PMIC for P2 boards?

Rayman

Anybody think a Power Management ICs is a good idea for P2 boards?
Is it overkill? Maybe...

I'm looking at the MAX77714 right now...

Unfortunately, most of the PMICs I've found, the above included, target a core voltage <1.8 V.
But, this one has several buck converters and we could just not use the low voltage one.

What's nice is that it also has an RTC (that doesn't need a crystal) and a WatchDog timer.

There are some simpler ones like this: TPS65053

But, I haven't found one that's a perfect fit for 1.8V core yet... Anybody know of a better option?

jmg

For 3v3 side, I like the look of the new NCP187AMT330TAG - low noise, with power good, and compact package with good thermals for heatsink vias & low price.
Soon to be stocked at DK & Mouser.
Now in stock at DK, and due 22nd Mouser.
Also in stock, as a possible '2nd BOM source' is NCV8187AMT330TAG (Automotive version 2x2 package, slightly higher price)


1V8 selection is trickier, and can depend on what matters ? :

* Do you need > 5V DC in, or is 5V/USB in OK
* Do you need integrated inductor, or is external inductor ok ?
* Do you want fine trim of VDD for power/speed trade offs ?
* is BGA ok, or is DFN/QFN preferred ?

Example: for 5.5V max in, and lowest cost/external inductor, in DFN package, I like the look of AP3441LSHE-7B
My notes say :
AP3441SHE-7B Diodes LV BUCK 2.7V~5.5V 0.6V~5.5V 3A 1MHz PGood -40°C ~ 85°C (TA) 8.2 °C/W 8-VFDFN U-DFN2020-8 2x2mm 72mΩ 52mΩ << NEW low cost $0.14603/3k

or, if i2c and pin-select PSU flexibility are needed, this OnSemi part looks interesting, ( 1.10 VSEL should be ok for P2 RAM retention ?)
NCV6357A 3.0 × 4.0 mm / 0.5 mm Pitch DFN 14 Package 5A 39 <60 mΩ 32 <45 mΩ 76c/3k
• Programmable Output Voltage: 0.6 V to 3.3 V in 12.5 mV Steps 1.8V default, 1.10V VSEL in 2 order codes : NCV6357A NCV6357C
• Up to 2.4 MHz Switching Frequency with On Chip Oscillator
• I2C Control Interface with Interrupt and Dynamic Voltage Scaling Support

Rayman

I think I've decided to try out the TPS650532...

I can actually use the 1.5 V regulator to supply power to the RTC on an FTDI chip...

jmg

Rayman wrote: »

I think I've decided to try out the TPS650532...

Could be a bit light on current, with 250 mΩ typ PFETs?

Rayman

Right now, I'm doing everything with USB power only, 500 mA max. This thing has 1 A for 3.3 V and 1 A for 1.8 V and 2 LDOs for an extra 600 mA of 3.3 V.
Seems like plenty to me...

Rayman

Just noticed datasheet says you can use the output of one regulator to enable another, letting you stagger turn on of the supplies.
I think usually you want the core to get power before the I/O...