LT1374 ELECTRICAL CHARACTERISTICS The ● denotes specifications which apply over the full operating tempera-ture range, otherwise specifications are at TJ = 25 ° C. VIN = 15V, VC = 1.5V, Boost = VIN + 5V, switch open, unless otherwise noted. PARAMETERCONDITIONSMINTYPMAXUNITS Feedback Voltage (Adjustable) 2.39 2.42 2.45 V All Conditions ● 2.36 2.48 V Sense Voltage (Fixed 5V) 4.94 5.0 5.06 V All Conditions ● 4.90 5.10 V SENSE Pin Resistance 7 10 14 kΩ Reference Voltage Line Regulation 5V ≤ VIN ≤ 25V (5V ≤ VIN ≤ 32V for LT1374HV) 0.01 0.03 %/V Feedback Input Bias Current ● 0.5 2 µA Error Amplifier Voltage Gain (Notes 2, 8) 200 400 Error Amplifier Transconductance ∆I (VC) = ±10µA (Note 8) 1500 2000 2700 µMho ● 1000 3100 µMho VC Pin to Switch Current Transconductance 5.3 A/ V Error Amplifier Source Current VFB = 2.1V or VSENSE = 4.4V ● 140 225 320 µA Error Amplifier Sink Current VFB = 2.7V or VSENSE = 5.6V ● 140 225 320 µA VC Pin Switching Threshold Duty Cycle = 0 0.9 V VC Pin High Clamp 2.1 V Switch Current Limit VC Open, VFB = 2.1V or VSENSE = 4.4V, DC ≤ 50% ● 4.5 6 8.5 A Slope Compensation (Note 9) DC = 80% 0.8 A Switch On Resistance (Note 7) ISW = 4.5A 0.07 0.1 Ω ● 0.13 Ω Maximum Switch Duty Cycle VFB = 2.1V or VSENSE = 4.4V 90 93 % ● 86 93 % Switch Frequency VC Set to Give 50% Duty Cycle 460 500 540 kHz ● 440 560 kHz Switch Frequency Line Regulation 5V ≤ VIN ≤ 25V, (5V ≤ VIN ≤ 32V for LT1374HV) ● 0 0.15 %/ V Frequency Shifting Threshold on FB Pin ∆f = 10kHz ● 0.8 1.0 1.3 V Minimum Input Voltage (Note 3) ● 5.0 5.5 V Minimum Boost Voltage (Note 4) ISW ≤ 4.5A ● 2.3 3.0 V Boost Current (Note 5) ISW = 1A ● 20 35 mA ISW = 4.5A ● 90 140 mA VIN Supply Current (Note 6) VBIAS = 5V ● 0.9 1.4 mA BIAS Supply Current (Note 6) VBIAS = 5V ● 3.2 4.0 mA Shutdown Supply Current VSHDN = 0V, VIN ≤ 25V, VSW = 0V, VC Open 20 50 µA ● 75 µA VSHDN = 0V, VIN ≤ 32V, VSW = 0V, VC Open 30 75 µA ● 100 µA Lockout Threshold VC Open ● 2.3 2.38 2.46 V Shutdown Thresholds VC Open Device Shutting Down ● 0.13 0.37 0.60 V Device Starting Up ● 0.25 0.45 0.7 V Synchronization Threshold ● 1.5 2.2 V Synchronizing Range 580 1000 kHz SYNC Pin Input Resistance 40 kΩ Note 1: Absolute Maximum Ratings are those values beyond which the life regulated so that the reference voltage and oscillator frequency remain of a device may be impaired. constant. Actual minimum input voltage to maintain a regulated output will Note 2: Gain is measured with a V depend on output voltage and load current. See Applications Information. C swing equal to 200mV above the switching threshold level to 200mV below the upper clamp level. Note 4: This is the minimum voltage across the boost capacitor needed to Note 3: Minimum input voltage is not measured directly, but is guaranteed guarantee full saturation of the internal power switch. by other tests. It is defined as the voltage where internal bias lines are still 1374fd 3