Digital Power

5 V out

Lukas Holm — Fri, 18 Sep 2009 07:31:25 GMT

Hi,

I'm designing a CPU/FPGA board with multiple voltage rails, ranging from 0.9 V to 5 V. I'm thinking about using the UDC9240 controller and Powertrain modules. However, the Powertrain modules can't supply 5 V out. How should I solve the 5 V out power supply? I would like the 5 V rail to be controlled by the UDC9240 also, so that I can sequence and monitor it through the same controller interface. (Input voltage is 12 V.)

Thanks,

Lukas

UCD 9240

Gerhard Kreuzer — Fri, 04 Sep 2009 17:23:36 GMT

Hi,

need a controller to mamage a constant current source, based on a SEPIC topology. The current should be programmable between 0.5mA and 500mA, with a open loop voltage of about 500V. Can I use the UDC9240 to manage a SEPIC topology, because the transfer function of the power stage is of 4th order. Can I use the UDC9240 to make a constant current source with max. voltage limitation instead of making a constant voltage source with max. current limitation as described in the data sheet?

Thanks for helping.

With best regrads

DI Gerhard Kreuzer

surge current

mani — Tue, 18 Aug 2009 09:23:05 GMT

i m a student.i have some problem related with power supply.i m using tps40060 buck regulator for vin 48vdc ,ouput 5vdc @ 6A.in example surge current is given for 3.3vdc output .but how can i calculate with this parameter.kindly please also how calculate output ripple voltage.?

thanx

Need Schematic for PTH08D110 Module

Elden Crom — Tue, 27 Jan 2009 18:07:57 GMT

--or the spec for the module

The PTH08D110 is a part on the 'EightChBuck-DCDC-SCH.pdf' from sprc678 (In the BOM for the TMDSDCDC8KIT, it's listed as 'TI to provide'). But I don't know what's inside. And google and the TI site don't recognize the part number. My questions are,

a) How is the current measured, can it measure negative? Is it across the highside or from the lowside fet?

b) What happens when the Inhibit is driven low.

c) What is SRE?

I would like to use this dev kit to drive a three phase sensorless motor. To do so I need to allow one phase to float, ie both highside and lowside fett need to be off, so that I can read the voltage generated by that winding. Thus, I think I need to wire the Inhibt to a GPIO, assuming that I won't blow anything up.

I think I found My answer....the part number in the schematic is wrong it's actually a PTD08A010W.

ucd9240 PAGE command issue and can not produce any voltage output

Changling WU — Sat, 18 Jul 2009 06:50:00 GMT

Dear sirs,

Every time I write parameter to the register of PAGE, the ucd9240 will return me “connection refused”. I can’t change the rail, so I can only use the page 0, rail 1. Is the page command has something special?

BTW, we don’t have the TI standard USB interface adapter.so we comunication ucd9240 with ARM (s3c2440 ,the pmbus comunication driver design by ourselfs)

Two issues:

(1) I enabled the function of PEC, but the PAGE command still does not work. From scope observation, I found that issuing other commands can produce the PEC field, but the PAGE command can NOT, please refer to the attached images for details.

It seems that when issuing PAGE command, 9240 receives the DATA field and then immediately decides that the received data is invalid and responds with NACK. Thus the PEC field has no chance to be delivered.

(2) Although the spec describes that after reset, all status bits of 9240 will be cleared. But experimentally we found that this is not true. In particular, the STATUS_BYTE and the STATUS WORD always read as 0x40.and we have powered to the VIN by12volt ,and has read the correct value in READ_VIN register(0x88h)

We are very confused on these, and hope you can help us out.

UCD9240EVM

Jon Woodhead — Thu, 21 May 2009 09:01:47 GMT

Hi,

I recently attended one of Texas' Power Supply Design Seminars and was interested by the digital control topic and particularly the options made available with PMBus and Fusion Desginer. The videos for the UCD9240 mention a development module but i can't find any information on ordering this anywhere on the web site. Is this going to be available any time soon or are there any other predesigned options for connecting this to a PC for exploring the possiblilties available?

Regards,

Jon

about Vin range of ucd9240 support

Changling WU — Fri, 05 Jun 2009 03:40:53 GMT

dear sir,

Can I use 24V as VIN to produce VOUT smaller than 24 V? I Refer to "UCD92XX digital pwm system controller PMBUScommand reference.pdf ",in page 35, The maximum value of 35H (VIN_ON) and 36H (VIN_OFF) can reach 31.9688V , but in page 36 The limit value of 55 H (VIN_ OV _ FAULT _ LIMIT) can only reach 15.984v , that is to say when VIN reach to 15.984V, the VIN _ OV _ FAULT _ LIMIT situation will take place.How much maxmum value of VIN does the ucd9240 support ? thanks in advance!

best regards!

changling