?/DIV>
N pin high then low again or bringing the bias
input, V
CC
below its UVLO threshold for more than 100約
will initiate the debounce timing cycle and reset all fault
latches before power-up. Bringing AUXIN or 12V
IN
below its
undervoltage threshold will not reset the fault latches. For
the auto-retry version (LTC4223-2), the latched fault will
be cleared automatically after a cool-off timing cycle.
Auto-Retry after a Fault (LTC4223-2)
At time point 1 in Figure 8, if a fault latched-off the 3.3V
auxiliary supply after power-up, a cool-off cycle begins.
The TIMER capacitor charges up to 1.235V with a 10糀
current and then discharges with a 2糀 current to 0.2V at
time point 3. This is followed by a debounce timing cycle
whereby the fault latch is cleared, and
?/DIV>
F
?/DIV>
A
?/DIV>
U
?/DIV>
L
?/DIV>
T pulls high
when TIMER reaches its threshold at time point 4. At the
end of debounce cycle, the internal switch is allowed to
turn on. If the output short persists, the auxiliary supply
powers up into a short with active current limiting. At time
point 7, the fault lter delay begins with TIMER ramping
up with a 10糀 current. If the TIMER times out at time
point 8,
?/DIV>
F
?/DIV>
A
?/DIV>
U
?/DIV>
L
?/DIV>
T will be pulled low and a new cool-off cycle
begins with TIMER ramping down with a 2糀 current.
The whole process repeats itself until the output-short
is removed.
In Figure 9, a fault latches off the 12V supply at time point
1; a cool-off cycle begins by discharging the TIMER ca-
pacitor with 2糀 current from 1.235V to 0.2V threshold.
At time point 2 a new debounce timing cycle is initiated
where the fault latch is cleared, and
?/DIV>
F
?/DIV>
A
?/DIV>
U
?/DIV>
L
?/DIV>
T pulls high when
TIMER reaches its threshold at time point 3. At the end of
the debounce cycle, the 12V GATE is allowed to start up. If
the output short persists, the 12V supply powers up into a
short with active current limiting. At time point 6, the fault
lter delay begins with TIMER ramping up with a 200糀
current. The TIMER times out at time point 7,
?/DIV>
F
?/DIV>
A
?/DIV>
U
?/DIV>
L
?/DIV>
T pulls
low and a new cool-off cycle begins with TIMER ramping
down with a 2糀 current. The whole process repeats itself
until the output-short is removed.
The auto-retry duty cycle is given by:
DutyCycle
t
t
t
t
FILTER
COOL    DEBOUNCE    FILT
=
+
+
"
%
100
EER
For example, if TIMER capacitor, C
T
= 0.1糉, the auto-retry
duty cycle for auxiliary and 12V supply is 6.5% and 0.5%
respectively.
相关代理商/技术参数 |
参数描述 |
| LTC4223CDHD-2TRPBF |
制造商:LINER 制造商全称:Linear Technology 功能描述:Dual Supply Hot Swap Controller for Advanced Mezzanine Card |
| LTC4223CGN-1#PBF |
功能描述:IC CNTRLR HOT SWAP DUAL 16-SSOP RoHS:是 类别:集成电路 (IC) >> PMIC - 热交换 系列:- 标准包装:50 系列:- 类型:热交换控制器 应用:-48V 远程电力系统,AdvancedTCA ? 系统,高可用性 内部开关:无 电流限制:可调 电源电压:11.5 V ~ 14.5 V 工作温度:-40°C ~ 85°C 安装类型:表面贴装 封装/外壳:10-TFSOP,10-MSOP(0.118",3.00mm 宽) 供应商设备封装:10-MSOP 包装:管件 |
| LTC4223CGN-1#TRPBF |
功能描述:IC CNTRLR HOT SWAP DUAL 16-SSOP RoHS:是 类别:集成电路 (IC) >> PMIC - 热交换 系列:- 标准包装:50 系列:- 类型:热交换控制器 应用:-48V 远程电力系统,AdvancedTCA ? 系统,高可用性 内部开关:无 电流限制:可调 电源电压:11.5 V ~ 14.5 V 工作温度:-40°C ~ 85°C 安装类型:表面贴装 封装/外壳:10-TFSOP,10-MSOP(0.118",3.00mm 宽) 供应商设备封装:10-MSOP 包装:管件 |
| LTC4223CGN-1PBF |
制造商:LINER 制造商全称:Linear Technology 功能描述:Dual Supply Hot Swap Controller for Advanced Mezzanine Card |
| LTC4223CGN-1TRPBF |
制造商:LINER 制造商全称:Linear Technology 功能描述:Dual Supply Hot Swap Controller for Advanced Mezzanine Card |