参数资料
型号: MAX8717ETI+
厂商: Maxim Integrated Products
文件页数: 20/30页
文件大小: 0K
描述: IC CNTRLR PWR SUP 28-TQFN
标准包装: 60
应用: 控制器,笔记本电脑电源系统
输入电压: 4 V ~ 26 V
输出数: 2
输出电压: 3.3V,5V,1 V ~ 5.5 V
工作温度: 0°C ~ 85°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(5x5)
包装: 管件
Interleaved High-Efficiency, Dual Power-Supply
Controllers for Notebook Computers
V GS ( TH ) > V IN ? RSS ?
The  internal  pulldown  transistor  that  drives  DL_  low  is
robust, with a 0.6 Ω (typ) on-resistance. This helps pre-
vent DL_ from being pulled up due to capacitive cou-
pling from the drain to the gate of the low-side MOSFETs
when the inductor node (LX_) quickly switches from
ground to V IN . Applications with high input voltages and
long inductive driver traces may require additional gate-
to-source capacitance to ensure fast-rising LX_ edges
do not pull up the low-side MOSFETs gate, causing
shoot-through currents. The capacitive coupling
between LX_ and DL_ created by the MOSFET’s gate-to-
drain capacitance (C RSS ), gate-to-source capacitance
(C ISS - C RSS ), and additional board parasitics should not
exceed the following minimum threshold:
? C ?
? C ISS ?
Variation of the threshold voltage may cause problems
in marginal designs. Alternatively, adding a resistor
less than 10 Ω in series with BST_ may remedy the
problem by increasing the turn-on time of the high-side
MOSFET without degrading the turn-off time (Figure 6).
C BYP
V DD
MAX8716
Power-Good Output (PGOOD_)
PGOOD_ is the open-drain output of a comparator that
continuously monitors each SMPS output voltage for
overvoltage and undervoltage conditions. PGOOD_ is
actively held low in shutdown (ON_ = GND), soft-start,
and soft-shutdown. Once the analog soft-start termi-
nates, PGOOD_ becomes high impedance as long as
the output is above 90% of the nominal regulation volt-
age set by FB_. PGOOD_ goes low once the output
drops 10% below its nominal regulation point, an output
overvoltage fault occurs, or ON_ is pulled low. For a
logic-level PGOOD_ output voltage, connect an exter-
nal pullup resistor between PGOOD_ and +5V or +3.3V.
A 100k Ω pullup resistor works well in most applications.
Fault Protection
Output Overvoltage Protection
(MAX8716/MAX8717/MAX8756 Only)
If the output voltage of either SMPS rises above 115%
of its nominal regulation voltage, the corresponding
controller sets its overvoltage fault latch, pulls PGOOD_
low, and forces DL_ high for the corresponding SMPS
controller. The other controller is not affected. If the
condition that caused the overvoltage persists (such as
a shorted high-side MOSFET), the battery fuse will
blow. Cycle V CC below 1V or toggle ON_ to clear the
overvoltage fault latch and restart the SMPS controller.
MAX8717
MAX8756
D BST
FAULT
MAX8757
BST
(R BST )*
POWER-GOOD
0.9 x
1.15 x
PROTECTION
0.7 x
C BST
INPUT (V IN )
INT REF_
INT REF_
INT REF_
INTERNAL FB
DH
N H
LX
L
POR
V DD
DL
N L
TIMER
PGND
(C NL )*
FAULT
LATCH
FAULT
POWER-
GOOD
(R BST )* OPTIONAL—THE RESISTOR LOWERS EMI BY DECREASING
THE SWITCHING-NODE RISE TIME.
(C NL )* OPTIONAL—THE CAPACITOR REDUCES LX TO DL CAPACITIVE
COUPLING THAT CAN CAUSE SHOOT-THROUGH CURRENTS.
Figure 6. Optional Gate-Driver Circuitry
Figure 7. Power-Good and Fault Protection
20
______________________________________________________________________________________
相关PDF资料
PDF描述
AYM18DRMH-S288 CONN EDGECARD 36POS .156 EXTEND
X4043S8IT2 IC SUPERVISOR CPU 4K EE 8-SOIC
ASM18DRMH-S288 CONN EDGECARD 36POS .156 EXTEND
RSM24DSES-S243 CONN EDGECARD 48POS .156 EYELET
X4043S8IT1 IC SUPERVISOR CPU 4K EE 8-SOIC
相关代理商/技术参数
参数描述
MAX8717ETI+ 功能描述:软开关 PWM 控制器 Dual Power-Supply Controller RoHS:否 制造商:Fairchild Semiconductor 输出端数量: 输出电流: 开关频率: 工作电源电压:30 V 电源电流: 最大工作温度:+ 105 C 最小工作温度:- 40 C 安装风格:SMD/SMT 封装 / 箱体:SOIC-8 封装:Reel
MAX8717ETI+T 功能描述:电流和电力监控器、调节器 Dual Power-Supply Controller RoHS:否 制造商:STMicroelectronics 产品:Current Regulators 电源电压-最大:48 V 电源电压-最小:5.5 V 工作温度范围:- 40 C to + 150 C 安装风格:SMD/SMT 封装 / 箱体:HPSO-8 封装:Reel
MAX8717ETI-T 功能描述:电流和电力监控器、调节器 RoHS:否 制造商:STMicroelectronics 产品:Current Regulators 电源电压-最大:48 V 电源电压-最小:5.5 V 工作温度范围:- 40 C to + 150 C 安装风格:SMD/SMT 封装 / 箱体:HPSO-8 封装:Reel
MAX8717EVKIT 制造商:Maxim Integrated Products 功能描述:HIGH-EFFICIENCY DUAL POWER-SUPPLY - Rail/Tube
MAX8718ETA 制造商:Maxim Integrated Products 功能描述:HIGH-VOLTAGE LOW-POWER LINEAR REGU - Rail/Tube