- 您现在的位置：买卖IC网 > PDF目录20486 > LMZ14201EVAL/NOPB (National Semiconductor)EVAL BOARD FOR LMZ14201 PDF资料下载
参数资料
| 型号： | LMZ14201EVAL/NOPB |
| 厂商： | National Semiconductor |
| 文件页数： | 17/27页 |
| 文件大小： | 0K |
| 描述： | EVAL BOARD FOR LMZ14201 |
| 产品培训模块： | SIMPLE SWITCHER Power Modules |
| 标准包装： | 1 |
| 系列： | SIMPLE SWITCHER® |
| 主要目的： | DC/DC，步降 |
| 输出及类型： | 1，非隔离 |
| 输出电压： | 3.3V |
| 电流 - 输出： | 1A |
| 输入电压： | 6 ~ 24 V |
| 稳压器拓扑结构： | 降压 |
| 频率 - 开关： | 最高 1MHz |
| 板类型： | 完全填充 |
| 已供物品： | 板 |
| 已用 IC / 零件： | LMZ14201 |
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页第11页第12页第13页第14页第15页第16页当前第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
LMZ14201
www.ti.com
SNVS649F – JANUARY 2010 – REVISED OCTOBER 2013
Additional Features
OUTPUT OVER-VOLTAGE COMPARATOR
The voltage at FB is compared to a 0.92V internal reference. If FB rises above 0.92V the on-time is immediately
terminated. This condition is known as over-voltage protection (OVP). It can occur if the input voltage is
increased very suddenly or if the output load is decreased very suddenly. Once OVP is activated, the top
MOSFET on-times will be inhibited until the condition clears. Additionally, the synchronous MOSFET will remain
on until inductor current falls to zero.
CURRENT LIMIT
Current limit detection is carried out during the off-time by monitoring the current in the synchronous MOSFET.
Referring to the Functional Block Diagram, when the top MOSFET is turned off, the inductor current flows
through the load, the PGND pin and the internal synchronous MOSFET. If this current exceeds 2.0 (typical) the
current limit comparator disables the start of the next on-time period. The next switching cycle will occur only if
the FB input is less than 0.8V and the inductor current has decreased below 2.0A. Inductor current is monitored
during the period of time the synchronous MOSFET is conducting. So long as inductor current exceeds 2.0A,
further on-time intervals for the top MOSFET will not occur. Switching frequency is lower during current limit due
to the longer off-time. It should also be noted that current limit is dependent on both duty cycle and temperature
as illustrated in the graphs in the Typical Performance Characteristics section.
THERMAL PROTECTION
The junction temperature of the LMZ14201 should not be allowed to exceed its maximum ratings. Thermal
protection is implemented by an internal Thermal Shutdown circuit which activates at 165 °C (typ) causing the
device to enter a low power standby state. In this state the main MOSFET remains off causing V O to fall, and
additionally the CSS capacitor is discharged to ground. Thermal protection helps prevent catastrophic failures for
accidental device overheating. When the junction temperature falls back below 145 °C (typ Hyst = 20 °C) the SS
pin is released, V O rises smoothly, and normal operation resumes.
Applications requiring maximum output current especially those at high input voltage may require application
derating at elevated temperatures.
ZERO COIL CURRENT DETECTION
The current of the lower (synchronous) MOSFET is monitored by a zero coil current detection circuit which
inhibits the synchronous MOSFET when its current reaches zero until the next on-time. This circuit enables the
DCM operating mode, which improves efficiency at light loads.
PRE-BIASED STARTUP
The LMZ14201 will properly start up into a pre-biased output. This startup situation is common in multiple rail
logic applications where current paths may exist between different power rails during the startup sequence. The
following scope capture shows proper behavior during this event.
Figure 35. Pre-Biased Startup
OUTPUT
VOLTAGE
2V PRE-BIAS
OUTPUT
CURRENT
ENABLE
3.3V OUTPUT
1.0 V/Div
0.5 A/Div
2.0 V/Div
1 ms/Div
Copyright ? 2010–2013, Texas Instruments Incorporated
Product Folder Links: LMZ14201
Submit Documentation Feedback
17
相关PDF资料 |
PDF描述 |
|---|---|
| RH-1505D/HP | CONV DC/DC 1W 15VIN +/-05VOUT |
| 345-060-520-201 | CARDEDGE 60POS DUAL .100 GREEN |
| A3940KLWTR-T | IC CTRLR MOSFET FULL 28-SOIC |
| RMA06DTMS | CONN EDGECARD 12POS R/A .125 SLD |
| MIC4424BN | IC DRIVER MOSFET 3A DUAL 8DIP |
相关代理商/技术参数 |
参数描述 |
|---|---|
| LMZ14201EXT | 制造商:NSC 制造商全称:National Semiconductor 功能描述:1A SIMPLE SWITCHER? Power Module with 42V Maximum Input Voltage for Military and Rugged Applications |
| LMZ14201EXTEVAL/NOPB | 功能描述:电源管理IC开发工具 LMZ14201EXT EVAL BOARD RoHS:否 制造商:Maxim Integrated 产品:Evaluation Kits 类型:Battery Management 工具用于评估:MAX17710GB 输入电压: 输出电压:1.8 V |
| LMZ14201EXTTZ | 制造商:NSC 制造商全称:National Semiconductor 功能描述:1A SIMPLE SWITCHER? Power Module with 42V Maximum Input Voltage for Military and Rugged Applications |
| LMZ14201EXTTZ/NOPB | 功能描述:直流/直流开关转换器 1A SIMPLE SWITCHER POWER MOD, 42V MAX RoHS:否 制造商:STMicroelectronics 最大输入电压:4.5 V 开关频率:1.5 MHz 输出电压:4.6 V 输出电流:250 mA 输出端数量:2 最大工作温度:+ 85 C 安装风格:SMD/SMT |
| LMZ14201EXTTZE | 制造商:NSC 制造商全称:National Semiconductor 功能描述:1A SIMPLE SWITCHER? Power Module with 42V Maximum Input Voltage for Military and Rugged Applications |
发布紧急采购，3分钟左右您将得到回复。