Electronic Components Datasheet Search |
|
LT1578 Datasheet(PDF) 3 Page - Linear Technology |
|
LT1578 Datasheet(HTML) 3 Page - Linear Technology |
3 / 28 page 3 LT1578/LT1578-2.5 PARAMETER CONDITIONS MIN TYP MAX UNITS Boost Current (Note 5) ISW = 0.5A q 918 mA ISW = 1.5A q 27 50 mA VIN Supply Current (Note 6) q 1.9 2.7 mA Shutdown Supply Current VSHDN = 0V, VIN ≤ 15V, VSW = 0V, VC Open 20 50 µA q 75 µA Lockout Threshold VC Open q 2.34 2.42 2.50 V Shutdown Thresholds VC Open Device Shutting Down q 0.13 0.37 0.60 V Device Starting Up q 0.25 0.45 0.7 V Synchronization Threshold 1.5 2.2 V Synchronizing Range 250 400 kHz SYNC Pin Input Resistance 40 k Ω Note 1: Absolute Maximum Ratings are those values beyond which the life of a device may be impaired. Note 2: Gain is measured with a VC swing equal to 200mV above the switching threshold level to 200mV below the upper clamp level. Note 3: Minimum input voltage is not measured directly, but is guaranteed by other tests. It is defined as the voltage where internal bias lines are still regulated so that the reference voltage and oscillator frequency remain constant. Actual minimum input voltage to maintain a regulated output will depend on output voltage and load current. See Applications Information. Note 4: This is the minimum voltage across the boost capacitor needed to guarantee full saturation of the internal power switch. Note 5: Boost current is the current flowing into the boost pin with the pin held 5V above input voltage. It flows only during switch on time. Note 6: Input supply current is the bias current drawn by the input pin with switching disabled. Note 7: Switch on resistance is calculated by dividing VIN to VSW voltage by the forced current (1.5A). See Typical Performance Characteristics for the graph of switch voltage at other currents. Note 8: Slope compensation is the current subtracted from the switch current limit at 80% duty cycle. See Maximum Output Load Current in the Applications Information section for further details. Note 9: Minimum on-time is 400ns typical. For a 200kHz operating frequency this means the minimum duty cycle is 8%. In frequency foldback mode, the effective duty cycle will be less than 8%. Note 10: Transconductance and voltage gain refer to the internal amplifier exclusive of the voltage divider. To calculate gain and transconductance referred to the sense pin on the fixed voltage parts, divide values shown by the ratio 2.5/1.21. TYPICAL PERFORMANCE CHARACTERISTICS Switch Voltage Drop JUNCTION TEMPERATURE ( °C) –50 1.23 1.22 1.21 1.20 1.19 100 1576 G03 –25 0 25 50 75 125 SWITCH CURRENT (A) 0 0.5 0.4 0.3 0.2 0.1 0 0.25 0.50 0.75 1.00 1576 G01 1.25 1.50 125 °C –20 °C 25 °C Feedback Pin Voltage Switch Peak Current Limit DUTY CYCLE (%) 0 2.5 2.0 1.5 1.0 0.5 0 80 1576 G02 20 40 60 100 TYPICAL MINIMUM The q denotes specifications which apply over the full operating tempera- ture range, otherwise specifications are at TJ = 25°C. VIN = 5V, VC = 1.5V, Boost = VIN + 5V, switch open, unless otherwise noted. ELECTRICAL CHARACTERISTICS |
Similar Part No. - LT1578_15 |
|
Similar Description - LT1578_15 |
|
|
Link URL |
Privacy Policy |
ALLDATASHEET.COM |
Does ALLDATASHEET help your business so far? [ DONATE ] |
About Alldatasheet | Advertisement | Datasheet Upload | 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 |