參數(shù)資料
型號: ISL6741
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): 12/21頁
文件大?。?/td> 507K
代理商: ISL6741
12
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
= 2.5 V 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.
Circuit Element Descriptions
The converter design may be broken down into the following
functional blocks:
Input Filtering: L1,C1, R1
Half-Bridge Capacitors: C2, C3
Isolation Transformer: T1
Primary Snubber: C13, R10
Start Bias Regulator: CR3, R2, R7, C6, Q5, D1
Supply Bypass Components: R3, C15, C4, C5
Main MOSFET Power Switch: QH, QL
Current Sense Network: T2, CR1, CR2, R5, R6, R11, C10,
C14
Control Circuit: U3, RT1, R14, R19, R13, R15, R17, R18,
C16, C18, C17
Output Rectification and Filtering: QR1, QR2, QR3, QR4, L2,
C9, C8
Secondary Snubber: R8, R9, C11, C12
FET Driver: U1
ZVS Resonant Delay (Optional): L3, C7
Design Criteria
The following design requirements were selected:
Switching Frequency, Fsw: 235kHz
V
IN
: 48 ±10%V
V
OUT
: 12V (nominal) @ I
OUT
= 8A
P
OUT
: 100W
Efficiency: 95%
Ripple: 1%
Transformer Design
The design of a transformer for a half-bridge application is a
straight forward affair, although iterative. It is a process of
many compromises, and even experienced designers will
FIGURE 6. OTS HYSTERESIS
V
REF
R1
R2
R3
V
REF/2
25
μ
A
ON
+
-
V
REF
R3
5
--------------------------–
)
R1
R2
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
ISL72991 Radiation Hardened Negative Low Dropout Adjustable Voltage Regulator
ISL74422RH Radiation Hardened 9A. Non-Inverting Power MOSFET Drivers
ISL74422ARHVF Radiation Hardened 9A, Non-Inverting Power MOSFET Drivers
ISL74422BRHVF Radiation Hardened, 9A, Non-Inverting Power MOSFET Driver
ISL74422ARHQF Radiation Hardened 9A, Non-Inverting Power MOSFET Drivers
相關(guān)代理商/技術(shù)參數(shù)
參數(shù)描述
ISL6741IB 功能描述:電流型 PWM 控制器 CUR PWM MODE CNTRLR 16LD N RoHS:否 制造商:Texas Instruments 開關(guān)頻率:27 KHz 上升時間: 下降時間: 工作電源電壓:6 V to 15 V 工作電源電流:1.5 mA 輸出端數(shù)量:1 最大工作溫度:+ 105 C 安裝風(fēng)格:SMD/SMT 封裝 / 箱體:TSSOP-14
ISL6741IB-T 功能描述:IC REG CTRLR PWM CM 16-SOIC RoHS:否 類別:集成電路 (IC) >> PMIC - 穩(wěn)壓器 - DC DC 切換控制器 系列:- 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:500kHz 占空比:100% 電源電壓:8.2 V ~ 30 V 降壓:無 升壓:無 回掃:是 反相:無 倍增器:無 除法器:無 Cuk:無 隔離:是 工作溫度:0°C ~ 70°C 封裝/外殼:8-DIP(0.300",7.62mm) 包裝:管件 產(chǎn)品目錄頁面:1316 (CN2011-ZH PDF)
ISL6741IBZ 功能描述:IC REG CTRLR PWM CM 16-SOIC 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)
ISL6741IBZ-T 功能描述:IC REG CTRLR PWM CM 16-SOIC 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)
ISL6741IV 功能描述:IC REG CTRLR PWM CM 16-TSSOP RoHS:否 類別:集成電路 (IC) >> PMIC - 穩(wěn)壓器 - DC DC 切換控制器 系列:- 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:500kHz 占空比:100% 電源電壓:8.2 V ~ 30 V 降壓:無 升壓:無 回掃:是 反相:無 倍增器:無 除法器:無 Cuk:無 隔離:是 工作溫度:0°C ~ 70°C 封裝/外殼:8-DIP(0.300",7.62mm) 包裝:管件 產(chǎn)品目錄頁面:1316 (CN2011-ZH PDF)