The MAX1845 is a dual PWM controller configured for step-down (buck) topologies that provides high efficiency, excellent transient response, and high DC output accuracy necessary for stepping down high-voltage batteries to generate low-voltage chipset and RAM power supplies in notebook computers. The CS_ inputs can be used with low-side sense resistors to provide accurate current limits or can be connected to LX_, using low-side MOSFETs as current-sense elements. The on-demand PWM controllers are free running, constant on-time with input feed-forward. This configuration provides ultra-fast transient response, wide input-output differential range, low supply current, and tight load-regulation characteristics. The MAX1845 is simple and easy to compensate. Single-stage buck conversion allows the MAX1845 to directly step down high-voltage batteries for the highest possible efficiency. Alternatively, two-stage conversion (stepping down the 5V system supply instead of the battery at a higher switching frequency) allows the minimum possible physical size. The MAX1845 is intended for generating chipset, DRAM, CPU I/O, or other low-voltage supplies down to 1V. For a single-output version, refer to the MAX1844 data sheet. The MAX1845 is available in 28-pin QSOP and 36-pin thin QFN packages.
语言 | 下载文件 | 备注 |
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英文 | MAX1845.pdf | Rev 2; 03/2003 |
Part Number | VIN (V) | VIN (V) | VOUT1 (V) | VOUT1 (V) | Preset VOUT (V) | Output Adjust. Method | IOUT1 (A) | Switch Type | Synchronous Switching | DC-DC Outputs | Oper. Freq. (kHz) | Package/Pins | Budgetary Price |
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min | max | min | max | max | See Notes | ||||||||
MAX1845 | 2 | 28 | 1 | 5.5 |
|
| 10 | External | Yes | 2 | 540 |
| $1.57 @1k |
型号 | 状况 | 推荐替代产品 | 封装 | 温度 | RoHS/无铅 |
---|---|---|---|---|---|
MAX1845EEI | 停止供货 | QSOP,;28引脚;61.9mm² | -40°C至+85°C | RoHS/无铅:否 | |
MAX1845EEI+ | 生产中 | QSOP,;28引脚;61.9mm² | -40°C至+85°C | RoHS/无铅:无铅 | |
MAX1845EEI+T | 生产中 | QSOP,;28引脚;61.9mm² | -40°C至+85°C | RoHS/无铅:无铅 | |
MAX1845EEI-T | 停止供货 | MAX1845EEI+T | QSOP;28引脚 | -40°C至+85°C | 参考数据资料 |
MAX1845ETX | 停止供货 | MAX1845ETX+ | TQFN,;36引脚;37.2mm² | -40°C至+85°C | RoHS/无铅:否 |
MAX1845ETX+ | 生产中 | TQFN,;36引脚;37.2mm² | -40°C至+85°C | RoHS/无铅:无铅 | |
MAX1845ETX+T | 生产中 | TQFN,;36引脚;37.2mm² | -40°C至+85°C | RoHS/无铅:无铅 | |
MAX1845ETX-T | 停止供货 | MAX1845ETX+T | QFN;36引脚 | -40°C至+85°C | 参考数据资料 |