SC1403ITSTRT Semtech, SC1403ITSTRT Datasheet
SC1403ITSTRT
Specifications of SC1403ITSTRT
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SC1403ITSTRT Summary of contents
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... SC1403 provides synchronous buck converter control for two (3.3V and 5V) power supplies. An efficiency of 95% can be achieved for the two supplies. The SC1403 uses Semtech’s proprietary Virtual Current Sense nology along with external error amplifier compensation to achieve enhanced stability and DC accuracy over a wide range of output filter components while maintain- ing fixed frequency operation ...
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... Exceeding the specifications below may result in permanent damage to the device, or device malfunction. Operation outside of the parameters specified in the Electrical Characteristics section is not implied Electrical Characteristics Unless otherwise noted 15V, both PWMs on, SYNC = 0V, VL load = 0mA, REF load = 0mA, PSAVE +25°C. Circuit = Typical Application Circuit 2004 Semtech Corp < < SC1403 PRELIMINARY ± ...
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... POWER MANAGEMENT Electrical Characteristics (Cont.) Unless otherwise noted 15V, both PWMs on, SYNC = 0V, VL load = 0mA, REF load = 0mA, PSAVE +25°C. Circuit = Typical Application Circuit 2004 Semtech Corp < < < I < µ A < I < µ < I < SC1403 =-40 to 85°C. Typical values are at ...
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... POWER MANAGEMENT Electrical Characteristics (Cont.) Unless otherwise noted 15V, both PWMs on, SYNC = 0V, VL load = 0mA, REF load = 0mA, PSAVE +25°C. Circuit = Typical Application Circuit 2004 Semtech Corp ° SC1403 PRELIMINARY =-40 to 85°C. Typical values are United States Patent No. 6,377,032 www.semtech.com ...
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... POWER MANAGEMENT Electrical Characteristics (Cont.) Unless otherwise noted 15V, both PWMs on, SYNC = 0V, VL load = 0mA, REF load = 0mA, PSAVE +25°C. Circuit = Typical Application Circuit Note: (1) This device is ESD sensitive. Use of standard ESD handling procedures required. (2) Applicable for + 2004 Semtech Corp ...
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... COMP5 5 24 SYNC 6 23 ON5 7 22 GND 8 21 REF 9 20 PSAVE RESET FB5 12 17 CSL5 13 16 CSH5 14 15 (28 Pin TSSOP) Block Diagram 2004 Semtech Corp. Ordering Information ON3 DH3 PHASE3 Note: (1) Only available in tape and reel packaging. A reel contains BST3 2500 devices ...
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... POWER MANAGEMENT Pin Descriptions Note: All logic level inputs and outputs are open collector TTL compatible. 2004 Semtech Corp SC1403 µ United States Patent No. 6,377,032 www.semtech.com ...
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... POWER MANAGEMENT Pin Descriptions (Cont Note: All logic level inputs and outputs are open collector TTL compatible. Block Diagram 2004 Semtech Corp SC1403 PRELIMINARY United States Patent No. 6,377,032 www.semtech.com ...
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... One linear regulator and a precision reference voltage are also provided. The 5V/30mA linear regulator uses battery power to feed the gate drivers; for improved efficiency the 5V switcher output is used instead when available. Semtech’s proprietary Virtual Current Sense TM provides greater advantages in the aspect of stability and signal-to-noise ratio than the conventional current sense method ...
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... Holding the SHDN pin low disables the SC1403, reducing the V+ input current to less than 10uA. When SHDN is high, the part enters standby mode where the VL regulator and VREF are enabled. Turning on either SMPS will put the SC1403 in run mode. 2004 Semtech Corp ...
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... Minimum required inductance is found at maximum Vin, where ripple current is the greatest Vin L min The next standard value is 6.8uH. For the reference design, the Coiltronics DR127-6R8 is used. To specify the output capacitance, the allowable output ripple 2004 Semtech Corp ...
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... 1.3K. This sets the current limit to approximately 10A. Two guidelines must be used when selecting C, R1, and R2: The values of R2 and R1 should not exceed approximately 2004 Semtech Corp. 1.5Kohm. The bias current from the CSH input flows through these resistors and creates an error term. ...
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... IRf7413. The junction tem- perature rise is then 0.556W 50°C/W = 27.8° This is a modest temperature rise special heat sinking is required when laying out the mosfet. 2004 Semtech Corp. P SWITCHING GATE IRMS = 4.88A PGATE = 30mW is the package thermal JA 13 SC1403 United States Patent No ...
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... Output inductor 4.7uH Switching frequency 300kHz Simulated Control-to-Output gain & phase response (up to 100kHz) is plotted below -10 -20 -30 -40 -50 100 1000 f (Hz) 2004 Semtech Corp. 200 150 100 50 0 -50 -100 , TM -150 -200 100 Measured Control-to-Output gain & phase response (up to 100kHz) is plotted below ...
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... Measured feedback gain & phase responses (up to 100kHz) is plotted below -10 -15 100 1000 10000 f (Hz) 2004 Semtech Corp -20 -40 -60 -80 -100 -120 -140 -160 -180 100 1000 100000 Simulated overall gain & phase responses (up to 100kHz) is ted below. 80 ...
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... Measured overall gain & phase response of the single-pole com- pensation using SC1403 is plotted below -10 -20 100 1000 f (Hz) 180 160 140 120 100 -20 100 1000 2004 Semtech Corp. Table I. Recommended compensation cap for different output capacitance < = > µ > 1 10000 100000 10000 100000 16 SC1403 PRELIMINARY ...
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... The load steps are from and 3A to 6A. The applied di/dt is 2.5A/usec. 3.3V PSAVE enabled Vin = 10V, ILoad 3.3V Forced-Continuous Vin = 10V, ILoad 2004 Semtech Corp. 3.3V PSAVE disabled Vin = 10V, ILoad 3.3V PSAVE enabled Vin = 19V, ILoad United States Patent No ...
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... POWER MANAGEMENT Typical Characteristics (Cont.) 3.3V PSAVE disabled Vin = 19V, ILoad 3.3V Forced ContinuousVin = 19V, ILoad 2004 Semtech Corp. 5.0V PSAVE enabled Vin = 10V, ILoad 5.0V PSAVE disabled Vin = 10V, ILoad United States Patent No. 6,377,032 SC1403 PRELIMINARY www.semtech.com ...
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... POWER MANAGEMENT Typical Characteristics (Cont.) 5.0V Forced Continuous Vin = 10V, ILoad 5.0V PSAVE enabled Vin = 19V, ILoad 2004 Semtech Corp. 5.0V PSAVE disabled Vin = 19V, ILoad 5.0V Forced Continuous Vin = 19V, ILoad United States Patent No. 6,377,032 SC1403 www.semtech.com ...
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... D3 I5in D5 Iin Icap 2004 Semtech Corp. As the input voltage is reduced, the duty cycle of both converters increases. For all input voltages less than 8. impossible to prevent overlap when producing 3.3V and 5V outputs, regardless of the phase relationship between the two converters. Overlap can be seen in the following figure. ...
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... Schottky diode close to each other to reduce the current ramp-up and ramp-down time due to parasitic inductance between the channel of the mosfet 2004 Semtech Corp. and the Schottky diode. The current rating of the Schottky diode can be determined by the following equation: ...
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... Semtech recommends the following circuit for measuring the ov- ervoltage trip point. D1 prevents the output voltage from damag- ing lab supply 1. R1 limits the amount of energy that can be cycled from the output to the input ...
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... POWER MANAGEMENT Typical Characteristics 5.03 5.02 5.01 5.00 4. 3.34 3.33 3.32 3. 2004 Semtech Corp. 5V Line Regulation Vin (V) 3.3V Line Regulation Vin (V) 23 SC1403 5V@0A 5V@3A 5V@ 3.3V@ 0A 3.3V@ 3A 3.3V United States Patent No. 6,377,032 www.semtech.com ...
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... Semtech Corp. 5V Load Regulation @Vin =19V Iout (A) 5V Load Regulation @ Vin =10V Iout (A) 24 SC1403 PRELIMINARY 5V @ 25degC 5V @ 125degC 5V@ -45degC 5 6 5.0V@ 25degC 5.0V@ 125degC 5.0V@ -45degC ...
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... POWER MANAGEMENT Typical Characteristics (Cont.) 3.35 3.34 3.33 3.32 3.31 3.30 3.29 0 3.34 3.33 3.32 3.31 3.30 3.29 3.28 0 2004 Semtech Corp. 3.3V Load Regulation @ Vin = 19V Iout (A) 3.3V Load Regulation @ Vin =10V Iout (A) 25 SC1403 3.3V@ 25degC 3.3V@ 125degC 3.3V@ -45degC ...
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... POWER MANAGEMENT Typical Characteristics (Cont.) 97% 95% 93% 91% 89% 87% 85% 0.01 95% 90% 85% 80% 75% 70% 0.01 2004 Semtech Corp. 5V Efficiency 0.1 1 Iout (A) 3.3V Efficiency 0.1 1 Iout (A) 26 SC1403 PRELIMINARY 5V@ 19Vin 5V@ 10Vin 10 3.3V@ 19Vin 3.3V@ 10Vin 10 United States Patent No. 6,377,032 www.semtech.com ...
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... POWER MANAGEMENT Evaluation Board Schematic 2004 Semtech Corp SEQ CSH5 15 14 DH5 CSL5 16 13 PHASE5 FB5 17 12 BST5 RESET 18 11 DL5 PSAVE 19 10 PGND REF GND TIME/ON5 22 7 SHDN SYNC 23 6 DL3 COMP5 24 5 BST3 COMP3 25 4 PHASE3 FB3 26 3 DH3 ...
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... POWER MANAGEMENT Evaluation Board Bill of Materials 2004 Semtech Corp SC1403 PRELIMINARY United States Patent No. 6,377,032 www.semtech.com ...
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... POWER MANAGEMENT Evaluation Board Layout Top Assembly Bottom Assembly 2004 Semtech Corp. 29 United States Patent No. 6,377,032 SC1403 www.semtech.com ...
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... Place the capacitor close to the CSH/CSL pins on the SC1403, and connect to the capacitor using short direct traces. 2004 Semtech Corp. With resistive sensing: minimize the length of current sense signal traces. Keep them less than 15mm. Use Kelvin connections as shown below; keep the traces parallel to each other and as close together as possible ...
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... POWER MANAGEMENT Outline Drawing - TSSOP-28 Land Pattern - TSSOP-28 Contact Information Phone: (805)498-2111 FAX (805)498-3804 2004 Semtech Corp. Semtech Corporation Power Management Products Division 200 Flynn Road, Camarillo, CA 93012 31 SC1403 United States Patent No. 6,377,032 www.semtech.com ...