The LM1117MPX-1.8 from Texas Instruments is an 800mA low-dropout linear regulator with 1.8V fixed output, 1.2V dropout at 800mA, and SOT-223 package.<\/p>\n
| \u0627\u0644\u0646\u0648\u0639<\/td>\n | 800mA Low-Dropout Linear Regulator<\/td>\n<\/tr>\n | ||||||||||||||||||||||||||||||||||||||||||||
| \u062c\u0647\u062f \u0627\u0644\u062e\u0631\u062c<\/td>\n | 1.8V (fixed)<\/td>\n<\/tr>\n | ||||||||||||||||||||||||||||||||||||||||||||
| \u062a\u064a\u0627\u0631 \u0627\u0644\u0625\u062e\u0631\u0627\u062c<\/td>\n | 800 mA (max)<\/td>\n<\/tr>\n | ||||||||||||||||||||||||||||||||||||||||||||
| \u062c\u0647\u062f \u0627\u0644\u062a\u0633\u0631\u0628<\/td>\n | 1.2V (typical) @ 800mA; 1.3V (max) @ 800mA<\/td>\n<\/tr>\n | ||||||||||||||||||||||||||||||||||||||||||||
| \u0646\u0637\u0627\u0642 \u062c\u0647\u062f \u0627\u0644\u0625\u062f\u062e\u0627\u0644<\/td>\n | 2.6V to 15V (1.8V + Vdo to 15V)<\/td>\n<\/tr>\n | ||||||||||||||||||||||||||||||||||||||||||||
| Line Regulation<\/td>\n | 0.2% (max)<\/td>\n<\/tr>\n | ||||||||||||||||||||||||||||||||||||||||||||
| Load Regulation<\/td>\n | 0.4% (max)<\/td>\n<\/tr>\n | ||||||||||||||||||||||||||||||||||||||||||||
| \u062a\u064a\u0627\u0631 \u0627\u0644\u062a\u0647\u062f\u0626\u0629<\/td>\n | 5 mA (typical)<\/td>\n<\/tr>\n | ||||||||||||||||||||||||||||||||||||||||||||
| Output Voltage Accuracy<\/td>\n | +\/-1%<\/td>\n<\/tr>\n | ||||||||||||||||||||||||||||||||||||||||||||
| \u0627\u0644\u062d\u0632\u0645\u0629<\/td>\n | SOT-223 (DCY, 4-pin)<\/td>\n<\/tr>\n | ||||||||||||||||||||||||||||||||||||||||||||
| \u062f\u0631\u062c\u0629 \u062d\u0631\u0627\u0631\u0629 \u0627\u0644\u062a\u0634\u063a\u064a\u0644<\/td>\n | 0C to +125C<\/td>\n<\/tr>\n<\/table>\n\u0627\u0644\u0645\u064a\u0632\u0627\u062a<\/h2>\n\u0627\u0644\u062a\u0637\u0628\u064a\u0642\u0627\u062a<\/h2>\nProduct Overview The LM1117MPX-1.8 from Texas Instruments is an 800mA low-dropout linear regulator with 1.8V fixed output, 1.2V dropout at 800mA, and SOT-223 package. Key Specifications Type 800mA Low-Dropout Linear Regulator Output Voltage 1.8V (fixed) Output Current 800 mA (max) Dropout Voltage 1.2V (typical) @ 800mA; 1.3V (max) @ 800mA Input Voltage Range 2.6V to […]<\/p>\n","protected":false},"author":2,"featured_media":0,"comment_status":"open","ping_status":"","sticky":false,"template":"","format":"standard","meta":{"_acf_changed":false,"footnotes":""},"categories":[19,13],"tags":[],"chip_brand":[138],"class_list":["post-6962","post","type-post","status-publish","format-standard","hentry","category-analog-linear-ics","category-integrated-circuits-ics","chip_brand-ti"],"acf":{"brief_explanation":"LDO Regulator, 1.8V, 800mA, 1.2V Vdo, SOT-223","date_code":"","package_case":"SOT-223-4 (6.5 x 3.5 x 1.6 mm, 2.3mm pitch)","in_stock":56789,"datasheet":"https:\/\/www.ti.com\/lit\/ds\/symlink\/lm1117.pdf","price":"$0.48 @ 1ku","product_introduction":"The LM1117MPX-1.8 from Texas Instruments is an 800mA low-dropout positive voltage regulator with a fixed 1.8V output in an SOT-223 surface-mount package. The MP suffix denotes the SOT-223 package, X indicates tape and reel packaging, and 1.8 specifies the output voltage. The LM1117 is the industry-standard 800mA LDO regulator, second-sourced by multiple manufacturers. The 1.2V typical dropout voltage at 800mA allows operation from a 3.3V input with 300mV of headroom. The +\/-1% output voltage accuracy is achieved through zener-trimmed bandgap reference technology, making the device suitable for applications with tight voltage tolerances such as FPGA I\/O banks. The internal current limiting protects against output overload, while the thermal shutdown prevents damage from excessive junction temperature. A minimum 10uF tantalum output capacitor is required for stability and improved transient response. The SOT-223 package provides a compact footprint with reasonable thermal performance (Rth JA approximately 80C\/W on standard PCB) for the 800mA current rating.","working_principle":"The LM1117MPX-1.8 uses a PNP pass transistor-based LDO topology. The input voltage feeds the emitter of the PNP pass transistor, whose collector provides the regulated 1.8V output. An error amplifier compares a fraction of the output voltage (via the internal resistor divider for the fixed 1.8V version) with an internal bandgap reference voltage. The error amplifier drives the base of the PNP pass transistor to maintain regulation. The PNP structure allows the dropout voltage to be only VCE(sat) of the pass transistor, typically 1.2V at 800mA, much lower than NPN-based regulators that require at least VBE + VCE(sat) dropout. The zener-trimmed bandgap reference uses laser-trimmed resistors to achieve the +\/-1% output voltage tolerance. The current limiting circuit monitors the output current by sensing the voltage across an internal resistor in series with the pass transistor. When the current exceeds approximately 1.5A, the base drive to the pass transistor is reduced. The thermal shutdown circuit monitors the junction temperature and turns off the pass transistor when it exceeds approximately 165C, with approximately 30C of hysteresis to prevent oscillation. The output capacitor (10uF minimum tantalum) provides the dominant pole for loop stability and improves transient response. Ceramic capacitors can be used but may require a series resistor (ESR) for stability due to the very low ESR creating a zero at too high a frequency.","pin_description":"
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