参数资料
型号: ISL6334ACRZ-TR5368
厂商: Intersil
文件页数: 22/31页
文件大小: 0K
描述: IC CTRLR PWM 4PHASE BUCK 40QFN
标准包装: 4,000
应用: 控制器,Intel VR11.1
输入电压: 3 V ~ 12 V
输出数: 1
输出电压: 0.5 V ~ 1.6 V
工作温度: 0°C ~ 70°C
安装类型: 表面贴装
封装/外壳: 40-VFQFN 裸露焊盘
供应商设备封装: 40-QFN(6x6)
包装: 带卷 (TR)
ISL6334AR5368
VR_RDY
OUTPUT CURRENT
UV
50%
0A
DAC
SOFT-START, FAULT
AND CONTROL LOGIC
+
OC
-
105μA
I AVG
OUTPUT VOLTAGE
VDIFF
+
-
OV
+
OC
-
1.11V
IMON
0V
2ms/DIV
FIGURE 11. OVERCURRENT BEHAVIOR IN HICCUP MODE.
F SW = 500kHz
VID + 0.175V
FIGURE 10. VR_RDY AND PROTECTION CIRCUITRY
Overcurrent Protection
ISL6334AR5368 has two levels of overcurrent protection.
Each phase is protected from a sustained overcurrent
condition by limiting its peak current, while the combined
phase currents are protected on an instantaneous basis.
In instantaneous protection mode, ISL6334AR5368 utilizes
the sensed average current I AVG to detect an overcurrent
condition. See “Channel-Current Balance” on page 15 for
more details on how the average current is measured. The
average current is continually compared with a constant
105μA reference current, as shown in Figure 10. Once the
average current exceeds the reference current, a
comparator triggers the converter to shutdown.
The current out of IMON pin is equal to the sensed average
current I AVG . With a resistor from IMON to GND, the voltage
at IMON will be proportional to the sensed average current
and the resistor value. The ISL6334AR5368 continuously
monitors the voltage at IMON pin. If the voltage at IMON pin is
higher than 1.11V, a comparator triggers the overcurrent
shutdown. By increasing the resistor between IMON and
GND, the overcurrent protection threshold can be adjusted to
be less than 105μA. For example, the overcurrent threshold
for the sensed average current I AVG can be set to 95μA by
using a 11.8k Ω resistor from IMON to GND.
At the beginning of overcurrent shutdown, the controller
places all PWM signals in a high-impedance state within
20ns, commanding the Intersil MOSFET driver ICs to turn off
both upper and lower MOSFETs. The system remains in this
state a period of 4096 switching cycles. If the controller is still
enabled at the end of this wait period, it will attempt a
soft-start. If the fault remains, the trip-retry cycles will
continue indefinitely (as shown in Figure 11) until either
controller is disabled or the fault is cleared. Note that the
22
energy delivered during trip-retry cycling is much less than
during full-load operation, so there is no thermal hazard
during this kind of operation.
For the individual channel overcurrent protection,
ISL6334AR5368 continuously compares the sensed current
signal of each channel with the 129μA reference current. If
one channel current exceeds the reference current,
ISL6334AR5368 will pull PWM signal of this channel to low
for the rest of the switching cycle. This PWM signal can be
turned on next cycle if the sensed channel current is less
than the 129μA reference current. The peak current limit of
individual channel will not trigger the converter to shutdown.
Thermal Monitoring (VR_HOT/VR_FAN)
There are two thermal signals to indicate the temperature
status of the voltage regulator: VR_HOT and VR_FAN. Both
VR_FAN and VR_HOT pins are open-drain outputs, and
external pull-up resistors are required. Those signals are
valid only after the controller is enabled.
The VR_FAN signal indicates that the temperature of the
voltage regulator is high and more cooling airflow is needed.
The VR_HOT signal can be used to inform the system that
the temperature of the voltage regulator is too high and the
CPU should reduce its power consumption. The VR_HOT
signal may be tied to the CPU’s PROC_HOT signal.
The diagram of thermal monitoring function block is shown in
Figure 12. One NTC resistor should be placed close to the
power stage of the voltage regulator to sense the operational
temperature, and one pull-up resistor is needed to form the
voltage divider for the TM pin. As the temperature of the power
stage increases, the resistance of the NTC will reduce, resulting
in the reduced voltage at the TM pin. Figure 13 shows the TM
voltage over the temperature for a typical design with a
recommended 6.8k Ω NTC (P/N: NTHS0805N02N6801 from
Vishay) and 1k Ω resistor RTM1. We recommend using those
resistors for the accurate temperature compensation.
FN6839.2
September 7, 2010
相关PDF资料
PDF描述
LT3015IMSE#PBF IC REG LDO NEG ADJ 1.5A 12MSOP
LT3015ET#PBF IC REG LDO NEG ADJ 1.5A 5-TO220
ESM24DRMD CONN EDGECARD 48POS .156 WW
GSC50DREI-S13 CONN EDGECARD 100PS .100 EXTEND
EL7586ILZ-T7 IC POWER SUPPLY TFT-LCD 20-QFN
相关代理商/技术参数
参数描述
ISL6334ACRZ-TR5453 制造商:Intersil Corporation 功能描述:STD. ISL6334ACRZ-T W/GOLD BOND WIRE ONLY T&R - Tape and Reel
ISL6334AIRZ 功能描述:IC CTRLR PWM 4PHASE BUCK 40-QFN RoHS:是 类别:集成电路 (IC) >> PMIC - 稳压器 - 专用型 系列:- 标准包装:43 系列:- 应用:控制器,Intel VR11 输入电压:5 V ~ 12 V 输出数:1 输出电压:0.5 V ~ 1.6 V 工作温度:-40°C ~ 85°C 安装类型:表面贴装 封装/外壳:48-VFQFN 裸露焊盘 供应商设备封装:48-QFN(7x7) 包装:管件
ISL6334AIRZR5368 功能描述:IC CTRLR PWM 4PHASE BUCK 40QFN RoHS:是 类别:集成电路 (IC) >> PMIC - 稳压器 - 专用型 系列:- 标准包装:43 系列:- 应用:控制器,Intel VR11 输入电压:5 V ~ 12 V 输出数:1 输出电压:0.5 V ~ 1.6 V 工作温度:-40°C ~ 85°C 安装类型:表面贴装 封装/外壳:48-VFQFN 裸露焊盘 供应商设备封装:48-QFN(7x7) 包装:管件
ISL6334AIRZ-T 功能描述:IC CTRLR PWM 4PHASE BUCK 40-QFN RoHS:是 类别:集成电路 (IC) >> PMIC - 稳压器 - 专用型 系列:- 标准包装:43 系列:- 应用:控制器,Intel VR11 输入电压:5 V ~ 12 V 输出数:1 输出电压:0.5 V ~ 1.6 V 工作温度:-40°C ~ 85°C 安装类型:表面贴装 封装/外壳:48-VFQFN 裸露焊盘 供应商设备封装:48-QFN(7x7) 包装:管件
ISL6334AIRZ-TR5368 功能描述:IC CTRLR PWM 4PHASE BUCK 40QFN RoHS:是 类别:集成电路 (IC) >> PMIC - 稳压器 - 专用型 系列:- 标准包装:43 系列:- 应用:控制器,Intel VR11 输入电压:5 V ~ 12 V 输出数:1 输出电压:0.5 V ~ 1.6 V 工作温度:-40°C ~ 85°C 安装类型:表面贴装 封装/外壳:48-VFQFN 裸露焊盘 供应商设备封装:48-QFN(7x7) 包装:管件