参数资料
型号: DS2152L
厂商: DALLAS SEMICONDUCTOR
元件分类: Digital Transmission Controller
英文描述: DATACOM, FRAMER, PQFP100
封装: LQFP-100
文件页数: 2/14页
文件大小: 1398K
代理商: DS2152L
10
Maxim Integrated
Adjustable Overvoltage and Overcurrent
Protectors with High Accuracy
MAX14571/MAX14572/MAX14573
Detailed Description
The MAX14571/MAX14572/MAX14573 are adjust-
able overvoltage- and overcurrent-protection devices
designed to protect systems against positive and nega-
tive input voltage faults up to Q40V, and feature low
100mI (typ) on-resistance FETs. If the input voltage
exceeds the OVLO threshold or falls below the UVLO,
the internal FETs are turned off to prevent damage to the
protected components. If the OVLO or the UVLO pin is
set below the external OVLO or UVLO select thresholds
(VOVLOSEL and VUVLOSEL), the device automatically
selects the internal Q3% (typ) accurate trip thresholds.
The internal OVLO threshold is preset to 33V (typ), and
the internal UVLO threshold is preset to 19.2V (typ).
The ICs feature programmable current-limit protection
up to 4.2A. Once current reaches the threshold, the
MAX14571 turns off after 20.7ms (typ) blanking time and
stays off during the retry period. The MAX14572 latches
off after the blanking time, and the MAX14573 limits the
current continuously.
Programmable Current Limit/Threshold
A resistor from SETI to GND sets the current limit/thresh-
old for the switch (see the Setting the Current Limit/
Threshold section). If the output current is limited at the
current threshold value for a time equal to or longer than
tBLANK, the output FLAG asserts and the MAX14571
enters the autoretry mode, the MAX14572 latches off
the switch, and the MAX14573 enters the continuous
current-limit mode.
Autoretry (MAX14571)
When the current threshold is reached, the tBLANK timer
begins counting. The FLAG asserts if the overcurrent
condition is present for tBLANK. The timer resets if the
overcurrent condition disappears before tBLANK has
elapsed. A retry time delay, tRETRY, is started immediately
after tBLANK has elapsed and during tRETRY time, the
FETs are off. At the end of tRETRY, the FETs are turned
on again. If the fault still exists, the cycle is repeated and
the FLAG stays low. When the fault is removed, the FETs
stay on. If the die temperature exceeds +150NC (typ)
due to self-heating, the MAX14571 enables thermal shut-
down until the die temperature drops by approximately
30NC (Figure 1).
The autoretry feature reduces the system power in case
of overcurrent or short-circuit conditions. During tBLANK
time, when the switch is on, the supply current is held
at the current limit. During tRETRY time, when the switch
is off, there is no current through the switch. Thus, the
output current is much less than the programmed cur-
rent limit. Calculate the average output current using the
following equation:
BLANK
LOAD
LIM
BLANK
RETRY
t
II
tt
=
+
With a 20.7ms (typ) tBLANK and 600ms (typ) tRETRY, the
duty cycle is 3.3%, resulting in a 96.7% power savings.
Latch-Off (MAX14572)
When the current threshold is reached, the tBLANK timer
begins counting. The FLAG asserts if the overcurrent
condition is present for tBLANK. The timer resets when
the overcurrent condition disappears before tBLANK
has elapsed. The switch turns off and stays off if the
overcurrent condition continues beyond the blanking
time. To reset the switch, either toggle the control logic
EN or HVEN or cycle the input voltage. If the die tem-
perature exceeds +150NC (typ) due to self-heating, the
MAX14572 latches off (Figure 2.)
Continuous Current Limit (MAX14573)
When the current threshold is reached, the MAX14573
limits the output current to the programmed current limit.
The FLAG asserts if the overcurrent condition is present
for tBLANK and deasserts when the overload condition is
removed. If the die temperature exceeds +150NC (typ) due
to self-heating, the MAX14573 enables thermal shutdown
until the die temperature drops by approximately 30NC
(Figure 3).
Reverse-Current Enable (RIEN)
This feature disables the reverse-current protection
and enables reverse-current flow from OUT to IN. The
reverse-current enable feature is useful in applications
with inductive loads.
Fault Flag Output
FLAG is an open-drain fault indicator output and requires
an external pullup resistor to a DC supply. FLAG goes
low when any of the following conditions occur:
Theblankingtimehaselapsed.
Thereverse-currentprotectionhastripped.
Thedietemperatureexceeds+150NC.
SETIisconnectedtoground.
OVLOthresholdisreached.
相关PDF资料
PDF描述
DS2153Q DATACOM, FRAMER, PQCC44
DS2154L DATACOM, FRAMER, PQFP100
DS21554L DATACOM, PCM TRANSCEIVER, PQFP100
DS21554LN DATACOM, PCM TRANSCEIVER, PQFP100
DS2155G DATACOM, FRAMER, PBGA100
相关代理商/技术参数
参数描述
DS2152L+ 功能描述:网络控制器与处理器 IC Enhanced T1 Transceiver RoHS:否 制造商:Micrel 产品:Controller Area Network (CAN) 收发器数量: 数据速率: 电源电流(最大值):595 mA 最大工作温度:+ 85 C 安装风格:SMD/SMT 封装 / 箱体:PBGA-400 封装:Tray
DS2152L-ES 制造商:DALL 功能描述:
DS2152LN 功能描述:网络控制器与处理器 IC RoHS:否 制造商:Micrel 产品:Controller Area Network (CAN) 收发器数量: 数据速率: 电源电流(最大值):595 mA 最大工作温度:+ 85 C 安装风格:SMD/SMT 封装 / 箱体:PBGA-400 封装:Tray
DS2152LN+ 功能描述:网络控制器与处理器 IC RoHS:否 制造商:Micrel 产品:Controller Area Network (CAN) 收发器数量: 数据速率: 电源电流(最大值):595 mA 最大工作温度:+ 85 C 安装风格:SMD/SMT 封装 / 箱体:PBGA-400 封装:Tray
DS2153DK 功能描述:KIT DESIGN TXRX E1 DS2153 RoHS:否 类别:编程器,开发系统 >> 过时/停产零件编号 系列:- 标准包装:1 系列:- 传感器类型:CMOS 成像,彩色(RGB) 传感范围:WVGA 接口:I²C 灵敏度:60 fps 电源电压:5.7 V ~ 6.3 V 嵌入式:否 已供物品:成像器板 已用 IC / 零件:KAC-00401 相关产品:4H2099-ND - SENSOR IMAGE WVGA COLOR 48-PQFP4H2094-ND - SENSOR IMAGE WVGA MONO 48-PQFP