 |
Electronic Components Datasheet Search |
|
|
Electronic Components Datasheet Search |
|
LT1761 Datasheet(PDF) 9 Page - Linear Technology |
|
||||||||||||||||||||||||||||||
LT1761 Datasheet(HTML) 9 Page - Linear Technology |
|
|
9 / 16 page  9 LT3020/LT3020-1.2/ LT3020-1.5/LT3020-1.8 3020fc APPLICATIO S I FOR ATIO The LT3020 is a very low dropout linear regulator capable of 0.9V input supply operation. Devices supply 100mA of output current and dropout voltage is typically 150mV. Quiescent current is typically 120 µA and drops to 3µA in shutdown. The LT3020 incorporates several protection features, making it ideal for use in battery-powered sys- tems. The device protects itself against reverse-input and reverse-output voltages. In battery backup applications where the output is held up by a backup battery when the input is pulled to ground, the LT3020 acts as if a diode is in series with its output which prevents reverse current flow. In dual supply applications where the regulator load is returned to a negative supply, the output can be pulled below ground by as much as 10V without affecting start- up or normal operation. Adjustable Operation The LT3020’s output voltage range is 0.2V to 9.5V. Figure 1 shows that the output voltage is set by the ratio of two external resistors. The device regulates the output to maintain the ADJ pin voltage at 200mV referenced to ground. The current in R1 equals 200mV/R1 and the current in R2 is the current in R1 minus the ADJ pin bias current. The ADJ pin bias current of 20nA flows out of the pin. Use the formula in Figure 1 to calculate output voltage. An R1 value of 20k sets the resistor divider current to 10 µA. Note that in shutdown the output is turned off and the divider current is zero. Curves of ADJ Pin Voltage vs Temperature and ADJ Pin Bias Current vs Temperature appear in the Typical Performance Characteristics section. Specifications for output voltages greater than 200mV are proportional to the ratio of desired output voltage to 200mV; (VOUT/200mV). For example, load regulation for BLOCK DIAGRA SHUTDOWN – + CURRENT GAIN THERMAL SHUTDOWN R3 R2 R1 3020 BD D1 Q1 D2 Q2 ERROR AMP NO-LOAD RECOVERY Q3 IN (7, 8) OUT (1, 2) OUT SENSE (3) NOTE: FOR LT3020 ADJUST PIN 3 IS CONNECTED TO THE ADJUST PIN, R1 AND R2 ARE EXTERNAL. FOR LT3020-1.X PIN 3 IS CONNECTED TO THE OUTPUT SENSE PIN, R1 AND R2 ARE INTERNAL. GND (4,9) ADJ (3) 25k SHDN (5) 200mV 212mV BIAS CURRENT AND REFERENCE GENERATOR FIXED VOUT 1.2V 1.5V 1.8V R1 20k 20k 20k R2 100k 130k 160k IN SHDN R2 R1 3020 F01 OUT VIN ADJ GND LT3020-ADJ VOUT + R2 R1 VOUT = 200mV VADJ = 200mV IADJ = 20nA AT 25°C OUTPUT RANGE = 0.2V TO 9.5V 1 + – IADJ (R2) () Figure 1. Adjustable Operation |
Similar Part No. - LT1761 |
|
Similar Description - LT1761 |
|
|
|
Link URL |
| Privacy Policy |
| ALLDATASHEET.NET |
| Does ALLDATASHEET help your business so far? [ DONATE ] |
About Alldatasheet | Advertisement | Contact us | Privacy Policy | Link Exchange | Manufacturer List All Rights Reserved©Alldatasheet.com |
| Russian : Alldatasheetru.com | Korean : Alldatasheet.co.kr | Spanish : Alldatasheet.es | French : Alldatasheet.fr | Italian : Alldatasheetit.com Portuguese : Alldatasheetpt.com | Polish : Alldatasheet.pl | Vietnamese : Alldatasheet.vn Indian : Alldatasheet.in | Mexican : Alldatasheet.com.mx | British : Alldatasheet.co.uk | New Zealand : Alldatasheet.co.nz |
|
Family Site : ic2ic.com |
icmetro.com |
English ▼
English
Chinese
German
Japanese
Russian
Korean
Spanish
French
Italian
Portuguese
Polish
Vietnamese
Indian
Mexican
British
New Zealand
