- 您现在的位置：买卖IC网 > PDF目录80128 > LM2576-12MDC (NATIONAL SEMICONDUCTOR CORP) 7.5 A SWITCHING REGULATOR, 63 kHz SWITCHING FREQ-MAX, UUC PDF资料下载
参数资料
| 型号： | LM2576-12MDC |
| 厂商： | NATIONAL SEMICONDUCTOR CORP |
| 元件分类： | 稳压器 |
| 英文描述： | 7.5 A SWITCHING REGULATOR, 63 kHz SWITCHING FREQ-MAX, UUC |
| 封装： | DIE |
| 文件页数： | 10/27页 |
| 文件大小： | 741K |
| 代理商： | LM2576-12MDC |
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页当前第10页第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
Additional Applications (Continued)
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 3A 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.
Definition of Terms
BUCK REGULATOR
A switching regulator topology in which a higher voltage is
converted to a lower voltage. Also known as a step-down
switching regulator.
BUCK-BOOST REGULATOR
A switching regulator topology in which a positive voltage is
converted to a negative voltage without a transformer.
DUTY CYCLE (D)
Ratio of the output switch’s on-time to the oscillator period.
CATCH DIODE OR CURRENT STEERING DIODE
The diode which provides a return path for the load current
when the LM2576 switch is OFF.
EFFICIENCY (
η)
The proportion of input power actually delivered to the load.
CAPACITOR EQUIVALENT SERIES RESISTANCE (ESR)
The purely resistive component of a real capacitor’s imped-
ance (see
Figure 16). It causes power loss resulting in ca-
pacitor heating, which directly affects the capacitor’s operat-
ing lifetime. When used as a switching regulator output filter,
higher ESR values result in higher output ripple voltages.
DS011476-17
Note: Complete circuit not shown (see
Figure 10).
FIGURE 13. Undervoltage Lockout
for Buck-Boost Circuit
DS011476-18
Note: Complete circuit not shown.
FIGURE 14. Delayed Startup
DS011476-19
FIGURE 15. 1.2V to 55V Adjustable 3A Power Supply with Low Output Ripple
DS011476-20
FIGURE 16. Simple Model of a Real Capacitor
www.national.com
18
相关PDF资料 |
PDF描述 |
|---|---|
| LSN-5/15-D12J | 1-OUTPUT 75 W DC-DC REG PWR SUPPLY MODULE |
| LES015YGN19 | 1-OUTPUT 15 W DC-DC REG PWR SUPPLY MODULE |
| LES020ZG-3NN2 | 1-OUTPUT 15 W DC-DC REG PWR SUPPLY MODULE |
| LSN-1.25/10-D3B | 1-OUTPUT DC-DC REG PWR SUPPLY MODULE |
| LSN-2.5/10-D3B | 1-OUTPUT 25 W DC-DC REG PWR SUPPLY MODULE |
相关代理商/技术参数 |
参数描述 |
|---|---|
| LM2576-12WT | 功能描述:直流/直流开关调节器 3A Step-Down SMPS Regulator (ROHS Compliant) RoHS:否 制造商:International Rectifier 最大输入电压:21 V 开关频率:1.5 MHz 输出电压:0.5 V to 0.86 V 输出电流:4 A 输出端数量: 最大工作温度: 安装风格:SMD/SMT 封装 / 箱体:PQFN 4 x 5 |
| LM2576-12WU | 功能描述:直流/直流开关调节器 3A Step-Down SMPS Regulator (ROHS Compliant) RoHS:否 制造商:International Rectifier 最大输入电压:21 V 开关频率:1.5 MHz 输出电压:0.5 V to 0.86 V 输出电流:4 A 输出端数量: 最大工作温度: 安装风格:SMD/SMT 封装 / 箱体:PQFN 4 x 5 |
| LM2576-12WU TR | 功能描述:直流/直流开关调节器 3A Step-Down SMPS Regulator (ROHS Compliant) RoHS:否 制造商:International Rectifier 最大输入电压:21 V 开关频率:1.5 MHz 输出电压:0.5 V to 0.86 V 输出电流:4 A 输出端数量: 最大工作温度: 安装风格:SMD/SMT 封装 / 箱体:PQFN 4 x 5 |
| LM2576-15 | 制造商:MOTOROLA 制造商全称:Motorola, Inc 功能描述:Easy Switcher 3.0A Step-Down Voltage Regulator |
| LM2576-15BT | 制造商:未知厂家 制造商全称:未知厂家 功能描述:Voltage-Mode SMPS Controller |
发布紧急采购，3分钟左右您将得到回复。