參數(shù)資料
型號: TD230IDT
廠商: STMICROELECTRONICS
元件分類: 電源管理
英文描述: 1-CHANNEL POWER SUPPLY SUPPORT CKT, PDSO16
封裝: MICRO, PLASTIC, SO-16
文件頁數(shù): 12/15頁
文件大?。?/td> 497K
代理商: TD230IDT
6/15
Do
no
t u
se
for
new
design
INTRODUCTION
Over current and short circuit protection is a con-
stant concern for today’s engineers. More and
more applications in different segments (Telecom,
Automotive, Industrial, Computer...) require al-
ways improved reliability after delivery : mainte-
nance costs are an ever more worrying source of
expenses and customers’ dissatisfaction.
Alternatives for short circuit or over current protec-
tions are the fuses and the PTC (Positive Temper-
ature Coefficient) resistors. The first are a cheap
but destructive solution ; the second are tied to a
time constant due to self heating which is often in-
compatible with the host equipment’s require-
ments.
In both cases, a coil can be added for an efficient
limitation of current surges, to the detriment of
weight and volume.
None of these solutions is fully satisfactory for a
reliable, immediate and non destructible short cir-
cuit and over current protection.
1. ELECTRONIC CIRCUIT BREAKER
The electronic circuit breaker TD230 is the conve-
nient solution for any industrial who wants at the
same time :
u immediate, efficient and resettable protec-
tion for his equipment
u versatility regarding different applications
u easy and quick design-in
u low component count
u low cost
The electronic circuit breaker TD230 is to be used
with a minimal amount of external and low cost
components to drive one or two N-channel MOS-
FETs (in respectively single or dual supply appli-
cations) used as power switches between the DC
power supplies and the equipments to be
protected.
The TD230 immediately reacts (3
s max. without
load) whenever an over current is detected by
switching off the corresponding MOSFET. Several
automatic restart attempts are made unless the
fault persists over an externally adjustable amount
of time after which the power MOSFET is defini-
tively switched off, waiting for a reset.
If the fault is detected on the positive supply, the
definitive shutdown will also disconnect the nega-
tive power supply and set a warning low level on
the Shutdown pin. If the fault is detected on the
negative supply, the definitive shutdown will dis-
connect only the negative power supply, and let
the positive part of the circuit undisturbed.
The whole system can be reset in three ways :
u by switching off the power supplies
u by unplugging and re-plugging the card
(live insertion)
u by setting the INHIBIT pin active during a
short time (allowing remote reset)
2. HOW TO USE THE TD230 ?
The typical configuration of the TD230 - Electronic
Circuit Breaker - in a dual supply topology is
shown in figure 1.
In this configuration, both NMOS 1/2 are used as
power switches which connect the equipments to
the power supplies, thus ensuring low voltage
drop through the ON-resistances (Rdson) of
NMOS
1/2.
2.1. Current Limitation
When an over current condition (I
OC) is detected
through the low ohmic shunt resistors RS 1/2 as giv-
en under equation (i) :
u V
RS 1/2 = IOC x RS > 63mV typ. (i)
the gate of the corresponding MOSFET 1/2 is dis-
charged immediately, thus disconnecting the
board/equipment from the power supply.
Note that the over current condition is given by the
constant product I
OC x RS = 63mV, which means
that the IOC limit is directly given by the choice of
the shunt resistors R
S1/2 values.
The TD230 automatically makes restart attempts
by slowly recharging the gate of the MOSFET 1/2
with a 15
A typ. current source ensuring thus slow
ramp with the typical time constant before recon-
duction shown in equation (ii) :
u t
ON = CISS x VTH / 15A (ii)
where CISS is the input capacitance of the power
MOSFET
1/2 and VTH, the threshold voltage of the
MOSFET (typically 5V).
This reconduction time can be extended with an
external soft start capacitor C
SS1/2 as shown in
APPLICATION NOTE
ELECTRONIC CIRCUIT BREAKER
by R. LIOU
相關(guān)PDF資料
PDF描述
TD62650FG 1-CHANNEL POWER SUPPLY SUPPORT CKT, PDSO30
TD62652FG 1-CHANNEL POWER SUPPLY SUPPORT CKT, PDSO30
TDA16832G 2.7 A SWITCHING REGULATOR, 110 kHz SWITCHING FREQ-MAX, PDSO14
TDA16833G 4.8 A SWITCHING REGULATOR, 110 kHz SWITCHING FREQ-MAX, PDSO14
TDA16831 1.4 A SWITCHING REGULATOR, 110 kHz SWITCHING FREQ-MAX, PDIP8
相關(guān)代理商/技術(shù)參數(shù)
參數(shù)描述
TD230IN 功能描述:電源開關(guān) IC - 配電 Circuit Breaker RoHS:否 制造商:Exar 輸出端數(shù)量:1 開啟電阻(最大值):85 mOhms 開啟時間(最大值):400 us 關(guān)閉時間(最大值):20 us 工作電源電壓:3.2 V to 6.5 V 電源電流(最大值): 最大工作溫度:+ 85 C 安裝風(fēng)格:SMD/SMT 封裝 / 箱體:SOT-23-5
TD230N 制造商:STMICROELECTRONICS 制造商全稱:STMicroelectronics 功能描述:ELECTRONIC CIRCUIT BREAKER
TD231 制造商:未知廠家 制造商全稱:未知廠家 功能描述:Technical Specifications for 5 kA, Normal-Duty Distribution 4.5 kV and 5 kV VariSTAR?? MOV Disks
TD231-1000P 制造商:TE Connectivity 功能描述:TIME DELAY RELAY - Trays
TD231-1000S 制造商:TE Connectivity 功能描述:TIME DELAY RELAY - Trays