- 您现在的位置：买卖IC网 > PDF目录1773 > A4490EES-T (Allegro Microsystems Inc)IC REG BUCK ADJ 1.5A TRPL 20QFN PDF资料下载
参数资料
| 型号： | A4490EES-T |
| 厂商： | Allegro Microsystems Inc |
| 文件页数： | 14/17页 |
| 文件大小： | 0K |
| 描述： | IC REG BUCK ADJ 1.5A TRPL 20QFN |
| 标准包装： | 92 |
| 类型： | 降压（降压） |
| 输出类型： | 可调式 |
| 输出数： | 3 |
| 输出电压： | 可调 |
| 输入电压： | 4.5 V ~ 34 V |
| PWM 型： | 电流模式 |
| 频率 - 开关： | 550kHz |
| 电流 - 输出： | 1.5A |
| 同步整流器： | 无 |
| 工作温度： | -40°C ~ 85°C |
| 安装类型： | 表面贴装 |
| 封装/外壳： | 20-WFQFN 裸露焊盘 |
| 包装： | 管件 |
| 供应商设备封装： | 20-QFN 裸露焊盘（4x4） |
| 配用： | 620-1388-ND - BOARD EVAL FOR A4490 |
| 其它名称： | A4490SES-T A4490SES-T-ND |
A4490
Triple Output Step-Down Switching Regulator
This calculation assumes no thermal influence from other compo-
nents. If possible, it is advisable to mount the flyback diodes on
the reverse side of the printed circuit board. Ensure low imped-
ance electrical connections are implemented between board
layers.
PCB Layout Guidelines The ground plane is largely dictated
by the thermal requirements described in the previous section.
The ground referenced power components should be referenced
to a star ground, located away from the A4490 to minimize
ground bounce issues.
A small, local, relatively quiet ground plane near the A4490 should
be used for the ground referenced support components, to mini-
mize interference effects of ground noise from the power circuitry.
Figure 4 illustrates the recommended grounding architecture.
To avoid ground bounce and offset issues, it is highly recom-
mended that the ground referenced feedback resistors (R2, R4,
and R6) should be connected as close to the GND connection of
the A4490 as possible.
A local quiet ground plane around these components can be
implemented, however, this ground plane should have a high
impedance connection to the star connection of the power stages.
If a ground plane is used, it is recommended that it does not
overlap the switching nodes (LX1, LX2, and LX3) to avoid the
possibility of noise pick-up. To minimize the possibility of noise
injection issues, it is recommended to isolate the ground plane
around high impedance nodes such as: FBx, ENBx and CPOR.
In terms of grounding the power components, a star connection
should be made to minimize the ground loop impedances. Note
that although a ground plane may be required to meet the thermal
characteristics of the solution it is still imperative to implement
a ground star connection for the power components. The ground
A4490 Support
Components
Power Circuitry
for the charge pump (PGND) should be connected to the thermal
vias.
A4490
Cin
D
Cout
Figures 5 and 6 below illustrates the importance of keeping the
ground connections as short as possible and forming good star
Local “Quiet’
Ground Plane
GND
PGND
Star Connection
connections.
Figure 5 also illustrates the current conduction paths during the
Thermal Vias
Internal Ground Plane
Figure 4. Ground plane configurations
on-cycle of the switching FET. The following points should be
noted:
? The capacitor C IN should be placed as close as possible to the
VBB terminals. The capacitance should be split between the VBB
terminals for V REG1 and V REG3 and the VBB terminal for V REG2 .
V BB
Q
LX
L
V REG
V BB
Q
LX
L
V REG
D
D
C IN
C OUT
C IN
C OUT
Star Connection
Figure 5. FET on-cycle current conduction paths
R LOAD
Star Connection
Figure 6. FET off-cycle current conduction paths
R LOAD
Allegro MicroSystems, LLC
115 Northeast Cutoff
Worcester, Massachusetts 01615-0036 U.S.A.
1.508.853.5000; www.allegromicro.com
14
相关PDF资料 |
PDF描述 |
|---|---|
| A4491EESTR-T | IC REG BUCK ADJ 2.2A TRPL 20QFN |
| A4931MET-T | IC DC MOTOR PREDRIVER 3PH 28QFN |
| A4934GLPTR-T | IC BLDC DVR 3PHASE 16-ETSSOP |
| A4936METTR-T | IC DC MOTOR PREDRIVER 3PH 32QFN |
| A4938EETTR-T | IC DC MOTOR PREDRIVER 3PH 28-QFN |
相关代理商/技术参数 |
参数描述 |
|---|---|
| A4490EESTRT | 制造商:ALLEGRO 功能描述:Pb Free |
| A4490EESTR-T | 功能描述:IC REG BUCK ADJ 1.5A TRPL 20QFN RoHS:是 类别:集成电路 (IC) >> PMIC - 稳压器 - DC DC 开关稳压器 系列:- 标准包装:250 系列:- 类型:降压（降压） 输出类型:固定 输出数:1 输出电压:1.2V 输入电压:2.05 V ~ 6 V PWM 型:电压模式 频率 - 开关:2MHz 电流 - 输出:500mA 同步整流器:是 工作温度:-40°C ~ 85°C 安装类型:表面贴装 封装/外壳:6-UFDFN 包装:带卷 (TR) 供应商设备封装:6-SON（1.45x1） 产品目录页面:1032 (CN2011-ZH PDF) 其它名称:296-25628-2 |
| A4491 | 制造商:ALLEGRO 制造商全称:Allegro MicroSystems 功能描述:Designed to provide the power supply requirements of printers, office automation, industrial, and portable equipment, the A4491 provides three high current, |
| A4491EESTR-T | 功能描述:IC REG BUCK ADJ 2.2A TRPL 20QFN RoHS:是 类别:集成电路 (IC) >> PMIC - 稳压器 - DC DC 开关稳压器 系列:- 标准包装:50 系列:- 类型:升压（升压） 输出类型:可调式 输出数:1 输出电压:5 V ~ 25 V 输入电压:2.3 V ~ 5.5 V PWM 型:电流模式 频率 - 开关:600kHz，1.2MHz 电流 - 输出:1A 同步整流器:无 工作温度:-40°C ~ 85°C 安装类型:表面贴装 封装/外壳:8-TSSOP，8-MSOP（0.118"，3.00mm 宽） 包装:管件 供应商设备封装:8-MSOP |
| A4492 | 制造商:ALLEGRO 制造商全称:Allegro MicroSystems 功能描述:Designed to provide the power supply requirements for automotive applications, the A4492 provides three high current, high performance, switching regulator outputs with independent soft start. |
发布紧急采购，3分钟左右您将得到回复。