An article in PDF format would be perfect!

Click to expand...

Please find info. in the attached file.
Basically the idea in case of DMOS is to add a series resistor incase of normal cmos transitor so that a higher Vds volatge can be applied.

 

Attachments

• ldmos.pdf

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• Aug 8, 2004

• #4

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goodboy_pl

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tsmc bcd process

DDMOS: Double Diffusion MOS
the idea behind it is a series connected high voltage jfet to drain pin of a mosfet (it is intrinsic!) to increase Vds breakdown voltage also since current path is vertical, lower Rds(on) and lower gate capacitor is possible in comparison with conventional planar MOSFET. they are used in switching power supplies up to several kilo-watts and RF amplifiers up to 500 MHz with more than 300 watts!

LDMOS: lateral Difusion MOS
their concept is very similar to DDMOS with the ability of integration in ICs and with higher freq. response in comparison with DDMOS.
Their applications are powr amplifiers up to 2GHz and up to 150 Watt, and integrated inteligent IC for switching applications like motor cotroller/drivers, HVIC IGT Drivers, and even fully integrated SMPS!

BEST!

 

• Aug 9, 2004

• #5

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staric

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drain extended mos

What I know the DMOS is used in high-voltage application. And most of them is asymmetry structure. The drain can afford high-voltage. But Vgs in some of them is still low-voltage. Most of them are used in output stage or power device.

 

• Aug 10, 2004

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rajesh13

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dmos transistor

staric said:

What I know the DMOS is used in high-voltage application. And most of them is asymmetry structure. The drain can afford high-voltage. But Vgs in some of them is still low-voltage. Most of them are used in output stage or power device.

Click to expand...

Yeah most of them are off low Vgs. But since there is no overlap between Gate & drain. so Vgd is not a problem in this case.

 

• Aug 10, 2004

• #7

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andy2000a

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what is a dmos transistor?

Hi
How to design Smart power IC ?? someone told me Dmos is easy
combine with CMOS process ..

tsmc/umc Hi-V process only 40v and it is low Volt dmos
another friend said DMOS is Hi-V low Power .. like IR Co.
really power IC need "BCD process" but I don't know they use DMOS or Vmos .. in BCD ..

as I know , tsmc /umc or vanguard DMOS still low volt on DMOS ..

 

• Aug 10, 2004

• #8

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goodboy_pl

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ldmos high voltage chartered

for HV design u must use HV process not main stream low voltage CMOS procss from tsmc orothers.
some FABs like AMS provide high voltage process with LDMOS (not DMOS!) up to 80 volt suitable for automotive or power managment/driver ICs.
Power integrations uses CMOS/LDMOS for their TOPSwitch and delivers up to 200 watt with an integrated 700 volt power LDMOS!
It is possible to integrate control ckt. in DMOS process also; VIPer from ST use this technique and delivers up to 100 watt!
large companies like IR and ST use their own customized process.
Powerintegration is afabless company but they have developed their own process (CMOS/LDMOS) and OKI japan fabricates for them!


PS:see also
https://www.amazon.com/exec/obidos/aSIN/079238234X/memsclearinghous/102-8972600-6474565

BEST!

 

• Aug 11, 2004

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Colbhaidh

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tsmc ldmos

LDMOS is offered by TSMC and Chartered SEMI but only for LCD applications so max 40V or +/- 20V. Anything higher than this requires a very large N- drift region for the depletion zone and is not readily integrated with standard CMOS processes. (Become vertical rather than lateral). Higher than 40V will require off-chip.
Motorola and IRF have SmartMOS processes capable of doing this but I do not have any info on them.

 

• Aug 18, 2004

• #10

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andy2000a

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umc ldmos breakdown

I reading a Book smart power IC tech & app /
B Murari F.Bertotti GA Vignola
/ Springer


this Book talk about BCD process and some Hi-V device in BCD
1. Hi V P_channel Mos
2. LLD (low leakage diode ) -- LL Diode & BC_diode
3. Lateral DMOS
4. vertial DMOS

but I have some question is

what is difference VDMOS/ power U(V)_mos / LIGBT /LDMOS
as I know power Mos is vertial but
no isolation (can not merge with CMOS) , and have large current > 5A

LDMOS = Hi-V low current (current < 5A)
LVMOS = Hi-V Hi-cuurent
L_IGBT = Hi current density > DMOS but have latch problem
UMOS = Hi-V Hi current

 

• Oct 9, 2004

• #11

L

layes

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demos ldmos

1,high voltage
2,big current
3, low resistor

 

• Oct 9, 2004

• #12

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Bin_Wang

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dmos-transistor

DMOS used in high voltage application and with low
Rdson , you can found it in BCD process provided by Sanyo and SIMBCD.

 

• Nov 10, 2004

• #13

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mylihua

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edmos vs ldmos and pdf

what is dmos transitor,and ddmos transitor? what is ther layout ?

 

• Nov 10, 2004

• #14

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cetc1525

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difference between ldmos and demos

dmos use as a high voltage device .

 

• Nov 11, 2004

• #15

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electronrancher

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extended drain mos, applications

one of the main differences you will see between mos & dmos is that there is only a small portion of diffusion to invert, not whole gate length like in standard SCMOS - most of gate overlaps majority region.

 

• Jul 23, 2006

• #16

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cloudliu

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bcd mos tsmc

It's useful for me,thank you!

 

• Aug 8, 2006

• #17

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ukint

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what is dmos transistor

DeMOS stands for drain extended mos.IF u happen to see the layout you can find that there are two drains shorted as one and one source.This helps in draining or taking in huge voltages.For eg.A 1.8v DEMOS can take upto 3.3V.

find the doc attached.Could be useful!!!!!

 

• Aug 10, 2006

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tkyoo0220

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design dmos trasistor

Anyone can explain about this ?

I am dying to know about it. Any difference between LDMOS and DeMOS ?

 

• Aug 13, 2006

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cloudius

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advantage demos drain extended

good post

 

• Aug 28, 2006

• #20

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tkyoo0220

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ldmos isolation

DMOS and DeMOS is totally different. One is double diffused MOS and the other is Drain extended MOS.

I really want to get more info about DeMOS, not DMOS.