Datasheet LT3505 (Analog Devices) - 5
| Manufacturer | Analog Devices |
| Description | 1.2A, Step-Down Switching Regulator in 3mm × 3mm DFN |
| Pages / Page | 24 / 5 — Undervoltage Lockout. Switching Frequency. Frequency Foldback, RT = … |
| File Format / Size | PDF / 832 Kb |
| Document Language | English |
Undervoltage Lockout. Switching Frequency. Frequency Foldback, RT = 75.0k. Typical Minimum Input Voltage,. Soft-Start
Model Line for this Datasheet
Text Version of Document
LT3505 TYPICAL PERFORMANCE CHARACTERISTICS
Undervoltage Lockout Switching Frequency Frequency Foldback, RT = 75.0k
4.00 2.40 0.6 TA = 25°C 3.90 2.20 RT = 21k 0.5 3.80 2.00 3.70 1.80 0.4 3.60 1.60 RT = 30.1k 3.50 0.3 UVLO (V) 1.40 3.40 1.20 0.2 3.30 PIN BIAS VOLTAGE (V) R T 3.20 1.00 SWITCHING FREQUENCY (MHz) 0.1 R 3.10 0.80 T = 75.0k 3.00 0.60 0 –50 –25 0 25 50 75 100 125 –50 –25 0 25 50 75 100 125 0 0.1 0.2 0.3 0.4 0.5 0.6 0.7 0.8 TEMPERATURE (°C) TEMPERATURE (°C) FB VOLTAGE (V) 3505 G10 3505 G12
Typical Minimum Input Voltage, Soft-Start SHDN Pin Current (VOUT = 5V, fSW = 750kHz)
2.0 50 7.2 TA = 25°C TA = 25°C TA = 25°C 1.8 45 7.0 TO START 1.6 40 6.8 1.4 35 6.6 1.2 6.4 1.0 (µA) 30 25 6.2 0.8 I SHDN 20 6.0 0.6 15 INPUT VOLTAGE (V) 5.8 TO RUN SWITCH CURRENT LIMIT (A) 0.4 10 5.6 0.2 5 5.4 0 0 5.2 0 0.25 0.50 0.75 1 1.25 1.50 1.75 2 0 2 4 6 8 10 12 14 16 18 20 1 10 100 1000 SHDN PIN VOLTAGE (V) VSHDN (V) LOAD CURRENT (mA) 3505 G14 3505 G15
Typical Minimum Input Voltage, Typical Minimum Input Voltage, Typical Minimum Input Voltage, (VOUT = 3.3V, fSW = 750kHz) (VOUT = 3.3V, fSW = 2.2MHz) (VOUT = 5V, fSW = 2.2MHz)
5.5 7.0 TA = 25°C TA = 25°C 5.3 5.5 6.8 TO START 5.1 TO START TO START 6.6 4.9 5.0 6.4 TO RUN 4.7 6.2 4.5 6.0 4.5 4.3 TO RUN 5.8 INPUT VOLTAGE (V) 4.1 TO RUN INPUT VOLTAGE (V) INPUT VOLTAGE (V) 5.6 3.9 4.0 5.4 3.7 5.2 TA = 25°C 3.5 3.5 5.0 1 10 100 1000 1 10 100 1000 1 10 100 1000 LOAD CURRENT (mA) LOAD CURRENT (mA) LOAD CURRENT (mA) 3505fc 5
Undervoltage Lockout Switching Frequency Frequency Foldback, RT = 75.0k
4.00 2.40 0.6 TA = 25°C 3.90 2.20 RT = 21k 0.5 3.80 2.00 3.70 1.80 0.4 3.60 1.60 RT = 30.1k 3.50 0.3 UVLO (V) 1.40 3.40 1.20 0.2 3.30 PIN BIAS VOLTAGE (V) R T 3.20 1.00 SWITCHING FREQUENCY (MHz) 0.1 R 3.10 0.80 T = 75.0k 3.00 0.60 0 –50 –25 0 25 50 75 100 125 –50 –25 0 25 50 75 100 125 0 0.1 0.2 0.3 0.4 0.5 0.6 0.7 0.8 TEMPERATURE (°C) TEMPERATURE (°C) FB VOLTAGE (V) 3505 G10 3505 G12
Typical Minimum Input Voltage, Soft-Start SHDN Pin Current (VOUT = 5V, fSW = 750kHz)
2.0 50 7.2 TA = 25°C TA = 25°C TA = 25°C 1.8 45 7.0 TO START 1.6 40 6.8 1.4 35 6.6 1.2 6.4 1.0 (µA) 30 25 6.2 0.8 I SHDN 20 6.0 0.6 15 INPUT VOLTAGE (V) 5.8 TO RUN SWITCH CURRENT LIMIT (A) 0.4 10 5.6 0.2 5 5.4 0 0 5.2 0 0.25 0.50 0.75 1 1.25 1.50 1.75 2 0 2 4 6 8 10 12 14 16 18 20 1 10 100 1000 SHDN PIN VOLTAGE (V) VSHDN (V) LOAD CURRENT (mA) 3505 G14 3505 G15
Typical Minimum Input Voltage, Typical Minimum Input Voltage, Typical Minimum Input Voltage, (VOUT = 3.3V, fSW = 750kHz) (VOUT = 3.3V, fSW = 2.2MHz) (VOUT = 5V, fSW = 2.2MHz)
5.5 7.0 TA = 25°C TA = 25°C 5.3 5.5 6.8 TO START 5.1 TO START TO START 6.6 4.9 5.0 6.4 TO RUN 4.7 6.2 4.5 6.0 4.5 4.3 TO RUN 5.8 INPUT VOLTAGE (V) 4.1 TO RUN INPUT VOLTAGE (V) INPUT VOLTAGE (V) 5.6 3.9 4.0 5.4 3.7 5.2 TA = 25°C 3.5 3.5 5.0 1 10 100 1000 1 10 100 1000 1 10 100 1000 LOAD CURRENT (mA) LOAD CURRENT (mA) LOAD CURRENT (mA) 3505fc 5
