SC403MLTRT Semtech, SC403MLTRT Datasheet
SC403MLTRT
Specifications of SC403MLTRT
Related parts for SC403MLTRT
SC403MLTRT Summary of contents
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... EcoSpeed Regulator with Programmable LDO Description The SC403 is a stand-alone synchronous EcoSpeed power supply which incorporates Semtech’s advanced patent-pending adaptive on-time control architecture to provide excellent light-load efficiency and fast transient response. It features integrated power MOSFETs, a boot- strap switch, and a programmable LDO in a 5x5mm package ...
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... SC403 MLPQ-32; 5x5, 32 LEAD Marking Information SC403 yyww xxxxxx xxxxxx yyww = Date Code xxxxxx = Semtech Lot Number xxxxxx = Semtech Lot Number Ordering Information Device SC403MLTRT SC403EVB 26 25 Notes Available in tape and reel only. A reel contains 3000 devices Lead-free package only. Device is RoHS/WEEE compliant and ...
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Absolute Maximum Ratings LX to PGND (V -0 ...
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Electrical Characteristics (continued) Parameter Input Supplies (continued) VDD Supply Current FB On-Time Threshold Frequency Range Bootstrap Switch Resistance Switching MOSFET Resistance R DSON Timing On-Time Minimum On-Time Minimum Off-Time Soft-Start Soft-Start Current Soft-Start Voltage Analog Inputs/Outputs VOUT Input Resistance Conditions ...
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Electrical Characteristics (continued) Parameter Current Sense Zero-Crossing Detector Threshold Power Good Power Good Threshold Start-Up Delay Time (between PWM enable and PGOOD going high) Soft Start Threshold Fault (noise immunity) Delay Time Leakage Power Good On-Resistance Fault Protection Valley Current ...
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Electrical Characteristics (continued) Parameter Logic Inputs/Outputs (continued) EN/PSV Input for Disabling Switcher EN/PSV Input Bias Current ENL Input Bias Current FBL, FB Input Bias Current Linear Regulator (The LDO is shorted to the VDD pin internally.) FBL Accuracy LDO Current ...
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Detailed Application Circuit-1 ENABLE LDO RTON 130KΩ RLDO1 425KΩ RLDO2 1µF 3.3nF 1µF 75KΩ VIN +12V Component CIN 2 x 10µF/25V COUT 330µF/9mΩ L1 1.5µH/6.7mΩ NOTE: The quantity of 10µF input capacitors required varies with the application requirements. Internal LDO ...
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Detailed Application Circuit-2 RTON 130KΩ 5V 10Ω 1µF 3.3nF 1µF VIN +12V Component CIN 2 x 10µF/25V COUT 330µF/9mΩ L1 1.5µH/6.7mΩ NOTE: The quantity of 10µF input capacitors required varies with the application requirements. External 5V Used as Bias 31 ...
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Typical Characteristics Characteristics in this section are based on using the applicable Detailed Application Circuit. Efficiency vs. Load — Forced Continuous Mode V = 1.5V ENL = 5V, EN/P5V is floating OUT LDO DD 100 80 ...
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Typical Characteristics (continued) Characteristics in this section are based on using the applicable Detailed Application Circuit. Frequency vs. Load — Forced Continuous Mode V = 1.5V ENL = 5V, EN/P5V is floating OUT LDO DD 400 ...
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Typical Characteristics (continued) Characteristics in this section are based on using the applicable Detailed Application Circuit. Ultrasonic Powersave Mode — No Load V = 12V 1.5V 0A OUT OUT LDO (20mV/div) (10V/div) Time (10µs/div) ...
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Typical Characteristics (continued) Characteristics in this section are based on using the applicable Detailed Application Circuit. Output Under-voltage Response — Normal Operation V = 12V 1.5V 0A OUT OUT LDO (10V/div) (500mV/div) ...
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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. Switcher output voltage sense pin — also ...
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Block Diagram VDD AGND D Reference VDD SS 7 Soft Start Comparator 31 TON 2 VOUT Bypass Comparator Bypass Comparator VDD A 3 VDD Y B VLDO Switchover MUX 5 FBL EN/PSV PGOOD 26 29 VDD Control ...
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Applications Information Synchronous Buck Converter The SC403 is a step down synchronous DC-DC buck con- verter with integrated power MOSFETs and a 200mA pro- grammable LDO. The device operates at a current very high efficiency. A ...
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Applications Information (continued) One-Shot Timer and Operating Frequency One-shot timer operation is shown in Figure 2. The FB Comparator output goes high when V internal 750mV reference. This feeds into the gate drive and turns on the high-side MOSFET, and ...
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Applications Information (continued) Note that this control method regulates the valley of the output ripple voltage, not the DC value. The DC output voltage V is offset by the output ripple according to the OUT following equation ...
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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 below ~25kHz. Figure 5 shows ultrasonic PSAVE operation. Minimum f ~ 20kHz SW FB Ripple Voltage ( ...
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Applications Information (continued) Time Figure 7 — Valley Current Limit Setting the valley current limit to 6A results in a peak induc- tor current of 6A plus the peak-to-peak ripple current. In this situation, the average (load) current through the ...
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Applications Information (continued) Output Over-Voltage Protection Over-voltage protection becomes active as soon as the device is enabled. The threshold is set at 750mV + 20% (900mV). When V exceeds the OVP threshold, DL latches FB high and the low-side MOSFET ...
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Applications Information (continued) Figure 10 shows the ENL voltage thresholds and their effect on LDO and switcher operation. ENL voltage LDO on Switcher high 2. 2.4V LDO on Switcher off by V ENL low ...
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Applications Information (continued) In many applications, the EN/PSV pin will be pulled high to the VDD node to allow control of the PWM and LDO ENL pin. If the switch over feature is used, this circuit must be implemented with ...
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Applications Information (continued) The desired switching frequency is 300kHz which results from using components selected for optimum size and cost. A resistor ( used to program the on-time (indirectly TON setting the frequency) using the following equation. t ...
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Applications Information (continued) The design goal is that the output voltage regulation be ±4% under static conditions. The internal 750mV refer- ence tolerance is ±1%. Allowing ±1% tolerance from the FB resistor divider, this allows 2% tolerance due to V ...
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Applications Information (continued) Soft Start Capacitor Selection For a soft-start time ( approximately 3ms, solve the SS following equation for ...
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Applications Information (continued MIN OUT sw Using Ceramic Output Capacitors For applications using ceramic output capacitors, the ESR is normally too small to meet the above ESR criteria. In these applications it is necessary ...
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Applications Information (continued) that frequency tends to falls slightly with increasing input voltage. 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 ...
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Applications Information (continued) PCB Layout Guidelines The optimum layout for the SC403 is shown in Figure 15. This layout shows an integrated FET buck regulator with a maximum current of 6A. The total PCB area is approxi- mately 20 x ...
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Applications Information (continued) AGND Island • AGND should have its own island of copper with no other signal traces routed on this layer that connects the AGND pins and pad of the device to the analog control components. • All ...
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Outline Drawing — MLPQ-5x5-32 A PIN 1 INDICATOR (LASER MARK) A aaa C A1 1.05 1.49 3.61 1. R0.20 PIN 1 IDENTIFICATION e NOTES: 1. CONTROLLING DIMENSIONS ARE IN MILLIMETERS (ANGLES IN DEGREES). 2. COPLANARITY APPLIES TO ...
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Land Pattern — MLPQ-5x5-32 3. (C) 3. NOTES: 1. CONTROLLING DIMENSIONS ARE IN MILLIMETERS (ANGLES IN DEGREES). 2. THIS LAND PATTERN IS FOR REFERENCE PURPOSES ONLY. CONSULT YOUR MANUFACTURING GROUP TO ENSURE YOUR COMPANY'S MANUFACTURING GUIDELINES ...
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... SEMTECH PRODUCTS ARE NOT DESIGNED, INTENDED, AUTHORIZED OR WARRANTED TO BE SUITABLE FOR USE IN LIFE- SUPPORT APPLICATIONS, DEVICES OR SYSTEMS OR OTHER CRITICAL APPLICATIONS. INCLUSION OF SEMTECH PRODUCTS IN SUCH APPLICATIONS IS UNDERSTOOD TO BE UNDERTAKEN SOLELY AT THE CUSTOMER’S OWN RISK. Should a customer ...