{"product_id":"lm7905-negative-voltage-regulator","title":"LM7905 negative voltage regulator in Pakistan","description":"\u003ch3 id=\"description\" class=\"tab-list-title\"\u003e\u003cspan style=\"font-size: 20px;\"\u003eDescription\u003c\/span\u003e\u003c\/h3\u003e\n\u003cp\u003e\u003cspan style=\"font-size: 20px;\"\u003eThe image of LM7905 negative voltage regulator is:\u003c\/span\u003e\u003c\/p\u003e\n\u003cdiv id=\"content_description\" class=\"ty-wysiwyg-content content-description\"\u003e\n\u003cdiv\u003e\n\u003cdiv class=\"electro-description\"\u003e\n\u003cp\u003e\u003cspan style=\"font-size: 20px;\"\u003e\u003cimg src=\"https:\/\/cdn.shopify.com\/s\/files\/1\/0965\/3623\/2249\/files\/7805-pinout_569d5b0f-6bc3-4020-b861-119a9b119dae.jpg?v=1789233448\" alt=\"Image result for voltage regulator 7812 pinout\" width=\"275\" height=\"195\" loading=\"lazy\"\u003e\u003c\/span\u003e\u003c\/p\u003e\n\u003cp\u003e\u003cspan style=\"font-size: 20px;\"\u003eWe all very well know regarding the building procedures a DC power supply circuit using a transformer, a bridge rectifier and a filter capacitor.\u003c\/span\u003e\u003c\/p\u003e\n\u003cp\u003e\u003cspan style=\"font-size: 20px;\"\u003eIt just requires connecting four diodes in a bridge configuration and connect it to the secondary of the transformer, the capacitor goes to the output of the bridge terminals.\u003c\/span\u003e\u003cbr\u003e\n\u003cspan style=\"font-size: 20px;\"\u003eThe output produced across the capacitor is approximately equal to the rated voltage of the transformer, rather a few volts higher than the transformer spec.\u003c\/span\u003e\u003cbr\u003e\n\u003cspan style=\"font-size: 20px;\"\u003eHowever the voltage obtained from the above simple configuration is never regulated and stabilized, meaning the output from it will never be constant and will vary with the varying input mains voltage levels, which we know is never constant.\u003c\/span\u003e\u003c\/p\u003e\n\u003ch4\u003e\u003cspan style=\"font-size: 20px;\"\u003eVarying Voltage\u003c\/span\u003e\u003c\/h4\u003e\n\u003cp\u003e\u003cspan style=\"font-size: 20px;\"\u003eA varying voltage can cause drastic consequences to a sensitive electronic circuit, for example a TTL, LS and HC series of ICs cannot tolerate more than 5 volts and can get immediately damaged.\u003c\/span\u003e\u003cbr\u003e\n\u003cspan style=\"font-size: 20px;\"\u003eA CMOS IC cannot stand more than 16 to 18 volts.\u003c\/span\u003e\u003cbr\u003e\n\u003cspan style=\"font-size: 20px;\"\u003eA relay if operated at voltages more than its rating can become hot and waste electricity unnecessarily.\u003c\/span\u003e\u003c\/p\u003e\n\u003ch2\u003e\u003cspan style=\"font-size: 20px;\"\u003eOther issues\u003c\/span\u003e\u003c\/h2\u003e\n\u003cp\u003e\u003cspan style=\"font-size: 20px;\"\u003eThere are several other issues which might be faced with electronic circuits if the applied is an unregulated one.\u003c\/span\u003e\u003cbr\u003e\n\u003cspan style=\"font-size: 20px;\"\u003eFor solving the above issue, many high grade yet very simple to configure chips have been designed and are available cheaply and plentifully in our electronic markets.\u003c\/span\u003e\u003cbr\u003e\n\u003cspan style=\"font-size: 20px;\"\u003eThe 78XX voltage regulator series for example, comes with most of the standard voltage ratings which can use in conjunction with an ordinary power supply DC for obtaining high grade, clean voltage controlled outputs.\u003c\/span\u003e\u003c\/p\u003e\n\u003ch2\u003e\u003cspan style=\"font-size: 20px;\"\u003eSpecifications\u003c\/span\u003e\u003c\/h2\u003e\n\u003cp\u003e\u003cspan style=\"font-size: 20px;\"\u003eThe specifications of the 78XX series IC are understandable  with the following points:\u003c\/span\u003e\u003c\/p\u003e\n\u003cp\u003e\u003cspan style=\"font-size: 20px;\"\u003eOutput voltage tolerances are around 2% at Tj\u003c\/span\u003e\u003cbr\u003e\n\u003cspan style=\"font-size: 20px;\"\u003e= 25 C and 4%\u003c\/span\u003e\u003cbr\u003e\n\u003cspan style=\"font-size: 20px;\"\u003eLine regulation is around 0.01% of VOUT\/V of VIN at 1A load\u003c\/span\u003e\u003cbr\u003e\n\u003cspan style=\"font-size: 20px;\"\u003eInternal circuitry is thermal and overload protected\u003c\/span\u003e\u003cbr\u003e\n\u003cspan style=\"font-size: 20px;\"\u003eInternal short-circuit current limit protections are also include.\u003c\/span\u003e\u003cbr\u003e\n\u003cspan style=\"font-size: 20px;\"\u003eOutput transistor safe area protection is also one of the features of these ICs\u003c\/span\u003e\u003c\/p\u003e\n\u003cp\u003e\u003cspan style=\"font-size: 20px;\"\u003eThe entire range of these ICs are  in the following table:\u003c\/span\u003e\u003c\/p\u003e\n\u003cdiv class=\"separator\"\u003e\u003cspan style=\"font-size: 20px;\"\u003e\u003ca href=\"https:\/\/cdn.shopify.com\/s\/files\/1\/0965\/3623\/2249\/files\/78XX_voltage_regulator_range_of_ICs_18fec358-110f-493d-abcb-63ba4a2525db.jpg?v=1789233452\"\u003e\u003cimg src=\"https:\/\/cdn.shopify.com\/s\/files\/1\/0965\/3623\/2249\/files\/78XX_voltage_regulator_range_of_ICs_84e93f59-d4d7-4e33-87f8-b9bb3fc32b2d.jpg?v=1789233450\" alt=\"\" width=\"320\" height=\"319\" border=\"0\" loading=\"lazy\"\u003e\u003c\/a\u003e\u003c\/span\u003e\u003c\/div\u003e\n\u003cp\u003e\u003cspan style=\"font-size: 20px;\"\u003eHow a 7805\/7812\/7815\/7824 ICs are use or connect in electronic circuits.\u003c\/span\u003e\u003c\/p\u003e\n\u003cp\u003e\u003cspan style=\"font-size: 20px;\"\u003eA classic example is  \u003ca href=\"http:\/\/homemadecircuitsandschematics.blogspot.in\/2012\/03\/how-to-make-simple-dc-to-dc-cell-phone.html\" target=\"_blank\" rel=\"noopener noreferrer\"\u003ein this article\u003c\/a\u003e where a 7805 IC is used as a cell phone charger regulator.\u003c\/span\u003e\u003c\/p\u003e\n\u003ch2\u003e\u003cspan style=\"font-size: 20px;\"\u003eRefer circuit diagram\u003c\/span\u003e\u003c\/h2\u003e\n\u003cul\u003e\n\u003cli\u003e\u003cspan style=\"font-size: 20px;\"\u003eThese ICs have just three leads, making it very easy to understand and connect. The leads are assigned as input, ground and output respectively.\u003c\/span\u003e\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003cul\u003e\n\u003cli\u003e\u003cspan style=\"font-size: 20px;\"\u003eKeeping the printed side toward you, the left side lead is the input. The center one is the ground and the right side lead is the output.\u003c\/span\u003e\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003cul\u003e\n\u003cli\u003e\u003cspan style=\"font-size: 20px;\"\u003eThe DC from any standard power supply is apply across the input and the ground leads of the IC. The positive goes to the input while the negative is connect to the ground.\u003c\/span\u003e\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003cdiv\u003e\u003c\/div\u003e\n\u003cul\u003e\n\u003cli\u003e\u003cspan style=\"font-size: 20px;\"\u003eThe output is acquire across the output and the ground pins of the IC. The positive receives from the “output” pin and the negative from the common ground line.\u003c\/span\u003e\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003cp\u003e\u003cspan style=\"font-size: 20px;\"\u003eMany example application circuits and connection details can be found in this \u003ca href=\"https:\/\/cdn.shopify.com\/s\/files\/1\/0965\/3623\/2249\/files\/lm340-n_400a4df6-3b2b-4a84-943a-50f28d8ae6e7.pdf?v=1789233453\" target=\"_blank\" rel=\"noopener noreferrer\"\u003eARTICLE\u003c\/a\u003e\u003c\/span\u003e\u003c\/p\u003e\n\u003c\/div\u003e\n\u003c\/div\u003e\n\u003c\/div\u003e","brand":"Electronics Hub","offers":[{"title":"Default Title","offer_id":54466802188601,"sku":"product-6251","price":25.0,"currency_code":"PKR","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0965\/3623\/2249\/files\/LM7905-Voltage-Regulator-1.jpg?v=1789233458","url":"https:\/\/electronicshub.pk\/products\/lm7905-negative-voltage-regulator","provider":"Electronics Hub","version":"1.0","type":"link"}