LT1959 WWWUABSOLUTE MAXIMUM RATINGS (Note 1) Input Voltage .. 16V SYNC Pin Voltage ... 7V BOOST Voltage .. 30V Operating Junction Temperature Range BOOST Pin Above Input Voltage ... 15V LT1959C .. 0°C to 125°C SHDN Pin Voltage ... 7V LT1959I ... – 40°C to 125°C FB Pin Voltage ... 3.5V Storage Temperature Range .. – 65°C to 150°C FB Pin Current ... 1mA Lead Temperature (Soldering, 10 sec)... 300°C UWUPACKAGE/ORDER INFORMATION FRONT VIEW ORDER PART ORDER PART 7 FB NUMBER TOP VIEW NUMBER 6 BOOST V 1 8 IN VSW 5 V TAB IN 4 GND LT1959CR IS LT1959CS8 BOOST 2 7 SYNC 3 V GND SW LT1959IR LT1959IS8 2 SHDN FB 3 6 SHDN 1 VC GND** 4 5 VC R PACKAGE 7-LEAD PLASTIC DD S8 PACKAGE 8-LEAD PLASTIC SO TJMAX = 150°C, θJA = 30°C/W S8 PART MARKING WITH PACKAGE SOLDERED TO 0.5 SQUARE INCH TJMAX = 150°C, θJA = 80°C/W COPPER AREA OVER BACKSIDE GROUND PLANE OR **WITH (FUSED GND) GROUND PIN INTERNAL POWER PLANE. θ 1959 JA CAN VARY FROM 20°C/W CONNECTED TO GROUND PLANE OR TO > 40°C/W DEPENDING ON MOUNTING TECHNIQUES LARGE LANDS 1959I ELECTRICAL CHARACTERISTICS The ● denotes the specifications which apply over the full operating temperature range, otherwise specifications are at TA = 25 ° C, TJ = 25 ° C, VIN = 5V, VC = 1.5V, Boost = VIN + 5V, switch open, unless otherwise noted.PARAMETERCONDITIONSMINTYPMAXUNITS Feedback Voltage (Adjustable) All Conditions ● 1.19 1.21 1.23 V Reference Voltage Line Regulation 4.3V ≤ VIN ≤ 15V 0.01 0.03 %/ V Feedback Input Bias Current ● –0.5 0 0.5 µA Error Amplifier Voltage Gain (Note 2) 200 400 Error Amplifier Transconductance ∆I (VC) = ±10µA 1500 2000 2700 µMho ● 1000 3100 µMho VC Pin to Switch Current Transconductance 5.3 A/ V Error Amplifier Source Current VFB = 1.05V ● 140 225 320 µA Error Amplifier Sink Current VFB = 1.35V ● 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 = 1.05V, DC ≤ 50% ● 4.5 6 8.5 A Slope Compensation DC = 80% 0.8 A 2