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    convert 5v to 3.3v

    Hi All,

    Any one can suggest a simple circuit technique or component solution to do the following signaling requirement:

    1. 5V signal will be level-shift to 3.3V
    2. 3.3V signal will pass-thru directly without attentuation.

    Thanks.

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    5v to 3.3v converter

    Simple method is: serial resistor (few kiloohms, ie. 10kR) and diode (Schottky diode is the best) to +3.3V (A - resistor, K - +3.3V).
    arturt134



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    convert 3.3v to 5v

    Take a look at www.chipcon.com in Application Note AN021. Texas has a similar appnote also.



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    converting 5v to 3.3v

    I feel the best solution given the information would be a simple low voltage serial regulator. Watch out for current limitations of device

    Barrybear



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    5v to 3.3v conversion

    I suggest voltage level shifter



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    3.3v to 5v converter

    For interface voltage level conversation, look 74LVC series chips, it is
    also available in very small 1 gate packages ( and it is very low cost, for example Philips 74LVC1G125GW or TexasInstruments SN74LVC1G125DCKR chips in small 5 pim SC-70-5 packege, cost only
    5.1 US cents on 3K p.c.s.)

    FEATURES
    · Wide supply voltage range from 1.65 to 5.5 V
    · High noise immunity
    · Complies with JEDEC standard:
    – JESD8-7 (1.65 to 1.95 V)
    – JESD8-5 (2.3 to 2.7 V)
    – JESD8B/JESD36 (2.7 to 3.6 V).
    · ±24 mA output drive (VCC = 3.0 V)
    · CMOS low power consumption
    · Latch-up performance exceeds 250 mA
    · Direct interface with TTL levels
    · Inputs accept voltages up to 5 V
    · Multiple package options
    · ESD protection:
    HBM EIA/JESD22-A114-A exceeds 2000 V
    MM EIA/JESD22-A115-A exceeds 200 V.
    · Specified from -40 to +125 °C.

    DESCRIPTION
    The 74LVC1G125 is a high-performance, low-power,
    low-voltage, Si-gate CMOS device, superior to most
    advanced CMOS compatible TTL families.
    The input can be driven from either 3.3 or 5 V devices.
    This feature allows the use of this device in a mixed
    3.3 and 5 V environment.
    This device is fully specified for partial power-down
    applications using Ioff. The Ioff circuitry disables the output,
    preventing the damaging backflow current through the
    device when it is powered down.
    The 74LVC1G125 provides one non-inverting buffer/line
    driver with 3-state output. The 3-state output is controlled
    by the output enable input (OE). A HIGH level at pin OE
    causes the output to assume a high-impedance
    OFF-state.



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    5v 3.3v converter

    maxim and analog devices have specialized ic that assume such conversions in both directions, and availables in 1 2 4 or 8 channels.



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    5v to 3.3 v converter

    The easiest way in my opinion is taking a busswitch.
    This is nothing more than a mosfet for each signal pair. if the gate is enabled the mosfet is transparent into both directions with Tpd = 0.25ns and Ron = 5 Ohms. So high speed signals will have almost no propagation delay. Furthermore you don't have to tell the device from which direction the signal comes. (no additional logic for direction switch).

    by taking the mosfet you use certain saturation effects. when supplying the gate with 5volts and one side of the mosfet as well the output can be steered to approx 4volts. There the mosfet leaves conducting state and starts increasing Ron to some KOhms.

    So when supplying app. +4.3V to the gate +5V signals can be translated to +3V3.

    Have a look at
    http://www.idt.com/docs/AN_11.pdf.

    These busswitches come up to 4x8 bit per case (80pins).


    http://www.idt.com/products/pages/Bu...ches_AN_t.html


    hope it helps,

    aXOxOmOx



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    how to convert 5v to 3.3v

    abc

    /Warning #1 - Do not post empty messages! (klug)/



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    5v 3.3 v converter

    74lvx4245 f@irchild and 0nsemi.... Octal bidirectional level shifter



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    3.3v 5v interface

    TI have many ICs for level shifting, cross bar,... U can try SN54CBTD3384, SN74CBTD3384, 10-BIT FET BUS SWITCHES WITH LEVEL SHIFTING.
    The ’CBTD3384 devices provide ten bits of
    high-speed TTL-compatible bus switching. The
    low on-state resistance of the switches allows
    connections to be made without adding
    propagation delay. A diode to VCC is integrated on
    the die to allow for level shifting from 5-V signals
    at the device inputs to 3.3-V signals at the device
    outputs.



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    5v to 3.3v interface

    I had tried serial resistor network to lower the 5v i/o signal (eg 2k plus 3k resister) and just connect 3.3v i/o signal between 2k and 3k resister.

    5V i/o
    /
    \
    / 2K
    \
    |
    --------- 3.3V i/o
    /
    \
    / 3K
    \
    |
    GND



  13. #13
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    3.3v 5v converter

    Take a look at this application note from Philips AN10156.pdf (72k) and motorola AN2433.pdf (289k).

    Warning #1 - Files deleted. Don't upload files from the net just post link! Read forum rules before posting!



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    3.3v to 5v interface

    Quote Originally Posted by Eternauta
    Take a look at this application note from Philips AN10156.pdf (72k) and motorola AN2433.pdf (289k).
    Save Elektroda bandwith and please post links ...
    http://www.philipslogic.com/support/...df/an10156.pdf
    http://e-www.motorola.com/files/micr...ote/AN2433.pdf



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    5v 3.3v interface

    Quote Originally Posted by tsehonkit
    I had tried serial resistor network to lower the 5v i/o signal (eg 2k plus 3k resister) and just connect 3.3v i/o signal between 2k and 3k resister.

    5V i/o
    /
    \
    / 2K
    \
    |
    --------- 3.3V i/o
    /
    \
    / 3K
    \
    |
    GND
    Are you sure that this circuit wll work in all worst cases?



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    3.3v to 5v conversion

    This will cause a RC delay which will harm fast signals. You might try a comparator which has a 3 V logic out and the analog part runs on 5V or so.



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    interface 5v to 3.3v

    Quote Originally Posted by dinosaur
    Hi All,

    Any one can suggest a simple circuit technique or component solution to do the following signaling requirement:

    1. 5V signal will be level-shift to 3.3V
    2. 3.3V signal will pass-thru directly without attentuation.

    Thanks.
    Are there any "restrictions" like signal delay or number or lines?
    If you don't have an bidirctional signal, I agree to dainis reply: use 74LVC chip, otherwise you require some additional logic that controls the direction of your signal.
    Maddin



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    5v to 3.3v

    Hi

    I've personnaly used a 74LCX16652 from for bus insterfacing.
    It is supplyed by 3.3V and is 5V tolerent
    http://www.fairchildsemi.com/ds/74/74LCX16652.pdf




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    interfacing 5v to 3.3v

    Quote Originally Posted by arturt134
    Simple method is: serial resistor (few kiloohms, ie. 10kR) and diode (Schottky diode is the best) to +3.3V (A - resistor, K - +3.3V).
    the power supply should be just below 3 volts, to be precise 2.8v approx., assuming you are using a 10K resistor. I am sure it will give you, approx 3.3 volts with +5V interface, in any precision application.



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    5v 3v3 converter

    If signals are point to point simplest method is just to use 244 buffers. An LVX244 powered at 3.3V will accept the 5V inputs and convert to 3.3V, whilst an HCT244 powered at 5V will accept the 3.3V inputs and convert to 5V.



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