Finding a switch mode regulator?

[lincoln]

Hello Gents,
     I'm on the Digikey / Mouser / ect design marry-go-round. I'm working on a box that is 90% digital and has a number of voltage rails. The two main rails (current wise) are 3.3 and 1.8 I'm targeting switch mode regulators. The other regs (2.5, 1.2, 1.0) are are relatively light (100 ma or less) or supply a single chip so i'm planing to use linear for them.

I am looking for a buck converter with : Iout = 1~3A, Vin > 12vdc, vout = 1.8, and has an oscillator sync input.

I'm hoping to use switching frequency 900k or above to keep the inductors small.

What do you think? Whats you favorite switching regulator?

[ZeTeX]

Hello Gents,
     I'm on the Digikey / Mouser / ect design marry-go-round. I'm working on a box that is 90% digital and has a number of voltage rails. The two main rails (current wise) are 3.3 and 1.8 I'm targeting switch mode regulators. The other regs (2.5, 1.2, 1.0) are are relatively light (100 ma or less) or supply a single chip so i'm planing to use linear for them.

I am looking for a buck converter with : Iout = 1~3A, Vin > 12vdc, vout = 1.8, and has an oscillator sync input.

I'm hoping to use switching frequency 900k or above to keep the inductors small.

What do you think? Whats you favorite switching regulator?

have you tried looking here?
http://www.linear.com/parametric/Switching_Regulator#!1646_Buck!1032_%3C=10!1033_%3E=15!1105_%3C=1.8!1034_%3E=1.8!1107_3:9!vinmin_10!vinmax_15!vout_1.8!iout_3!vout2_!iout2_!vout3_!iout3_

[lincoln]

Linear is a good go to, found two possible parts but a little on the expensive side but they tick all the other boxes.  looking at LTC3601 / ltc3621-2

Most of the parts that come up are not well distributed. If I punch in a part to findchips.com and I can't find two outfits that has more than 1k in stock, i'm nervous. For an OCXO sure I am willing to jump through hoops / deal with  small distributors /  lead times. I really don't want to do that for a voltage regulator that we are going to buy 500 / year

¯\_(?)_/¯

[Wobbegong]

RT7296DGJ8FCT-ND
http://www.digikey.com/product-detail/en/richtek-usa-inc/RT7296DGJ8F/RT7296DGJ8FCT-ND/5640533

?

[T3sl4co1l]

TPS54140, TPS54233, and similar parts in the range, would probably be a nice fit.

Tim

[radar_macgyver]

How about the LT8614? It can do 4A, operates above 1 MHz and has a sync input. I've used it to power low noise RF synthesizers with a clean-up LDO - TPS7A8101, with a reference bypass (aka "noise reduction") capacitor. Worked quite well, the 3.2 GHz synthesizer measured about -110 dBc/Hz at 1 kHz offset.

Apparently they now have an LT8640 that can do 5A as well.

[Thomas]

Go to TI and find their Webench Designer:
http://www.ti.com/lsds/ti/analog/webench/overview.page
Put in your numbers and BAM - your design is ready

[John_ITIC]

TPS54140, TPS54233, and similar parts in the range, would probably be a nice fit.

I'm using the below, which were the smallest I could find.

Switched for high power
TPS54418 (1.8V, 4A)
TPS54418 (0.9V, 4A)
TI SwitcherPro Software: http://www.ti.com/tool/switcherpro

Switches at 1 MHz (2 MHz too, if I recall correctly).

LDO for low power / lowest noise
TPS74701 (1.1V, 500mA)
TPS74701 (1.5V, 500mA)
TPS74701 (2.5V, 500mA)

Note these are all configurable so only two part numbers for all power rails.

[Jeroen3]

What quantity are you looking for?

[lincoln]

What quantity are you looking for?

500 - 1k this year, 3 to 5K next year,

Thanks for the suggestions, I'm working through the list.

[Jeroen3]

I think you're right on the edge regarding cost effectiveness of custom design.
For low quantities I always use dc/dc bricks. Saves a lot of risk and time. But is more expensive.