参数资料
型号: ISL62392HRTZ-T
厂商: Intersil
文件页数: 15/21页
文件大小: 0K
描述: IC PWR SUPPLY CONTROLLER 28TQFN
标准包装: 6,000
应用: 电源控制器
电源电压: 5.5 V ~ 25 V
电流 - 电源: 150µA
工作温度: -10°C ~ 100°C
安装类型: 表面贴装
封装/外壳: 28-WFQFN 裸露焊盘
供应商设备封装: 28-TQFN-EP(4x4)
包装: 带卷 (TR)
ISL62391, ISL62392, ISL62391C, ISL62392C
over the entire load range. This will produce the best transient
response to all load conditions, but will have increased
light-load power loss. If FCCM is forced low, the ISL62391,
ISL62392, ISL62391C and ISL62392C will automatically
operate in Diode Emulation Mode (DEM) at light load to
optimize efficiency in the entire load range. The transition is
automatically achieved by detecting the load current and
turning off LGATE when the inductor current reaches 0A.
Positive-going inductor current flows from either the source
of the high-side MOSFET, or the drain of the low-side
MOSFET. Negative-going inductor current flows into the
drain of the low-side MOSFET. When the low-side MOSFET
conducts positive inductor current, the phase voltage will be
negative with respect to the GND and PGND pins.
circuits. To prevent this from occurring, the ISL62391,
ISL62392, ISL62391C and ISL62392C allow the user to float
the FCCM input. This will allow DEM at light loads, but will
prevent the switching frequency from going below ~28kHz to
prevent noise injection to the audio band. A timer is reset
each PWM pulse. If the timer exceeds 30μs, LGATE is
turned on, causing the ramp voltage to reduce until another
UGATE is commanded by the voltage loop.
Overcurrent Protection
The overcurrent protection (OCP) setpoint is programmed
with resistor, R OCSET , that is connected across the OCSET
and PHASE pins.
L
Conversely, when the low-side MOSFET conducts negative
inductor current, the phase voltage will be positive with
respect to the GND and PGND pins. The ISL62391,
ISL62392, ISL62391C and ISL62392C monitor the phase
PHASE1
ISL62391,
ISL62392
+
DCR
R OCSET
V DCR
C SEN
I L
_
V O
C O
voltage when the low-side MOSFET is conducting inductor
current to determine its direction.
10μA
OCSET1
+ V ROCSET
_
When the output load current is greater than or equal to ?
the inductor ripple current, the inductor current is always
positive, and the converter is always in CCM. The ISL62391,
ISL62392, ISL62391C and ISL62392C minimize the
conduction loss in this condition by forcing the low-side
MOSFET to operate as a synchronous rectifier.
When the output load current is less than ? the inductor
ripple current, negative inductor current occurs. Sinking
R O
ISEN1
FIGURE 26. OVERCURRENT-SET CIRCUIT
Figure 26 shows the overcurrent-set circuit for SMPS1. The
inductor consists of inductance L and the DC resistance
(DCR). The inductor DC current I L creates a voltage drop
across DCR, which is given by Equation 6:
negative inductor through the low-side MOSFET lowers
efficiency through unnecessary conduction losses. The
V DCR = I L ? DCR
(EQ. 6)
ISL62391, ISL62392, ISL62391C and ISL62392C
automatically enter DEM after the PHASE pin has detected
positive voltage and LGATE was allowed to go high for 8
consecutive PWM switching cycles. The ISL62391,
The ISL62391, ISL62392, ISL62391C and ISL62392C sink a
10μA current into the OCSET1 pin, creating a DC voltage
drop across the resistor R OCSET , which is given by
Equation 7:
ISL62392, ISL62391C and ISL62392C will turn off the low-
side MOSFET once the phase voltage turns positive,
V ROCSET = 10 μ A ? R OCSET
(EQ. 7)
indicating negative inductor current. The ISL62391,
ISL62392, ISL62391C and ISL62392C will return to CCM on
the following cycle after the PHASE pin detects negative
voltage, indicating that the body diode of the low-side
MOSFET is conducting positive inductor current.
Efficiency can be further improved with a reduction of
Resistor R O is connected between the ISEN1 pin and the
actual output voltage of the converter. During normal
operation, the ISEN1 pin is a high impedance path, therefore
there is no voltage drop across R O . The DC voltage
difference between the OCSET1 pin and the ISEN1 pin can
be established using Equation 8:
unnecessary switching losses by reducing the PWM
frequency. It is characteristic of the R 3 architecture for the
PWM frequency to decrease while in diode emulation. The
V OCSET1 – V ISEN1 = I L ? DCR – 10 μ A ? R OCSET
(EQ. 8)
extent of the frequency reduction is proportional to the
reduction of load current. Upon entering DEM, the PWM
frequency makes an initial step-reduction because of a 33%
step-increase of the window voltage V W .
Because the switching frequency in DEM is a function of
load current, very light load conditions can produce
The ISL62391, ISL62392, ISL62391C and ISL62392C
monitor the OCSET1 pin and the ISEN1 pin voltages. Once
the OCSET1 pin voltage is higher than the ISEN1 pin voltage
for more than 10μs, the ISL62391, ISL62392, ISL62391C and
ISL62392C declare an OCP fault. The value of R OCSET is
then written as Equation 9:
R OCSET = ---------------------------
frequencies well into the audio band. This can be
problematic if audible noise is coupled into audio amplifier
15
I OC ? DCR
10 μ A
(EQ. 9)
FN6666.7
August 22, 2013
相关PDF资料
PDF描述
GEA28DTMN CONN EDGECARD 56POS R/A .125 SLD
MAX6164AESA IC VREF SERIES PREC 4.096V 8SOIC
H3AAH-1036M IDC CABLE - HSC10H/AE10M/HSC10H
REC5-0512DRW/H4/C CONV DC/DC 5W 4.5-9VIN +/-12VOUT
MAX6163AESA IC VREF SERIES PREC 3V 8-SOIC
相关代理商/技术参数
参数描述
ISL62392IRTZ 功能描述:IC PWR SUPPLY CONTROLLER 28TQFN RoHS:是 类别:集成电路 (IC) >> PMIC - 电源控制器,监视器 系列:- 产品培训模块:Lead (SnPb) Finish for COTS Obsolescence Mitigation Program 标准包装:2,500 系列:- 应用:多相控制器 输入电压:- 电源电压:9 V ~ 14 V 电流 - 电源:- 工作温度:-40°C ~ 85°C 安装类型:表面贴装 封装/外壳:40-WFQFN 裸露焊盘 供应商设备封装:40-TQFN-EP(5x5) 包装:带卷 (TR)
ISL62392IRTZ-T 功能描述:IC PWR SUPPLY CONTROLLER 28TQFN RoHS:是 类别:集成电路 (IC) >> PMIC - 电源控制器,监视器 系列:- 产品培训模块:Lead (SnPb) Finish for COTS Obsolescence Mitigation Program 标准包装:2,500 系列:- 应用:多相控制器 输入电压:- 电源电压:9 V ~ 14 V 电流 - 电源:- 工作温度:-40°C ~ 85°C 安装类型:表面贴装 封装/外壳:40-WFQFN 裸露焊盘 供应商设备封装:40-TQFN-EP(5x5) 包装:带卷 (TR)
ISL62392LOEVAL1Z 功能描述:EVALUATION BOARD FOR ISL62392LO RoHS:是 类别:编程器,开发系统 >> 评估板 - DC/DC 与 AC/DC(离线)SMPS 系列:Robust Ripple Regulator™ (R³) 产品培训模块:Obsolescence Mitigation Program 标准包装:1 系列:True Shutdown™ 主要目的:DC/DC,步升 输出及类型:1,非隔离 功率 - 输出:- 输出电压:- 电流 - 输出:1A 输入电压:2.5 V ~ 5.5 V 稳压器拓扑结构:升压 频率 - 开关:3MHz 板类型:完全填充 已供物品:板 已用 IC / 零件:MAX8969
ISL6244 制造商:INTERSIL 制造商全称:Intersil Corporation 功能描述:Multi-Phase PWM Controller
ISL6244CR 功能描述:IC REG CTRLR BUCK PWM 32-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)