SC414MLTRT Semtech, SC414MLTRT Datasheet

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... SC414/SC424 is used output switching regula- tor, the 5V LDO can be used as an initial bias supply for the device. Once the switch regulator output is in the switch over range, the LDO will be bypassed by the switcher output for optimum effi ciency. © 2009 Semtech Corporation SC414/SC424 with 5V LDO 1 ...

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Typical Application Circuit ENABLE LDO RTON 154KΩ V5V C1 C2 1μF 1μF C3 100nF VIN +12V RGND 0 Component CIN 10μF/25V COUT 220μF/15mΩ/6.3V L1 1.5μH/9A All other small signal components (resistors and capacitors) are standard SMT devices ...

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... SC414 and SC424 MLPQ-28; 4x4, 28 LEAD Marking Information SC414 yyww xxxxx xxxxx yyww = Date Code xxxxx = Semtech Lot Number Ordering Information Device SC414MLTRT SC424MLTRT SC414EVB SC424EVB 20 LX Notes: 19 PGND 1) Available in tape and reel only. A reel contains 3000 devices. 2) Lead-free packaging only. Device is WEEE and RoHS compliant, ...

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Absolute Maximum Ratings LX to PGND (V -0 ...

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Electrical Characteristics (continued) Parameter Input Supplies (continued) V5V Supply Current FB Comparator Threshold Frequency Range Bootstrap Switch Resistance Timing On-Time (2) Minimum On-Time (2) Minimum Off -Time Soft-Start (2) Soft-Start Ramp Time Analog Inputs/Outputs VOUT Input Resistance Current Sense Zero-Crossing ...

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Electrical Characteristics (continued) Parameter Power Good Power Good Threshold Start-Up Delay Time (Time between EN going high and PGOOD going high) (2) Fault (noise immunity) Delay Time Leakage Power Good On-Resistance Fault Protection Valley Current Limit Valley Current Limit I ...

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Electrical Characteristics (continued) Parameter Linear Regulator — LDO (not available for V5V < 5V) VLDO Accuracy LDO Current Limit VLDO to VOUT Switch-over Threshold (4) VLDO to VOUT Non-switch-over Threshold VLDO to VOUT Switch-over Resistance LDO Drop Out Voltage (5) ...

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Typical Characteristics Characteristics in this section are based on using the Typical Application Circuit on page 2 (SC414/SC424). Effi ciency vs. Load — Forced Continuous Mode Internally biased 5V 12V, V LDO IN OUT 100 ...

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Typical Characteristics (continued) Characteristics in this section are based on using the Typical Application Circuit on page 2 (SC414/SC424). Frequency vs. Load — Forced Continuous Mode Internally biased 5V 12V, V LDO IN OUT 400 ...

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Typical Characteristics (continued) Characteristics in this section are based on using the Typical Application Circuit on page 2 (SC414/SC424). Ultrasonic Powersave Mode — No Load (SC414 12V 1V 0A OUT ...

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Typical Characteristics (continued) Characteristics in this section are based on using the Typical Application Circuit on page 2 (SC414/SC424). Transient Response — Load Rising (SC414 12V 1V 200mA to 6A OUT OUT ...

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Pin Descriptions Pin # Pin Name Pin Function Feedback input for switching regulator used to program the output voltage — connect to an external resis tor divider from VOUT to AGND. Bias input for internal analog circuits and ...

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Block Diagram V5V 2 V5V AGND D Reference Soft Start Comparator 27 TON 4 VOUT Bypass Comparator Bypass Comparator A 6 VLDO Y B VLDO Switchover MUX PGOOD EN/PSV 22 25 Control & Status Gate Drive On- ...

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Applications Information Synchronous Buck Converter The SC414/SC424 is a step down synchronous DC-DC buck converter with integrated power MOSFETs and a 5V LDO. The device is capable of 6A operation at very high effi - ciency. A space saving 4x4 ...

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Applications Information (continued) This method automatically produces an on-time that is proportional to V and inversely proportional to V OUT Under steady-state conditions, the switching frequency can be determined from the on-time by the following equation OUT SW ...

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Applications Information (continued) is recommended to force 33% of the V5V voltage on the EN/PSV pin to operate in forced continuous mode. When EN/PSV is high (above 45% of the voltage at V5V) for SC414, the switching regulator turns on ...

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Applications Information (continued) Because the on-times are forced to occur at intervals no greater than 40μs, the frequency will not fall far below 25kHz. Figure 5 shows ultrasonic power-save operation. minimum f ~ 25kHz SW FB Ripple Voltage (V ) ...

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Applications Information (continued) V drifts up to due to leakage OUT current flowing into C OUT Smart Power Save Threshold (825mV) FB threshold DH and DL off High-side Drive (DH) Single DH on-time pulse after DL turn-off Low-side Drive (DL) ...

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Applications Information (continued) During soft-start the regulator turns off the low-side MOSFET on any cycle if the inductor current falls to zero. This prevents negative inductor current, allowing the device to start into a pre-biased output. This soft start operation ...

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Applications Information (continued) LDO Switch-Over Operation The SC414/SC424 includes a switch-over function for the LDO. The switch-over function is designed to increase effi ciency by using the more effi cient DC-DC converter to power the LDO output, avoiding the less ...

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Applications Information (continued) Note that it is possible to operate the switcher with the LDO disabled, but the ENL pin must be below the logic low threshold (0.4V maximum). The table below summa- rizes the function of the ENL and ...

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Applications Information (continued) There are two values of load current to evaluate — con- tinuous load current and peak load current. Continuous load current relates to thermal stresses which drive the selection of the inductor and input capacitors. Peak load ...

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Applications Information (continued OUT ON RIPPLE 311 I RIPPLE _ VINMIN Capacitor Selection The output capacitors are chosen based on required ...

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Applications Information (continued) This causes the output current to move from 4.8μs, giving the minimum output capacitance require- ment shown in the following equation ...

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Applications Information (continued) Using Ceramic Output Capacitors When applications use ceramic output capacitors, the ESR is normally too small to meet the previously stated ESR criteria. In these applications it is necessary to add a small virtual ESR network composed ...

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Applications Information (continued) The switching frequency also varies with load current as a result of the power losses in the MOSFETs and the induc- tor. For a conventional PWM constant-frequency con- verter, as load increases the duty cycle also increases ...

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Applications Information (continued) • All other decoupling capacitors must be located as close as possible to the IC. PGND Plane • PGND requires its own copper plane with no other signal traces routed on it. • Copper planes, multiple vias, ...

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Outline Drawing — MLPQ-4x4-28 A PIN 1 INDICATOR (LASER MARK aaa C 0.73±0.10 1.45±0. 0.20 PIN 1 IDENTIFICATION NOTES: 1. CONTROLLING DIMENSIONS ARE IN MILLIMETERS (ANGLES IN DEGREES). 2. COPLANARITY APPLIES TO THE EXPOSED PAD ...

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... COMPANY'S MANUFACTURING GUIDELINES ARE MET. 3. SQUARE PACKAGE-DIMENSIONS APPLY IN BOTH X AND Y DIRECTIONS. Contact Information 1. 2.58 Semtech Corporation Power Management Products Division 200 Flynn Road, Camarillo, CA 93012 Phone: (805) 498-2111 Fax: (805) 498-3804 www.semtech.com SC414/SC424 DIMENSIONS DIM MILLIMETERS (3.95 3. ...