New Contributor对于PDN设计的时候，对应的Noise门限按照什么来？是DS中的Min和Max来（AC Tolerance + VR Accuracy）？Ripple？AC Transient？还是Ripple+AC Transient？但是对于Transceiver又有Ripple、AC Transient，非Transceiver的是Ripple和AC Transient合并在一起说明的。对应的频率范围是考虑哪个区间的？100KHz~2MHz吗?
对应的IR Drop的判定是什么？DS中的Min和Max吗？
Regular ContributorHello,
May I know what is your question? I will try to answer.
regards,
Farabi
Regular ContributorEnglish translate:
When designing PDN, what is the corresponding Noise threshold? Is Min and Max coming in DS (AC Tolerance + VR Accuracy)? Ripple? AC Transient? Or Ripple+AC Transient? But for Transceiver, there are Ripple and AC Transient. For non-Transceiver, Ripple and AC Transient are combined together. Which interval is considered for the corresponding frequency range? 100KHz~2MHz?
What is the corresponding determination of IR Drop? Min and Max in DS?
Regular ContributorQ1: When designing PDN, what is the corresponding Noise threshold? Is Min and Max coming in DS (AC Tolerance + VR Accuracy)? Ripple? AC Transient? Or Ripple+AC Transient?
<ANS> recommended Noise threshold = Voltage Regulator ripple allowance + AC Transient
Q2: But for Transceiver, there are Ripple and AC Transient. For non-Transceiver, Ripple and AC Transient are combined together.
<ANS> Yes, correct. Commonly, Transceiver's Voltage Regulator requirement is higher ~1% ripple. The extra margin is transfered to AC transient to make sure the Power delivery can cover the current surge during transceiver's high frequency transitions in user mode.
Q3: Which interval is considered for the corresponding frequency range? 100KHz~2MHz?
<ANS> ftarget should be covering 100KHz to 10MHz. More than that the physical capacitors will not able to cover and this frequency range will be covered by on-die decoupling capacitors.
Q4: What is the corresponding determination of IR Drop? Min and Max in DS?
<ANS> please refer to Table 13 of AN910 for the recommended transient and step load spec. For IR drop you can refer to min and max in DS.
regards,
Farabi
