TDK-Lambda CUT35-5FF Rating: Excellent
Mouser CUT35-5FF product page: https://www.mouser.com/c/?q=CUT35-5FF
TDK CUT35 datasheet: https://www.mouser.com/ds/2/400/cut35-1101382.pdf
Mouser Project Manager for TDK CUT355FF power supply and mating connectors/pins: https://www.mouser.com/ProjectManager/P ... 65b59a493a
TDK-Lambda CUT35-5FF 5V 3A +/-15V 0.65A Triple-output Power Supply
The CUT35 is a mixture of TH and SMT. The 8 pin DIP switcher ICs appear to be a Lambda proprietary part.
TDK-Lambda CUT35-5FF 5V 3A +/-15V 0.65A Triple-output Power Supply
Note that there are dangerous potentially lethal line voltages on the primary side of this supply. Use caution when handling and bench-testing.
The CUT35-5FF is small measuring about 2" by 4".
One unique feature is that the bipolar output and 5V output are isolated and do not share a common ground.
The unloaded outputs measure almost exactly on-target.
The 5V is adjustable.
A minimum load is not required for start-up but it was found that a +/-15V (30V) pre-load current of 15 mA was required for low-noise operation.
If the CUT35 is started without pre-load and the load then added it remains somewhat noisy with sawtooth ripple in the 10s of millivolts.
With the 15 mA pre-load applied at startup, ripple and noise is exceptionally low <4mV P-P measured on the scope.
With a board connected having a 50 mA load I saw no issues with noise.
Measured with the HP400FL analog meter the output noise is -62 dBu (100 kHz filter) and -44 dBu (4 MHz). (-3dB points.)
The CUT35 appears to have two separate converters one for the 5V the second for the bipolar 15V.
It also has two transformers.
The bipolar supply uses a center-tapped transformer with half-wave rectification.
The 5V supply uses a single output winding and a dual diode half-wave rectifier connected in parallel.
There are 4 opto-isolators which cross the galvanic barrier.
The 5V may have one for voltage feedback and the second to detect over-current.
The second pair of optos, on the bipolar supply, along with a second convertor IC suggest voltage feedback for at least one of the channels if not both.
I measured the noise floor of the MS-II connected to the TDK CUT35-5FF and it was as quiet as when powered from the linear bench supply.
That's good enough!
