参数资料
型号: LTM8020EV#PBF
厂商: Linear Technology
文件页数: 9/16页
文件大小: 0K
描述: IC DC/DC UMODULE 200MA 21-LGA
产品培训模块: LTM802x High Voltage μModule Switching Regulators
Power Module vs. Discrete DC to DC
µModule® Family of EN55022 Class B Certified Regulators
软件下载: LTM8020 Spice Model
产品目录绘图: LTM8020
设计资源: DC1194A Design Files
LTM8020EV#PBF Footprint.bxl
特色产品: μModule Products
标准包装: 260
系列: µModule®
类型: 非隔离(POL)
输出数: 1
电压 - 输入(最小): 4V
电压 - 输入(最大): 36V
Voltage - Output 1: 1.25 ~ 5 V
电流 - 输出(最大): 200mA
安装类型: 表面贴装
封装/外壳: 21-LGA
尺寸/尺寸: 0.25" L x 0.25" W x 0.09" H(6.3mm x 6.3mm x 2.3mm)
包装: 托盘
工作温度: -40°C ~ 85°C
产品目录页面: 2711 (CN2011-ZH PDF)
LTM8020
APPLICATIONS INFORMATION
PCB Layout
Most of the headaches associated with PCB layout have
been alleviated or even eliminated by the high level of
integration of the LTM8020. The LTM8020 is never-the-
less a switching power supply, and care must be taken to
minimize EMI and ensure proper operation. Even with the
high level of integration, you may fail to achieve specified
operation with a haphazard or poor layout. See Figure 3
for a suggested layout.
Ensure that the grounding and heat sinking are acceptable.
A few rules to keep in mind are:
1. Place the C IN capacitor as close as possible to the V IN
and GND connection of the LTM8020.
2. Place the C OUT capacitor as close as possible to the
V OUT and GND connection of the LTM8020.
3. Place the C IN and C OUT capacitors such that their
ground current flows directly adjacent or underneath
the LTM8020.
4. Connect all of the GND connections to as large a copper
pour or plane area as possible on the top layer. Avoid
breaking the ground connection between the external
components and the LTM8020.
5. The copper pours also serve as the heat sink for the
LTM8020. Place several vias in the GND plane to act as
heat pipes to other layers of the printed circuit board.
Positive-to-Negative Voltage Regulation
The LTM8020 can generate a negative output by tying the
V OUT pads to system ground and connecting GND as shown
in the Typical Applications section. In this configuration,
SHDN must be level shifted or referenced to GND, and the
available output current may be reduced.
Hot-Plugging Safely
The small size, robustness and low impedance of ceramic
capacitors make them an attractive option for the input
bypass capacitor of LTM8020. However, these capacitors
can cause problems if the LTM8020 is plugged into a live
supply (see Linear Technology Application Note 88 for
a complete discussion). The low loss ceramic capacitor
combined with stray inductance in series with the power
source forms an under damped tank circuit, and the volt-
age at the V IN pin of the LTM8020 can ring to twice the
nominal input voltage, possibly exceeding the LTM8020’s
rating and damaging the part. If the input supply is poorly
controlled or the user will be plugging the LTM8020 into
an energized supply, the input network should be designed
to prevent this overshoot. Figure 4 shows the waveforms
that result when an LTM8020 circuit is connected to a 24V
supply through six feet of 24-gauge twisted pair. The first
plot is the response with a 2.2μF ceramic capacitor at the
input. The input voltage rings as high as 35V and the input
current peaks at 20A. One method of damping the tank
circuit is to add another capacitor with a series resistor to
V IN
V OUT
the circuit. In Figure 4b an aluminum electrolytic capacitor
has been added. This capacitor’s high equivalent series
SHDN
C IN
BIAS
C OUT
resistance damps the circuit and eliminates the voltage
overshoot. The extra capacitor improves low frequency
ripple filtering and can slightly improve the efficiency of the
ADJ
circuit, though it is likely to be the largest component in the
circuit. An alternative solution is shown in Figure 4c. A 1 Ω
COPPER
R ADJ
GND
VIAs TO GND PLANE
8020 F03
resistor is added in series with the input to eliminate the
voltage overshoot (it also reduces the peak input current).
Figure 3. Layout Showing Suggested External
Components, GND Plane and Thermal Vias
A 0.1μF capacitor improves high frequency filtering. This
solution is smaller and less expensive than the electrolytic
capacitor. For high input voltages its impact on efficiency
is minor, reducing efficiency less than one-half percent for
a 5V output at full load operating from 24V.
8020fd
9
相关PDF资料
PDF描述
LTC4309IGN#PBF IC BUS BUFFER 2-WIRE 16-SSOP
FMC13DRYN CONN EDGECARD 26POS DIP .100 SLD
V375C5H100BG CONVERTER MOD DC/DC 5V 100W
GRM319F51E474ZA01D CAP CER 0.47UF 25V Y5V 1206
V375C5H100B CONVERTER MOD DC/DC 5V 100W
相关代理商/技术参数
参数描述
LTM8020IV#PBF 功能描述:IC DC/DC UMODULE 200MA 21-LGA RoHS:是 类别:电源 - 板载 >> DC DC Converters 系列:µModule® 设计资源:VI-200, VI-J00 Design Guide, Appl Manual 标准包装:1 系列:* 类型:隔离 输出数:1 电压 - 输入(最小):55V 电压 - 输入(最大):100V Voltage - Output 1:5.8V Voltage - Output 2:- Voltage - Output 3:- 电流 - 输出(最大):* 电源(瓦) - 制造商系列:100W 电压 - 隔离:* 特点:* 安装类型:通孔 封装/外壳:9 针半砖 BusMod 尺寸/尺寸:2.36" L x 2.28" W x 1.08" H(59.9mm x 57.9mm x 27.4mm) 包装:散装 工作温度:-25°C ~ 100°C 效率:* 电源(瓦特)- 最大:*
LTM8020IV#PBF 制造商:Linear Technology 功能描述:DC/DC Controller LTC 制造商:Linear Technology 功能描述:IC, DC/DC MOD REGULATOR, 450kHz, LGA-21
LTM8020IVPBF 制造商:Linear Technology 功能描述:200mA 36V DC/DC uModule Regulator LGA21
LTM8020IV-PBF 制造商:LINER 制造商全称:Linear Technology 功能描述:200mA, 36V DC/DC μModule
LTM8020MPV 制造商:LINER 制造商全称:Linear Technology 功能描述:200mA, 36V DC/DC μModule