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PCI 2050B powersupply design/ vccp and vcc

Basil Alias
Prodigy 90 points

Hi,

              What is the current requirement for vcc and vccp supply. I will be using 33MHz in both primary and secondary side. In the datasheet, it is mentioned that vccp has to be powered on first then vcc. Is it a mandatory condition? Can I give both together ( From same supply rail)

 

 

  • 0
    TI__Mastermind 27890 points

    Hello Basil,

    Power numbers below:

    Measurements were taken at the noted voltages.
                                                                      Icc (typ)  Icc (max)  Ipccp(typ)  Isccp(typ)
    Primary Bus: 33 MHz / Secondary Bus: 33 MHz / Power State D0/D1:  37 mA      169 mA     10 uA       0 uA
    Primary Bus: 33 MHz / Secondary Bus: 33 MHz / Power State D2/D3:  12.4 mA    169 mA     10 uA       0 uA
    Primary Bus: 66 MHz / Secondary Bus: 33 MHz / Power State D0/D1:  43.5 mA    189 mA     27 uA       0 uA
    Primary Bus: 66 MHz / Secondary Bus: 33 MHz / Power State D2/D3:  20.7 mA    189 mA     27 uA       0 uA
    Primary Bus: 66 MHz / Secondary Bus: 66 MHz / Power State D0/D1:  61 mA      234 mA     27 uA       17 uA
    Primary Bus: 66 MHz / Secondary Bus: 66 MHz / Power State D2/D3:  20.5 mA    234 mA     27 uA       0 uA
    Where: Icc @ Vcc = 3.3V; Ipccp @ P_Vccp = 5.0V; Isccp @ S_Vccp = 3.3V
    * Typical measurements above were taken with a 66 MHz capable SCSI adapter and hard drive on the secondary bus. Maximum measurements were taken using bus exercisers toggling the address/data lines between 0 an 1. A measurement of 0 means the current draw is negligible.

                                                                   Total Icc (typ)
    Primary Bus: 33 MHz / Secondary Bus: 33 MHz / Power State D0:  40 mA (no load) / 90 mA (two loads on 2nd bus)
    Primary Bus: 66 MHz / Secondary Bus: 66 MHz / Power State D0:  88 mA (no load) / 117 mA (two loads on 2nd bus)
    Where: Icc @ Vcc = 3.3V; Ipccp @ P_Vccp = 5.0V; Isccp @ S_Vccp = 5.0V

                                                                  Total Icc (typ)
    Primary Bus: 33 MHz / Secondary Bus: 33 MHz / Power State D0:  68.3 mA (no load)
    Where: Icc @ Vcc = 3.3V; Ipccp @ P_Vccp = 3.30V; Isccp @ S_Vccp = 5.0V

     

    As for power sequencing, assuming this is a 3.3V only solution, there should be no issue powering both VCC and VCCP from the same rail.

     

    Best,

    DK