参数资料
型号: ISL9440AIRZ
厂商: Intersil
文件页数: 13/20页
文件大小: 0K
描述: IC REG QD BCK/LINEAR SYNC 32-QFN
产品培训模块: Patient Monitoring and Diagnostic Equipment Solutions
Solutions for Test and Measurement Equipment
Solutions for Industrial Control Applications
标准包装: 60
拓扑: 降压(降压)同步(3),线性(LDO)(1)
功能: 任何功能
输出数: 4
频率 - 开关: 600kHz
电压/电流 - 输出 1: 控制器
电压/电流 - 输出 2: 控制器
电压/电流 - 输出 3: 控制器
带 LED 驱动器:
带监控器:
带序列发生器:
电源电压: 4.5 V ~ 24 V
工作温度: -40°C ~ 85°C
安装类型: 表面贴装
封装/外壳: 32-VFQFN 裸露焊盘
供应商设备封装: *
包装: 管件
产品目录页面: 1244 (CN2011-ZH PDF)
ISL9440, ISL9440A, ISL9441
Functional Description
General Description
The ISL9440, ISL9440A and ISL9441 integrate control
circuits for three synchronous buck converters and one
linear controller. The three synchronous bucks operate out of
phase to substantially reduce the input ripple and thus
reduce the input filter requirements. The chip has 3 control
lines (EN1, EN2 and EN3), which provide independent
control for each of the synchronous buck outputs.
The buck PWM controllers employ free-running frequency of
300kHz (ISL9440 and ISL9441) and 600kHz (ISL9440A).
The current mode control scheme with an input voltage feed-
forward ramp input to the modulator provides an excellent
start is done and all the four outputs are up and in
regulations.
Output Voltage Programming
The ISL9440, ISL9440A and ISL9441 use a precision
internal reference voltage to set the output voltage. Based
on this internal reference, the output voltage can thus be set
from 0.8V up to a level determined by the input voltage, the
maximum duty cycle, and the conversion efficiency of the
circuit.
A resistive divider from the output to ground sets the output
voltage of either PWM channel. The center point of the
divider shall be connected to FBx pin. The output voltage
value is determined by Equation 1.
V OUTx = 0.8V ? ---------------------- ?
rejection of input voltage variations and provides simplified
loop compensations.
R1 + R2
? R2 ?
(EQ. 1)
The linear controller can drive either a PNP or PFET to provide
ultra low-dropout regulation with programmable voltages.
Internal 5V Linear Regulator (VCC_5V)
All ISL9440, ISL9440A and ISL9441 functions are internally
powered from an on-chip, low dropout 5V regulator. The
maximum regulator input voltage is 24V. Bypass the
regulator ’s output (VCC_5V) with a 4.7μF capacitor to
ground. The dropout voltage for this LDO is typically 600mV,
so when VIN is greater than 5.6V, VCC_5V is typically 5V.
The ISL9440, ISL9440A and ISL9441 also employ an
undervoltage lockout circuit that disables both regulators
when VCC_5V falls below 4.4V.
The internal LDO can source over 60mA to supply the IC,
power the low side gate drivers and charge the external boot
capacitor. When driving large FETs especially at 300kHz
(ISL9440, ISL9441)/600kHz (ISL9440A) frequency, little or
no regulator current may be available for external loads.
For example, a single large FET with 15nC total gate charge
requires 15nC x 300kHz = 4.5mA (15nC x 600kHz = 9mA).
Also, at higher input voltages with larger FETs, the power
dissipation across the internal 5V will increase. Excessive
dissipation across this regulator must be avoided to prevent
junction temperature rise. Larger FETs can be used with 5V
±10% input applications. The thermal overload protection
circuit will be triggered, if the VCC_5V output is short-circuit.
Connect VCC_5V to V IN for 5V ±10% input applications.
Digital Enable Signals
The typical applications for the ISL9440, ISL9440A and
ISL9441 are using digital sequencing controllers for the
power rails. Using a digital enable rather than an analog soft-
start provides a well controlled method for sequencing up
and down on the power rails.
Soft-Start Operation
The ISL9440, ISL9440A and ISL9441 have a fixed soft-start
time, 1.7ms (TYP). PGOOD will not toggle to high until soft-
13
where R1 is the top resistor of the feedback divider network
and R2 is the resistor connected from FBx to ground.
Out-of-Phase Operation
To reduce input ripple current, Channel 1 and Channel 2
operate 180° out-of-phase, Channel 3 keeps 0 phase degree
with Channel 1. Channel 1 and Channel 2 typically output
higher load compared to Channel 3 because of their stronger
drivers. This reduces the input capacitor ripple current
requirements, reduces power supply-induced noise, and
improves EMI. This effectively helps to lower component cost,
save board space and reduce EMI.
Triple PWMs typically operate in-phase and turn on both upper
FETs at the same time. The input capacitor must then support
the instantaneous current requirements of the three switching
regulators simultaneously, resulting in increased ripple voltage
and current. The higher RMS ripple current lowers the
efficiency due to the power loss associated with the ESR of the
input capacitor. This typically requires more low-ESR capacitors
in parallel to minimize the input voltage ripple and ESR-related
losses, or to meet the required ripple current rating.
With synchronized out-of-phase operation, the high-side
MOSFETs turn on 180° out-of-phase. The instantaneous input
current peaks of both regulators no longer overlap, resulting in
reduced RMS ripple current and input voltage ripple. This
reduces the required input capacitor ripple current rating,
allowing fewer or less expensive capacitors, and reducing the
shielding requirements for EMI. The typical operating curves
show the synchronized 180° out-of-phase operation.
Input Voltage Range
The ISL9440, ISL9440A and ISL9441 are designed to
operate from input supplies ranging from 4.5V to 24V.
For 5V ±10% input applications, ISL9441 is suggested. The
reason is that VIN and VCC_5V Pin should be tied together
for this input application. The early warning function will pull
PGOOD and RST low for ISL9440 and ISL9440A. ISL9441
has not been implemented with early warning function.
FN6383.1
December 5, 2007
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ISL9440AIRZ-T 功能描述:IC REG QD BCK/LINEAR SYNC 32-QFN RoHS:是 类别:集成电路 (IC) >> PMIC - 稳压器 - 线性 + 切换式 系列:- 标准包装:2,500 系列:- 拓扑:降压(降压)同步(2),线性(LDO)(1) 功能:任何功能 输出数:3 频率 - 开关:300kHz 电压/电流 - 输出 1:控制器 电压/电流 - 输出 2:控制器 电压/电流 - 输出 3:控制器 带 LED 驱动器:无 带监控器:无 带序列发生器:是 电源电压:4.5 V ~ 24 V 工作温度:-40°C ~ 85°C 安装类型:* 封装/外壳:28-TSSOP(0.173",4.40mm 宽) 供应商设备封装:* 包装:带卷 (TR) 其它名称:ISL6402IVZ-TTR
ISL9440BEVAL1Z 功能描述:EVAL BOARD 1 FOR ISL9440B RoHS:是 类别:编程器,开发系统 >> 评估板 - DC/DC 与 AC/DC(离线)SMPS 系列:* 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
ISL9440BIRZ 功能描述:IC REG QD BCK/LINEAR SYNC 32-QFN RoHS:是 类别:集成电路 (IC) >> PMIC - 稳压器 - 线性 + 切换式 系列:- 标准包装:2,500 系列:- 拓扑:降压(降压)同步(2),线性(LDO)(1) 功能:任何功能 输出数:3 频率 - 开关:300kHz 电压/电流 - 输出 1:控制器 电压/电流 - 输出 2:控制器 电压/电流 - 输出 3:控制器 带 LED 驱动器:无 带监控器:无 带序列发生器:是 电源电压:4.5 V ~ 24 V 工作温度:-40°C ~ 85°C 安装类型:* 封装/外壳:28-TSSOP(0.173",4.40mm 宽) 供应商设备封装:* 包装:带卷 (TR) 其它名称:ISL6402IVZ-TTR
ISL9440BIRZ-T 功能描述:IC REG QD BCK/LINEAR SYNC 32-QFN RoHS:是 类别:集成电路 (IC) >> PMIC - 稳压器 - 线性 + 切换式 系列:- 标准包装:2,500 系列:- 拓扑:降压(降压)同步(2),线性(LDO)(1) 功能:任何功能 输出数:3 频率 - 开关:300kHz 电压/电流 - 输出 1:控制器 电压/电流 - 输出 2:控制器 电压/电流 - 输出 3:控制器 带 LED 驱动器:无 带监控器:无 带序列发生器:是 电源电压:4.5 V ~ 24 V 工作温度:-40°C ~ 85°C 安装类型:* 封装/外壳:28-TSSOP(0.173",4.40mm 宽) 供应商设备封装:* 包装:带卷 (TR) 其它名称:ISL6402IVZ-TTR
ISL9440CEVAL1Z 功能描述:EVAL BOARD 1 FOR ISL9440C RoHS:是 类别:编程器,开发系统 >> 评估板 - DC/DC 与 AC/DC(离线)SMPS 系列:* 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