- 您現(xiàn)在的位置：買賣IC網(wǎng) > PDF目錄383164 > ISL6740 (Intersil Corporation) Flexible Double Ended Voltage and Current Mode PWM Controllers PDF資料下載
參數(shù)資料
| 型號(hào)： | ISL6740 |
| 廠商： | Intersil Corporation |
| 英文描述： | Flexible Double Ended Voltage and Current Mode PWM Controllers |
| 中文描述： | 靈活的雙端電壓和電流模式PWM控制器 |
| 文件頁數(shù)： | 14/29頁 |
| 文件大?。?/td> | 639K |
| 代理商： | ISL6740 |
第1頁第2頁第3頁第4頁第5頁第6頁第7頁第8頁第9頁第10頁第11頁第12頁第13頁當(dāng)前第14頁第15頁第16頁第17頁第18頁第19頁第20頁第21頁第22頁第23頁第24頁第25頁第26頁第27頁第28頁第29頁
14
Fault Conditions
A fault condition occurs if V
REF
falls below 4.65V, the UV
input falls below 1.00V, the thermal protection is triggered, or
if OTS faults. When a fault is detected, OUTA and OUTB
outputs are disabled, the Fault signal is asserted, and the
soft start capacitor is quickly discharged. When the fault
condition clears and the soft start voltage is below the reset
threshold, a soft start cycle begins. The Fault signal is high
impedance during the soft start cycle.
An over current condition that results in shutdown (ISL6740),
or a short circuit shutdown also cause assertion of the Fault
signal. The difference between a current fault and the faults
described earlier is that the soft start capacitor is not quickly
discharged. The initiation of a new soft start cycle is delayed
while the soft start capacitor is discharged at a 15
μ
A rate.
This keeps the average output current to a minimum.
Thermal Protection
Two methods of over temperature protection are provided.
The first method is an on board temperature sensor that
protects the device should the junction temperature exceed
145
°
C. There is approximately 15
°
C of hysteresis.
The second method uses an internal comparator with a 2.5V
reference (V
REF
/2). The non-inverting input to the
comparator is accessible through the OTS pin. A thermistor
or thermal sensor located at or near the area of interest may
be connected to this input. There is a nominal 25
μ
A switched
current source used to create hysteresis. The current source
is active only during an OT fault; otherwise, it is inactive and
does not affect the node voltage. The magnitude of the
hysteresis is a function of the external resistor divider
impedance. Either a positive temperature coefficient (PTC)
or a negative temperature coefficient (NTC) thermistor may
be used. If a NTC is desired, position R1 may be substituted.
If a PTC is desired, then position R2 may be substituted. The
threshold with increasing temperature is set by making the
fixed resistance equal in value to the thermistor resistance at
the desired trip temperature.
V
TH
↑
= 2.5V and R1 = R2 (HOT)
To determine the value of the hysteresis resistor, R3, select
the value of thermistor resistance that corresponds to the
desired reset temperature.
If the hysteresis resistor, R3, is not desired, the value of the
thermistor resistance at the reset temperature can be
determined from:
The OTS comparator may also be used to monitor signals
other than suggested above. It may also be used to monitor
any voltage signal for which an excess requires a response
as described above. Input or output voltage monitoring are
examples of this.
Ground Plane Requirements
Careful layout is essential for satisfactory operation of the
device. A good ground plane must be employed. V
DD
should
be bypassed directly to GND with good high frequency
capacitance.
Typical Application
The Typical Application Schematic features the ISL6740 in
an unregulated half-bridge DC-DC converter configuration,
often referred to as a DC Transformer or Bus Regulator. The
ISL6740EVAL1 demonstration unit implements this design
and is available for evaluation.
The input voltage range is 48 ±10%V DC. The output is a
nominal 12V when the input voltage is at 48V. Since this is
an unregulated topology, the output voltage will vary
proportionately with input voltage. The load regulation is a
function of resistance between the source and the converter
output. The output is rated at 8A.
FIGURE 6. OTS HYSTERESIS
V
REF
R1
R2
R3
V
REF/2
25
μ
A
ON
+
-
V
REF
R3
5
--------------------------–
+
)
R1
R2
–
R1
R2
=
(EQ. 11)
R1
2.5
10
R2
–
----------------------------------------
=
NTC
(
)
(EQ. 12)
R2
2.5
10
R1
+
----------------------------------------
=
PTC
(
)
(EQ. 13)
ISL6740, ISL6741
相關(guān)PDF資料 |
PDF描述 |
|---|---|
| ISL6740IB | Flexible Double Ended Voltage and Current Mode PWM Controllers |
| ISL6740IV | Octal Buffers/Drivers With 3-State Outputs 20-SSOP -40 to 85 |
| ISL6741 | Flexible Double Ended Voltage and Current Mode PWM Controllers(靈活的雙端電壓和電流模式PWM控制器) |
| ISL6845IB | Improved Industry Standard Single Ended Current Mode PWM Controller |
| ISL6845 | Improved Industry Standard Single Ended Current Mode PWM Controller |
相關(guān)代理商/技術(shù)參數(shù) |
參數(shù)描述 |
|---|---|
| ISL6740AIVZA | 功能描述:IC REG CTRLR PWM VM 16-TSSOP RoHS:是 類別:集成電路 (IC) >> PMIC - 穩(wěn)壓器 - DC DC 切換控制器 系列:- 產(chǎn)品培訓(xùn)模塊:Lead (SnPb) Finish for COTS Obsolescence Mitigation Program 標(biāo)準(zhǔn)包裝:2,500 系列:- PWM 型:電流模式 輸出數(shù):1 頻率 - 最大:275kHz 占空比:50% 電源電壓:18 V ~ 110 V 降壓:無 升壓:無 回掃:無 反相:無 倍增器:無 除法器:無 Cuk:無 隔離:是 工作溫度:-40°C ~ 85°C 封裝/外殼:8-SOIC（0.154"，3.90mm 寬） 包裝:帶卷 (TR) |
| ISL6740AIVZA-T | 功能描述:IC REG CTRLR PWM VM 16-TSSOP RoHS:是 類別:集成電路 (IC) >> PMIC - 穩(wěn)壓器 - DC DC 切換控制器 系列:- 產(chǎn)品培訓(xùn)模塊:Lead (SnPb) Finish for COTS Obsolescence Mitigation Program 標(biāo)準(zhǔn)包裝:2,500 系列:- PWM 型:電流模式 輸出數(shù):1 頻率 - 最大:275kHz 占空比:50% 電源電壓:18 V ~ 110 V 降壓:無 升壓:無 回掃:無 反相:無 倍增器:無 除法器:無 Cuk:無 隔離:是 工作溫度:-40°C ~ 85°C 封裝/外殼:8-SOIC（0.154"，3.90mm 寬） 包裝:帶卷 (TR) |
| ISL6740EVAL1 | 功能描述:EVALUATION BOARD 1 ISL6740 RoHS:否 類別:編程器，開發(fā)系統(tǒng) >> 評(píng)估板 - DC/DC 與 AC/DC（離線）SMPS 系列:- 產(chǎn)品培訓(xùn)模塊:Obsolescence Mitigation Program 標(biāo)準(zhǔn)包裝:1 系列:True Shutdown™ 主要目的:DC/DC，步升 輸出及類型:1，非隔離 功率 - 輸出:- 輸出電壓:- 電流 - 輸出:1A 輸入電壓:2.5 V ~ 5.5 V 穩(wěn)壓器拓?fù)浣Y(jié)構(gòu):升壓 頻率 - 開關(guān):3MHz 板類型:完全填充 已供物品:板 已用 IC / 零件:MAX8969 |
| ISL6740EVAL2 | 功能描述:EVALUATION BOARD 2 ISL6740 RoHS:否 類別:編程器，開發(fā)系統(tǒng) >> 過時(shí)/停產(chǎn)零件編號(hào) 系列:- 標(biāo)準(zhǔn)包裝:1 系列:- 傳感器類型:CMOS 成像，彩色（RGB） 傳感范圍:WVGA 接口:I²C 靈敏度:60 fps 電源電壓: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 相關(guān)產(chǎn)品:4H2099-ND - SENSOR IMAGE WVGA COLOR 48-PQFP4H2094-ND - SENSOR IMAGE WVGA MONO 48-PQFP |
| ISL6740EVAL2Z | 功能描述:EVALUATION BOARD 2 ISL6740 RoHS:是 類別:編程器，開發(fā)系統(tǒng) >> 評(píng)估板 - DC/DC 與 AC/DC（離線）SMPS 系列:- 產(chǎn)品培訓(xùn)模塊:Obsolescence Mitigation Program 標(biāo)準(zhǔn)包裝:1 系列:True Shutdown™ 主要目的:DC/DC，步升 輸出及類型:1，非隔離 功率 - 輸出:- 輸出電壓:- 電流 - 輸出:1A 輸入電壓:2.5 V ~ 5.5 V 穩(wěn)壓器拓?fù)浣Y(jié)構(gòu):升壓 頻率 - 開關(guān):3MHz 板類型:完全填充 已供物品:板 已用 IC / 零件:MAX8969 |
發(fā)布緊急采購，3分鐘左右您將得到回復(fù)。