 |
Electronic Components Datasheet Search |
|
|
Electronic Components Datasheet Search |
|
LT1302CN8 Datasheet(PDF) 8 Page - Linear Technology |
|
||||||||||||||||||||||||||||||
LT1302CN8 Datasheet(HTML) 8 Page - Linear Technology |
|
|
8 / 16 page  8 LT1302/LT1302-5 APPLICATIONS INFORMATION and there is no low frequency component. The total ESR is under 0.03 Ω. If a single 100µF aluminum electrolytic capacitor is used instead, the converter mode-hops be- tween current mode and Burst Mode due to high ESR, causing the voltage comparator to trip as shown in Figure 5. The ripple voltage is now over 500mVP-P and contains a low frequency component. Maximum allowable output capacitor ESR can be calculated by the following formula: ESR VV VA MAX OS OUT REF = × × 1 where, VOS = 15mV VREF = 1.24V 500 µs/DIV 1302 F04 VOUT 50mV/DIV AC COUPLED ILOAD Figure 4. Low ESR Output Capacitor Results in Stable Operation. Ripple Voltage is Under 30mVP-P 500 µs/DIV 1302 F05 VOUT 200mV/DIV AC COUPLED ILOAD Figure 5. Inexpensive Electrolytic Capacitor Has High ESR, Resulting in Mode-Hop, Ripple Voltage Amplitude Is Over 500mVP-P and Includes Low Frequency Component 510mA 10mA 510mA 10mA Input Capacitor The input supply should be decoupled with a good quality electrolytic capacitor close to the LT1302 to provide a stable input supply. Long leads or traces from power source to the switcher can have considerable impedance at the LT1302’s switching frequency. The input capacitor provides a low impedance at high frequency. A 0.1 µF ceramic capacitor is required right at the VIN pin. When the input voltage can be above 5V, a 10 Ω/1µF decoupling network for VIN is recommended as detailed in Figure 6. This network is also recommended when driving a trans- former. Figure 6. A 10 Ω/1µF Decoupling Network at VIN Is Recommended When Input Voltage Is Above 5V + + VIN SW PGND 1 µF LT1302 • • • GND 47 µF TO 100 µF 10 Ω 1302 F06 VIN > 5V Table 2 lists capacitor vendors along with device types. Table 2. Recommended Capacitors VENDOR SERIES TYPE PHONE NO. AVX TPS Surface Mount (803) 448-9411 Sanyo OS-CON Through Hole (619) 661-6835 Sprague 595D Surface Mount (603) 224-1961 Diode Selection A 2A Schottky diode such as Motorola MBRS130LT3 has been found to be the best available. Other choices include 1N5821 or MBRS130T3. Do not use “general purpose” diodes such as 1N4001. They are much too slow for use in switching regulator applications. |
Similar Part No. - LT1302CN8 |
|
Similar Description - LT1302CN8 |
|
|
|
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
