- 您现在的位置：买卖IC网 > PDF目录15084 > ISL6520CB-T (Intersil)IC REG CTRLR BUCK PWM VM 8-SOIC PDF资料下载
参数资料
| 型号： | ISL6520CB-T |
| 厂商： | Intersil |
| 文件页数： | 4/11页 |
| 文件大小： | 0K |
| 描述： | IC REG CTRLR BUCK PWM VM 8-SOIC |
| 标准包装： | 2,500 |
| PWM 型： | 电压模式 |
| 输出数： | 1 |
| 频率 - 最大： | 340kHz |
| 占空比： | 100% |
| 电源电压： | 4.5 V ~ 5.5 V |
| 降压： | 是 |
| 升压： | 无 |
| 回扫： | 无 |
| 反相： | 无 |
| 倍增器： | 无 |
| 除法器： | 无 |
| Cuk： | 无 |
| 隔离： | 无 |
| 工作温度： | 0°C ~ 70°C |
| 封装/外壳： | 8-SOIC（0.154"，3.90mm 宽） |
| 包装： | 带卷 (TR) |
| 其它名称： | ISL6520CB-TR |
ISL6520
Functional Pin Description
VCC
This is the main bias supply for the ISL6520, as well as the
lower MOSFET’s gate. Connect a well-decoupled 5V supply
to this pin.
FB
This pin is the inverting input of the internal error amplifier. Use
this pin, in combination with the COMP/OCSET pin, to
compensate the voltage-control feedback loop of the converter.
GND
This pin represents the signal and power ground for the IC.
Tie this pin to the ground island/plane through the lowest
impedance connection available.
PHASE
Connect this pin to the upper MOSFET source. This pin is
used to monitor the voltage drop across the upper MOSFET
for over-current protection. This pin is also monitored by the
continuously adaptive shoot-through protection circuitry to
determine when the upper MOSFET has turned off.
UGATE
Connect this pin to the upper MOSFET’s gate. This pin
provides the PWM-controlled gate drive for the upper
MOSFET. This pin is also monitored by the adaptive shoot-
through protection circuitry to determine when the upper
MOSFET has turned off. Do not insert any circuitry between
this pin and the gate of the upper MOSFET, as it may
interfere with the internal adaptive shoot-through protection
circuitry and render it ineffective.
BOOT
This pin provides ground referenced bias voltage to the
upper MOSFET driver. A bootstrap circuit is used to create a
voltage suitable to drive a logic-level N-channel MOSFET.
COMP/OCSET
This is a multiplexed pin. During a short period of time following
power-on reset (POR), this pin is used to determine the over-
current threshold of the converter. Connect a resistor (R OCSET )
from this pin to the drain of the upper MOSFET (V CC ).
R OCSET , an internal 20 μ A current source (I OCSET ), and the
upper MOSFET on-resistance (r DS(ON) ) set the converter over-
current (OC) trip point according to the following equation:
An over-current trip cycles the soft-start function.
During soft-start, and all the time during normal converter
operation, this pin represents the output of the error amplifier.
Use this pin, in combination with the FB pin, to compensate the
voltage-control feedback loop of the converter.
Pulling OCSET to a level below 0.8V will disable the
controller. Disabling the ISL6520 causes the oscillator to
stop, the LGATE and UGATE outputs to be held low, and the
softstart circuitry to re-arm.
LGATE
Connect this pin to the lower MOSFET’s gate. This pin provides
the PWM-controlled gate drive for the lower MOSFET. This pin
is also monitored by the adaptive shoot-through protection
circuitry to determine when the lower MOSFET has turned off.
Do not insert any circuitry between this pin and the gate of the
lower MOSFET, as it may interfere with the internal adaptive
shoot-through protection circuitry and render it ineffective.
Functional Description
Initialization
The ISL6520 automatically initializes upon receipt of power.
The Power-On Reset (POR) function continually monitors the
bias voltage at the VCC pin. The POR function initiates the
Over-Current Protection (OCP) sampling and hold operation
after the supply voltage exceeds its POR threshold. Upon
completion of the OCP sampling and hold operation, the POR
function initiates the Soft Start operation.
Over Current Protection
The over-current function protects the converter from a
shorted output by using the upper MOSFET’s on-resistance,
r DS(ON) , to monitor the current. This method enhances the
converter’s efficiency and reduces cost by eliminating a
current sensing resistor.
The over-current function cycles the soft-start function in a
hiccup mode to provide fault protection. A resistor
(R OCSET ) programs the over-current trip level (see See
Immediately following POR, the ISL6520 initiates the Over-
Current Protection sampling and hold operation. First, the
internal error amplifier is disabled. This allows an internal
20 μ A current sink to develop a voltage across R OCSET . The
ISL6520 then samples this voltage at the COMP pin. This
r DS ( ON )
I OCSET xR OCSET
I PEAK = -------------------------------------------------
(EQ. 1)
sampled voltage, which is referenced to the VCC pin, is held
internally as the Over-Current Set Point.
Internal circuitry of the ISL6520 will not recognize a voltage
drop across R OCSET larger than 0.5V. Any voltage drop
across R OCSET that is greater than 0.5V will set the
overcurrent trip point to:
When the voltage across the upper MOSFET, which is also
referenced to the VCC pin, exceeds the Over-Current Set
Point, the over-current function initiates a soft-start sequence.
Figure 1 shows the inductor current after a fault is introduced
I PEAK = ----------------------
0.5V
r DS ( ON )
4
(EQ. 2)
while running at 15A. The continuous fault causes the
ISL6520 to go into a hiccup mode with a typical period of
25ms. The inductor current increases to 18A during the Soft
FN9009.6
April 3, 2007
相关PDF资料 |
PDF描述 |
|---|---|
| X4045S8IZ | IC CPU SUPERV 4K EEPROM 8-SOIC |
| VI-20H-EY-B1 | CONVERTER MOD DC/DC 52V 50W |
| ISL6520ACB-T | IC REG CTRLR BUCK PWM VM 8-SOIC |
| X4043S8IZ-2.7A | IC CPU SUPERV 4K EEPROM 8-SOIC |
| VI-25X-EW-F3 | CONVERTER MOD DC/DC 5.2V 100W |
相关代理商/技术参数 |
参数描述 |
|---|---|
| ISL6520CBZ | 功能描述:IC REG CTRLR BUCK PWM VM 8-SOIC RoHS:是 类别:集成电路 (IC) >> PMIC - 稳压器 - DC DC 切换控制器 系列:- 产品培训模块:Lead (SnPb) Finish for COTS Obsolescence Mitigation Program 标准包装:2,500 系列:- PWM 型:电流模式 输出数:1 频率 - 最大:275kHz 占空比:50% 电源电压:18 V ~ 110 V 降压:无 升压:无 回扫:无 反相:无 倍增器:无 除法器:无 Cuk:无 隔离:是 工作温度:-40°C ~ 85°C 封装/外壳:8-SOIC（0.154"，3.90mm 宽） 包装:带卷 (TR) |
| ISL6520CBZ-T | 功能描述:IC REG CTRLR BUCK PWM VM 8-SOIC RoHS:是 类别:集成电路 (IC) >> PMIC - 稳压器 - DC DC 切换控制器 系列:- 产品培训模块:Lead (SnPb) Finish for COTS Obsolescence Mitigation Program 标准包装:2,500 系列:- PWM 型:电流模式 输出数:1 频率 - 最大:275kHz 占空比:50% 电源电压:18 V ~ 110 V 降压:无 升压:无 回扫:无 反相:无 倍增器:无 除法器:无 Cuk:无 隔离:是 工作温度:-40°C ~ 85°C 封装/外壳:8-SOIC（0.154"，3.90mm 宽） 包装:带卷 (TR) |
| ISL6520CR | 功能描述:IC REG CTRLR BUCK PWM VM 16-QFN RoHS:否 类别:集成电路 (IC) >> PMIC - 稳压器 - DC DC 切换控制器 系列:- 标准包装:4,000 系列:- PWM 型:电压模式 输出数:1 频率 - 最大:1.5MHz 占空比:66.7% 电源电压:4.75 V ~ 5.25 V 降压:是 升压:无 回扫:无 反相:无 倍增器:无 除法器:无 Cuk:无 隔离:无 工作温度:-40°C ~ 85°C 封装/外壳:40-VFQFN 裸露焊盘 包装:带卷 (TR) |
| ISL6520CR-T | 功能描述:IC REG CTRLR BUCK PWM VM 16-QFN RoHS:否 类别:集成电路 (IC) >> PMIC - 稳压器 - DC DC 切换控制器 系列:- 标准包装:4,000 系列:- PWM 型:电压模式 输出数:1 频率 - 最大:1.5MHz 占空比:66.7% 电源电压:4.75 V ~ 5.25 V 降压:是 升压:无 回扫:无 反相:无 倍增器:无 除法器:无 Cuk:无 隔离:无 工作温度:-40°C ~ 85°C 封装/外壳:40-VFQFN 裸露焊盘 包装:带卷 (TR) |
| ISL6520CRZ | 功能描述:IC REG CTRLR BUCK PWM VM 16-QFN RoHS:是 类别:集成电路 (IC) >> PMIC - 稳压器 - DC DC 切换控制器 系列:- 产品培训模块:Lead (SnPb) Finish for COTS Obsolescence Mitigation Program 标准包装:2,500 系列:- PWM 型:电流模式 输出数:1 频率 - 最大:275kHz 占空比:50% 电源电压:18 V ~ 110 V 降压:无 升压:无 回扫:无 反相:无 倍增器:无 除法器:无 Cuk:无 隔离:是 工作温度:-40°C ~ 85°C 封装/外壳:8-SOIC（0.154"，3.90mm 宽） 包装:带卷 (TR) |
发布紧急采购，3分钟左右您将得到回复。