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LMZ31704: LMZ, connect INH together ?

Part Number: LMZ31704
Other Parts Discussed in Thread: LMZ22010, LMZ31520, LMZ30602, , LMZ31707

Dear Sirs,

For a FPGA  power supplies sequencing, I need to cascade these supplies:

LMZ22010 (POK) =>  | (INH) LMZ31520 (POK) |

| (INH) LMZ31704 (POK) | => | (INH) LMZ30602 (POK) |

                                                | (INH) LMZ31704 (POK) | => | (INH) LMZ31707 (POK) |

                                                                                                                                    | (INH) LMZ31704 (POK) |

My question is : Can I connect the INH signals of 2 DCDC converters together in order to control them with one PGOOD signal which is Open Collector ?

I need to connect the INH signals of these DCDCs together:

LMZ31520 & LMZ31704

LMZ30602 & LMZ31704

LMZ31707 & LMZ31704

For the LMZ30602, I read that I cannot connect an external pull up resistor to INH. If I connect the INH pin of the LMZ30602 to the one of the LMZ31704, will I have problem with the current source inside the LMZ31704 ?

Best Regards,

Stoffels K.

  • The POK => INH sequencing you show above should work as intended.

    However, without knowing the input voltages or if you have any UVLO resistors tied to the INH pins, I can't say for sure.

    Can you let me know what input voltages you are using for each device and if you are setting the UVLO externally for each device? You can send me this detail offline at

    Thanks, Jason