This thread has been locked.

If you have a related question, please click the "Ask a related question" button in the top right corner. The newly created question will be automatically linked to this question.

LM5175和LM5176的区别

Other Parts Discussed in Thread: LM5175, LM5176

LM5175和LM5176是PIN to PIN 兼容的,这两款产品在性能参数和稳定性上有什么区别吗?从规格书上看不出多大的差别

  • Parametrics

    LM5175

    LM5176

    Topology

    Buck/Boost

    Buck/Boost

    Vin(Max)(V)

    42

    55

    Vin(Min)(V)

    3.5

    4

    Iq(Typ)(mA)

    1.65

    2

    Features

    Adjustable Current Limit,Enable,Frequency Synchronization,Power Good,Pre-Bias Start-Up,Synchronous Rectification,UVLO Adjustable

    Adjustable Current Limit,Enable,Frequency Synchronization,Power Good,Pre-Bias Start-Up,Synchronous Rectification,UVLO Adjustable

  • Hi
    前者可利用脉冲跳跃来选择连续导通模式 (CCM) 或断续导通模式 (DCM),后者是强制连续导通模式 (FCCM)
    其次就是输入电压范围不同。

  • you can replace the LM5175 with the LM5176 but remember to change the RT resistor to remain the same switching frequency. Please refer the the LM5176 datasheet for the new RT resistor values.

    The main differences between the two parts may not be much visible to you. The LM5176 included a voltage clamp protection on the BOOT pins which the LM5175 does not have and may be needed to add externally when employing fast MOSFETs like the TI NexFETs.
  • 你好,

    如果是新设计,建议使用LM5176,对MOSFET不敏感,谢谢。
  • v差别不大,76 兼容性更好

  • MODE配置上方式和RT/SYNC设置上有所区别。
  • 我现在采用LM5175做的电源,主要工作在Buck模式,8~24V转4.5V。

    有这样一个问题:电源正常工作一段时间后,可能是几分钟或几小时。SW2波形就不正常了,且不再恢复正常。正常SW2大约每1ms下拉一次,给Cboot2充电。不正常时,SW2每个周期都会下拉一次,示波器看见Cboot2电容电压下降很快,需要每个周期补充能量。

    断电万用表测得SW2和Boot2之间电阻只有100多欧姆。取掉Cboot、充电Diode,测得的阻值仍为100多欧姆,应该是LM5175本身损坏。这种情况下,输出正常。SW1波形正常,但LM5175很烫。

  • 您好:

    我现在采用LM5175做的电源,主要工作在Buck模式,8~24V转4.5V。
    有这样一个问题:电源正常工作一段时间后,可能是几分钟或几小时。SW2波形就不正常了,且不再恢复正常。正常SW2大约每1ms下拉一次,给Cboot2充电。不正常时,SW2每个周期都会下拉一次,示波器看见Cboot2电容电压下降很快,需要每个周期补充能量。

    断电万用表测得SW2和Boot2之间电阻只有100多欧姆。取掉Cboot、充电Diode,测得的阻值仍为100多欧姆,应该是LM5175本身损坏。这种情况下,输出正常。SW1波形正常,但LM5175很烫。
    现在4个开关选用的MOS都是FDMC86102L,其Ciss:999pF,Qg:7.3~15nC。请问是否MOS有问题?