- 您现在的位置：买卖IC网 > PDF目录79843 > LMX2575MX-ADJ (NATIONAL SEMICONDUCTOR CORP) 3.2 A SWITCHING REGULATOR, 63 kHz SWITCHING FREQ-MAX, PDSO24 PDF资料下载
参数资料
| 型号： | LMX2575MX-ADJ |
| 厂商： | NATIONAL SEMICONDUCTOR CORP |
| 元件分类： | 稳压器 |
| 英文描述： | 3.2 A SWITCHING REGULATOR, 63 kHz SWITCHING FREQ-MAX, PDSO24 |
| 封装： | SMT-24 |
| 文件页数： | 11/30页 |
| 文件大小： | 676K |
| 代理商： | LMX2575MX-ADJ |
第1页第2页第3页第4页第5页第6页第7页第8页第9页第10页当前第11页第12页第13页第14页第15页第16页第17页第18页第19页第20页第21页第22页第23页第24页第25页第26页第27页第28页第29页第30页
Additional Applications (Continued)
UNDERVOLTAGE LOCKOUT
In some applications it is desirable to keep the regulator off
until the input voltage reaches a certain threshold. An under-
voltage lockout circuit which accomplishes this task is shown
in
Figure 12, while Figure 13 shows the same circuit applied
to a buck-boost configuration. These circuits keep the regu-
lator off until the input voltage reaches a predetermined
level.
V
TH ≈ VZ1 +2VBE (Q1)
DELAYED STARTUP
The ON /OFF pin can be used to provide a delayed startup
feature as shown in
Figure 14. With an input voltage of 20V
and for the part values shown, the circuit provides approxi-
mately 10 ms of delay time before the circuit begins switch-
ing. Increasing the RC time constant can provide longer de-
lay times. But excessively large RC time constants can
cause problems with input voltages that are high in 60 Hz or
120 Hz ripple, by coupling the ripple into the ON /OFF pin.
ADJUSTABLE OUTPUT, LOW-RIPPLE
POWER SUPPLY
A 1A power supply that features an adjustable output voltage
is shown in
Figure 15. An additional L-C filter that reduces
the output ripple by a factor of 10 or more is included in this
circuit.
DS011475-16
Typical Load Current
200 mA for VIN = 5.2V
500 mA for VIN = 7V
Note: Pin numbers are for TO-220 package.
FIGURE 11. Negative Boost
DS011475-17
Note: Complete circuit not shown.
Note: Pin numbers are for the TO-220 package.
FIGURE 12. Undervoltage Lockout for Buck Circuit
DS011475-18
Note: Complete circuit not shown (see
Figure 10).
Note: Pin numbers are for the TO-220 package.
FIGURE 13. Undervoltage Lockout
for Buck-Boost Circuit
DS011475-19
Note: Complete circuit not shown.
Note: Pin numbers are for the TO-220 package.
FIGURE 14. Delayed Startup
www.national.com
19
相关PDF资料 |
PDF描述 |
|---|---|
| LS1001-7RD3B2 | 1-OUTPUT 100 W AC-DC REG PWR SUPPLY MODULE |
| LS1001-9PB2 | 1-OUTPUT 100 W AC-DC REG PWR SUPPLY MODULE |
| LS1001-9PD6B2 | 1-OUTPUT 100 W AC-DC REG PWR SUPPLY MODULE |
| LS1301-7EPTB2 | 1-OUTPUT 100 W AC-DC REG PWR SUPPLY MODULE |
| LS1301-7PD6B2 | 1-OUTPUT 100 W AC-DC REG PWR SUPPLY MODULE |
相关代理商/技术参数 |
参数描述 |
|---|---|
| LMX2581 | 制造商:TI 制造商全称:Texas Instruments 功能描述:LMX2581 Wideband Frequency Synthesizer with Integrated VCO |
| LMX2581EVAL/NOPB | 功能描述:时钟和定时器开发工具 LMX2581 EVAL MOD RoHS:否 制造商:Texas Instruments 产品:Evaluation Modules 类型:Clock Conditioners 工具用于评估:LMK04100B 频率:122.8 MHz 工作电源电压:3.3 V |
| LMX2581EVM | 功能描述:LMX2581 - Timing, Frequency Synthesizer Evaluation Board 制造商:texas instruments 系列:- 零件状态:有效 主要用途:计时，频率合成器 嵌入式:- 使用的 IC/零件:LMX2581 主要属性:带 VCO 的单路分数-N PLL 辅助属性:- 所含物品:板 标准包装:1 |
| LMX2581SQ | 制造商:TI 制造商全称:Texas Instruments 功能描述:LMX2581 Wideband Frequency Synthesizer with Integrated VCO |
| LMX2581SQ/NOPB | 制造商:Texas Instruments 功能描述:IC FREQ SYNTHESIZER VCO 32WQFN 制造商:Texas Instruments 功能描述:CLOCK GENERATION/OTHER IC |
发布紧急采购，3分钟左右您将得到回复。