MAX5946LETX+T【PDF 16/23 页】IC CNTRLR PCI EXP DL 36TQFN

收藏本站

您好，
买卖IC网欢迎您。
请登录
免费注册

买卖IC网

Sheet目录43

12页 13页 14页 15页 [16页]17页 18页 19页 20页

12V and 3.3V Outputs Normal Operation

The MAX5946 monitors and actively limits the current of

the 12V and 3.3V outputs after the startup period. Each

output has its own overcurrent threshold. If any of the

monitored output currents rise above the overcurrent

threshold for a period t

FAULT

, FAULT_ asserts and the

controller disengages both the 12V and 3.3V outputs for

the particular slot (see the Fault Management section).

3.3V Auxiliary Output Normal Operation

The auxiliary output current is internally monitored and

actively limited to the maximum current-limit value. An

overcurrent fault condition occurs when the output

current exceeds the overcurrent threshold for longer

then t

FAULT

. A fault on an auxiliary channel causes all

supplies of the affected channel to be disabled after a

programmable time period t

FAULT

(see the Fault

Management section).

Power-Good (PPWWRRGGDD__)

Power-good (PWRGD_) is an open-drain output that

pulls low a time (t

POR_HL

) after all of the outputs of the

respective slot are fully on. All outputs are considered

fully on when 3.3G_ has risen to V

PGTH3.3

, 12G_ has

risen to V

PGTH12

, and V

3.3AUXO_

is less then

PGTH3.3AUX

. t

POR_HL

is adjustable from 2.5ms to

1.5s by connecting a resistor from PORADJ to GND.

See the Setting the Power-On-Reset Timeout Period

POR

) section.

Thermal Shutdown

When the die temperature goes above (T

) +150癈, an

overtemperature fault occurs and the MAX5946 shuts

down all outputs. The device waits for the junction temper-

ature to decrease below T

- Hysteresis before entering

fault management (see the Fault Management section).

Dual PCI Express, Hot-Plug

Controller

16 ______________________________________________________________________________________

ON_,TH

ON_, AUXON_

PWRGD_

FAULT_

12G_, 3.3G_

12VO_, 3.3VO_

3.3VAUXO_

PGTH12

PGTH3.3

PGTH3.3AUX

3.3AUXIN

RISING

EDGE

PWRGD_ IS PULLED UP TO 3.3.

FAULT_ IS PULLED UP TO 3.3AUXIN.

POR_HL

Figure 2. Power-Up Timing, No Fault

FAULT_

3.3VAUXIN

RISING

EDGE

PWRGD_ IS PULLED UP TO 3.3VAUXO_.

FAULT_ IS PULLED UP TO 3.3VAUXIN.

A FAULT ON THE 3.3V OUTPUT OR 3.3VAUXO_ OUTPUT PRODUCES SIMILAR RESULTS.

ON_,TH

ON_

2 x t

FAULT

PWRGD_

12G_

12V OUTPUT

CURRENT

3.3VAUXO_

12ILIM,TH

SENSE

Figure 3. 12V Power-Up Timing (Turn-On into Output

Overcurrent/Short Circuit)

FAULT_

PWRGD_ IS PULLED UP TO 3.3VAUXO_.

FAULT_ IS PULLED UP TO 3.3VAUXIN.

A FAULT ON THE 3.3V OUTPUT OR 3.3VAUXO_ OUTPUT PRODUCES SIMILAR RESULTS.

FAULT

PWRGD_

12G_

12V OUTPUT

CURRENT

12ILIM,TH

SENSE

Figure 4. 12 Output Overcurrent/Short Circuit During Normal

Operation

发布紧急采购，3分钟左右您将得到回复。

采购需求

(若只采购一条型号，填写一行即可)

*型号	*数量	厂商	批号	封装

添加更多采购

采购需求

发布成功！您可以继续发布采购。也可以进入我的后台，查看报价

发布成功！您可以继续发布采购。也可以进入我的后台，查看报价

我的联系方式