Simple 3.3 MicroSD set up

Can you help please.
I have a micro sd and an arduino both powered with 3.3 from a LDO Regulator capable of supplying 150 mA.
As I Understand things I should be able to wire the arduino SPI pins directly to the sd holder without any other regulator, resistor voltage divider or logic level shifter being needed. I am using a proven arduino on the correct pins, including the CS pin.
I am using a proven good card.
On using the SDFAT Cardinfo sketch, or any other sketch for that matter, the card is not recognised.
Am I getting something wrong?
Do I need any additional components in the MOSI,MISO,SCK or CS lines to make this work.
Any suggestion great fully received.
Thanks and regards

Gerihatrick:
Can you help please.
I have a micro sd and an arduino both powered with 3.3 from a LDO Regulator capable of supplying 150 mA.
As I Understand things I should be able to wire the arduino SPI pins directly to the sd holder without any other regulator, resistor voltage divider or logic level shifter being needed. I am using a proven arduino on the correct pins, including the CS pin.
I am using a proven good card.
On using the SDFAT Cardinfo sketch, or any other sketch for that matter, the card is not recognised.
Am I getting something wrong?
Do I need any additional components in the MOSI,MISO,SCK or CS lines to make this work.
Any suggestion great fully received.
Thanks and regards

Read the very first message in this forum. The Arduino library can only work with 'correctly' formatted cards.

Also, 150mA is marginal, Some SDCards require more.

Chuck.

The card has been formatted correctly using the Sdfat format utility.
The question I'm asking is are any addition components needed assuming that the regulator can meet the load. I have not experienced problems with a 150 mA LDO previously but I note your suggestion that it could be marginal. thanks.

Gerihatrick:
The card has been formatted correctly using the Sdfat format utility.
The question I'm asking is are any addition components needed assuming that the regulator can meet the load. I have not experienced problems with a 150 mA LDO previously but I note your suggestion that it could be marginal. thanks.

Place a capacitor on the VDD line at the SDCard connection, between 10uF and 100uF.

Some of the SDCard adapters include levelshift hardware to convert from 5v to 3.3v, If your card has this circuitry, and you are not using(supplying power to) the 5v input, the levelshift circuit may not be powered on. This would block signals from your CPU to the SDCard.

Chuck.

Thanks Chuck. There is already a cap across the sd power feed and the the card holder is connected directly to SPI pins and everything running at 3.3 volts. Have previously run this configuration on a breadboard without a problem.
I will now relook at, possible power supply voltage dips, and SPI Signal levels using a logic analyser and Nick Gammons site for guidance.
Regards

Feedback for info.
A Sparkfun MicroSD sniffer board gave me the answer.
The MicroSD holder had been soldered to the board incorrectly.
The holder has eight pins plus a couple more to the secure it to the PCB.
Of the eight it should have been connected to pin2 to pin7 for SPI connection.
It was in fact connected to pin1 to pin6.
Suffice it to say that I did not mount the holder on the board nor are you likely to encounter this problem yourself.

Like all things in life we learn a lot when things go wrong and I now know a lot more about SPI, thanks largely to Nick Gammons site, how to use a logic analyser, and that Sparkfun make a sniffer that pokes into the sdcard slot, etc ,etc.

We live and learn

Regards