參數(shù)資料
型號: HV311
廠商: Supertex, Inc.
英文描述: Hotswap, Controllers with Circuit Breaker
中文描述: 熱插拔控制器與斷路器
文件頁數(shù): 5/21頁
文件大?。?/td> 664K
代理商: HV311
5
HV301/HV311
RAMP pin will be fixed, indicating that the circuit is in current limit
mode. Depending on the value of the load capacitor and the
programmed current limit, charging may continue for some time,
but may not exceed a nominal 100ms preset time limit. Once the
load capacitor has been charged, the output current will drop,
reducing the voltage on the SENSE pin, which in turn will
increase the RAMP pin current, thus causing the voltage on the
capacitor connected to the RAMP pin to continue rising, thereby
providing yet another programmed delay. If due to output over-
load conditions during startup, PWRGD does not achieve an
active state within 100ms or the circuit breaker is tripped, the
circuit is reset, pulling down the GATE to V
, discharging the
capacitor connected to the RAMP pin, changing PWRGD to an
inactive state. A timeout or circuit breaker fault will initiate an
auto-retry if enabled.
On the other hand, in feedback capacitor mode, a current source
of 10
μ
A from the RAMP pin limits the dv/dt of the feedback
capacitor which, in turn, programs Inrush according to
Inrush ~ 10
μ
AC
/C
. (See Programming Inrush and I
CB
for
accurate formula on page 6.)
When the ramp voltage is within 1.2V of the regulated internal
supply voltage, the controller will force the GATE terminal to a
nominal 10V, the PWRGD pin will change to an active state, the
circuit breaker supervisor is enabled and the circuit will transition
to a low power sleep mode.
When the voltage on the SENSE pin rises to 100mV, indicating
an over current condition, the circuit breaker will trip in less than
5
μ
s. This time may be extended by the addition of external
components.
At any time during the start up cycle or thereafter, crossing the
UV and OV limits (including hysteresis) will cause an immediate
reset of all internal circuitry. When the input supply voltage
returns to a value within the programmed UV and OV limits a new
start up sequence will be initiated.
Functional Description, cont’d.
Design Information
Setting UnderVoltage and OverVoltage Shut Down
The UV and OV pins are connected to comparators with nominal
1.21V thresholds and 100mV of hysteresis (1.21V
±
50mV).
They are used to detect under voltage and over voltage condi-
tions at the input to the circuit. Whenever the OV pin rises above
its high threshold (1.26V) or the UV pin falls below its low
threshold (1.16V) the GATE voltage is immediately pulled low,
the PWRGD pin changes to its inactive state and the external
capacitor connected to the RAMP pin is discharged.
Calculations can be based on either the desired input voltage
operating limits or the input voltage shutdown limits. In the
following equations the shutdown limits are assumed.
The undervoltage and overvoltage shut down thresholds can be
programmed by means of the three resistor divider formed by
R1, R2 and R3. Since the input currents on the UV and OV pins
are negligible the resistor values may be calculated as follows:
UV
V
V
R
+
R
+
R
R
R
OV
V
V
R
R
R
R
OFF
UVL
EEUV off
OFF
OVH
EEOV off
=
=
=
×
+
=
=
=
×
+
+
1 16
2
3
1
2
3
1 26
3
2
1
3
(
)
(
)
Where |
V
| and |
V
| relative to V
EE
are Under & Over
Voltage Shut Down Threshold points.
If we select a divider current of 100
μ
A at a nominal operating
input voltage of 50 Volts then
R
R
R
1
2
3
50
100
500
+
+
=
μ
=
V
A
k
From the second equation for an OV shut down threshold of 65V
the value of R3 may be calculated.
OV
R
R
OFF
=
=
×
=
×
=
1 26
65
500
3
3
1 26
.
500
65
9 69
k
k
k
The closest 1% value is 9.76k
.
From the first equation for a UV shut down threshold of 35V the
value of R2 can be calculated.
UV
R
R
R
OFF
=
=
×
+
(
)
=
×
=
1 16
.
35
2
k
3
500
2
1 16
.
500
35
9 76
.
6 81
.
k
k
k
The closest 1% value is 6.81k
.
Then
R
R
R
1
500
2
3
483
=
=
k
k
The closest 1% value is 487k
.
相關(guān)PDF資料
PDF描述
HV311LG Hotswap, Controllers with Circuit Breaker
HV302 Sequencing Hotswap Controllers
HV302DB1 Hotswap Controller
HV302NG Sequencing Hotswap Controllers
HV312 Sequencing Hotswap Controllers
相關(guān)代理商/技術(shù)參數(shù)
參數(shù)描述
HV311DB2 功能描述:電源管理IC開發(fā)工具 HV311 Demo Brd RoHS:否 制造商:Maxim Integrated 產(chǎn)品:Evaluation Kits 類型:Battery Management 工具用于評估:MAX17710GB 輸入電壓: 輸出電壓:1.8 V
HV311LG 功能描述:熱插拔功率分布 Active Low RoHS:否 制造商:Texas Instruments 產(chǎn)品:Controllers & Switches 電流限制: 電源電壓-最大:7 V 電源電壓-最小:- 0.3 V 工作溫度范圍: 功率耗散: 安裝風格:SMD/SMT 封裝 / 箱體:MSOP-8 封裝:Tube
HV311LG-G 功能描述:熱插拔功率分布 Active Low RoHS:否 制造商:Texas Instruments 產(chǎn)品:Controllers & Switches 電流限制: 電源電壓-最大:7 V 電源電壓-最小:- 0.3 V 工作溫度范圍: 功率耗散: 安裝風格:SMD/SMT 封裝 / 箱體:MSOP-8 封裝:Tube
HV311LG-M908 功能描述:熱插拔功率分布 -10 to -90V Activ Lw RoHS:否 制造商:Texas Instruments 產(chǎn)品:Controllers & Switches 電流限制: 電源電壓-最大:7 V 電源電壓-最小:- 0.3 V 工作溫度范圍: 功率耗散: 安裝風格:SMD/SMT 封裝 / 箱體:MSOP-8 封裝:Tube
HV311LG-M908-G 功能描述:熱插拔功率分布 -10 to -90V Activ Lw RoHS:否 制造商:Texas Instruments 產(chǎn)品:Controllers & Switches 電流限制: 電源電壓-最大:7 V 電源電壓-最小:- 0.3 V 工作溫度范圍: 功率耗散: 安裝風格:SMD/SMT 封裝 / 箱體:MSOP-8 封裝:Tube