LTC3417A-1 TYPICAL PERFORMANCE CHARACTERISTICSRDS(ON) vs VIN OUT2Frequency vs VINFrequency vs Temperature 0.20 6 15 TA = 27°C 4 0.19 10 FREQ = VIN P-CHANNEL SWITCH 2 FREQ = 143k TO GROUND 0.18 5 0 (Ω) 0.17 –2 0 DS(ON) FREQ = 143k TO GROUND R –4 0.16 FREQ = V –5 IN –6 FREQUENCY VARIATION (%) FREQUENCY VARIATION (%) 0.15 –10 N-CHANNEL SWITCH –8 0.14 –10 –15 2 2.5 3 3.5 4 4.5 5 5.5 2 2.5 3 3.5 4 4.5 5 5.5 –50 –25 0 25 50 75 100 125 VIN (V) VIN (V) TEMPERATURE (°C) 3417A-1 G16 3417A-1 G17 3417A-1 G18 PIN FUNCTIONS (DFN/TSSOP)RUN1 (Pin 1/Pin 2): Enable for 1.5A Regulator. When SYNC/MODE (Pin 9/Pin 12): Combination Mode Selection at Logic 1, 1.5A regulator is running. When at 0V, 1.5A and Oscillator Synchronization Pin. This pin controls the op- regulator is off. When both RUN1 and RUN2 are at 0V, the eration of the device. When the voltage on the SYNC/MODE part is in shutdown. pin is >(VIN – 0.5V), Burst Mode operation is selected. When the voltage on the SYNC/MODE pin is <0.5V, pulse VIN1 (Pin 2/Pin 3): Supply Pin for P-Channel Switch of skipping mode is selected. When the SYNC/MODE pin is 1.5A Regulator. held at VIN/2, forced continuous mode is selected. The ITH1 (Pin 3/Pin 4): Error Amplifi er Compensation Point oscillation frequency can be synchronized to an external for 1.5A Regulator. The current comparator threshold oscillator applied to this pin. When synchronized to an increases with this control voltage. Nominal voltage range external clock, pulse skip mode is selected. for this pin is 0V to 1.5V. SW2 (Pin 10/Pin 13): Switch Node Connection to the VFB1 (Pin 4/Pin 5): Receives the feedback voltage from Inductor for the 1A Regulator. This pin swings from VIN2 external resistive divider across the 1.5A regulator output. to PGND2. Nominal voltage for this pin is 0.8V. POR (Pin 11/Pin 14): The Power-On-Reset Pin. This VFB2 (Pin 5/Pin 6): Receives the feedback voltage from open drain-logic output is pulled to GND when the output external resistive divider across the 1A regulator output. voltage of either regulator falls 8% below regulation and Nominal voltage for this pin is 0.8V. goes high approximately 150ms after both regulators are I above –6% of regulation. If either RUN1 or RUN2 is low TH2 (Pin 6/Pin 7): Error Amplifi er Compensation Point for 1A regulator. The current comparator threshold increases (the respective regulator is in sleep mode and therefore with this control voltage. Nominal voltage range for this the output voltage is low), then POR refl ects the regulation pin is 0V to 1.5V. of the running regulator. RUN2 (Pin 7/Pin 8): Enable for 1A Regulator. When at FREQ (Pin 12/Pin 15): Frequency Set Pin. When FREQ is Logic 1, 1A regulator is running. When at 0V, 1A regula- at VIN, internal oscillator runs at 1.5MHz. When a resistor tor is off. When both RUN1 and RUN2 are at 0V, the part is connected from this pin to ground, the internal oscillator is in shutdown. frequency can be varied from 0.6MHz to 4MHz. VGNDA (Pin 13/Pin 16): Analog Ground Pin for Internal IN2 (Pin 8/Pin 9): Supply Pin for P-Channel Switch of 1A Regulator and Supply for Analog Circuitry. Analog Circuitry. 3417a1fa 6