- 您现在的位置：买卖IC网 > PDF目录15184 > ISL6439IBZ (Intersil)IC REG CTRLR BUCK PWM VM 14-SOIC PDF资料下载
参数资料
| 型号： | ISL6439IBZ |
| 厂商： | Intersil |
| 文件页数： | 8/15页 |
| 文件大小： | 0K |
| 描述： | IC REG CTRLR BUCK PWM VM 14-SOIC |
| 标准包装： | 500 |
| PWM 型： | 电压模式 |
| 输出数： | 1 |
| 频率 - 最大： | 340kHz |
| 占空比： | 100% |
| 电源电压： | 3.3 V ~ 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： | -40°C ~ 85°C |
| 封装/外壳： | 14-SOIC（0.154"，3.90mm 宽） |
| 包装： | 管件 |
ISL6439, ISL6439A
+3.3V
VCC
CPVOUT
BOOT
D1
VIN
V OUT (2.5V)
ISL6439
UGATE
PHASE
C4
Q1
L OUT
V OUT
0V
LGATE
Q2
+
C OUT
Internal Soft-Start Function
FB
COMP
C1
R1
C3
R3
Delay Interval
C2
R2
R4
T0
T1
T2
TIME
FIGURE 3. OVER CURRENT PROTECTION RESPONSE
3. Determine I PEAK for I PEAK > I OUT ( MAX ) + ---------- ,
FIGURE 2. OUTPUT VOLTAGE SELECTION
The overcurrent function cycles the soft-start function in a
hiccup mode to provide fault protection. A resistor (R OCSET )
programs the overcurrent trip level (see Typical Application
diagrams on pages 2 and 3). An internal 20 μ A (typical) current
sink develops a voltage across R OCSET that is referenced to
V IN . When the voltage across the upper MOSFET (also
referenced to V IN ) exceeds the voltage across R OCSET , the
overcurrent function initiates a soft-start sequence.
Figure 3 illustrates the protection feature responding to an
overcurrent event. At time t0, an overcurrent condition is
sensed across the upper MOSFET. As a result, the regulator
is quickly shutdown and the internal soft-start function begins
producing soft-start ramps. The delay interval seen by the
output is equivalent to three soft-start cycles. The fourth
internal soft-start cycle initiates a normal soft-start ramp of
the output, at time t1. The output is brought back into
regulation by time t2, as long as the overcurrent event has
cleared.
Had the cause of the over current still been present after the
delay interval, the over current condition would be sensed
and the regulator would be shut down again for another
delay interval of three soft-start cycles. The resulting hiccup
mode style of protection would continue to repeat
indefinitely.
The overcurrent function will trip at a peak inductor current
(I PEAK) determined by Equation 3:
r DS(ON) variations. To avoid overcurrent tripping in the
normal operating load range, find the R OCSET resistor from
the equation above with:
1. The maximum r DS(ON) at the highest junction
temperature.
2. The minimum I OCSET from the specification table.
( Δ I )
2
where Δ I is the output inductor ripple current.
For an equation for the ripple current see the section under
component guidelines titled ‘Output Inductor Selection’.
A small ceramic capacitor should be placed in parallel with
R OCSET to smooth the voltage across R OCSET in the
presence of switching noise on the input voltage.
Current Sinking
The ISL6439 incorporates a MOSFET shoot-through
protection method which allows a converter to sink current
as well as source current. Care should be exercised when
designing a converter with the ISL6439 when it is known that
the converter may sink current.
When the converter is sinking current, it is behaving as a
boost converter that is regulating its input voltage. This
means that the converter is boosting current into the input
rail of the regulator. If there is nowhere for this current to go,
such as to other distributed loads on the rail or through a
voltage limiting protection device, the capacitance on this rail
will absorb the current. This situation will allow the voltage
I PEAK = -----------------------------------------------------
I OCSET x R OCSET
r DS ( ON )
(EQ. 3)
level of the input rail to increase. If the voltage level of the rail
is boosted to a level that exceeds the maximum voltage
rating of any components attached to the input rail, then
where I OCSET is the internal OCSET current source (20 μ A
typical). The OC trip point varies mainly due to the MOSFET
8
those components may experience an irreversible failure or
experience stress that may shorten their lifespan. Ensuring
FN9057.5
November 5, 2008
相关PDF资料 |
PDF描述 |
|---|---|
| ISL8106CRZ-T | IC REG CTRLR BUCK PWM VM 16-QFN |
| B41041B8108M | 1000UF 63V 16X40 SINGLE END |
| VI-2T1-EW-F4 | CONVERTER MOD DC/DC 12V 100W |
| VI-2T1-EW-F2 | CONVERTER MOD DC/DC 12V 100W |
| VI-2T1-EW-F1 | CONVERTER MOD DC/DC 12V 100W |
相关代理商/技术参数 |
参数描述 |
|---|---|
| ISL6439IBZ-T | 功能描述:IC REG CTRLR BUCK PWM VM 14-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) |
| ISL6439IBZ-TS2705 | 制造商:Intersil Corporation 功能描述:CISCO, ISL6439IBZ-T W/CONTAINER LABELING - Tape and Reel |
| ISL6439IR | 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) |
| ISL6439IR-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) |
| ISL6439IRZ | 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。