SC4525DSETRT Semtech, SC4525DSETRT Datasheet
SC4525DSETRT
Specifications of SC4525DSETRT
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SC4525DSETRT Summary of contents
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... Fig.1b: 350kHz 10-16V to 5V/3A Step-Down Converter (Front Page Efficien SC4525A 4148 OUT 10 mH 5V/3A R4 33. 20BQ030 8.25k 47mF Efficiency of the 1MHz 10V-28V to 5V/3A Step-Down Converter (Front Pag Down Converter ( Front Page Schematic SC4525D Switching Regulator Efficiency =12V 0.5 1 1.5 2 2.5 Load Current (A) www.semtech.com ...
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... Pin SOIC - EDP) Marking Information yyww=Date code (Example: 0752) xxxxx=Semtech Lot No. (Example: E9010) © 2011 Semtech Corp. Ordering Information Device SC4525DSETRT BST SC4525DEVB FB Notes: COMP (1) Available in tape and reel only. A reel contains 2,500 devices. (2) Available in lead-free package only. Device is fully WEEE and RoHS SS/EN compliant and halogen-free ...
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... COMP Source Current COMP Sink Current Internal Power Switch Switch Current Limit Switch Saturation Voltage © 2011 Semtech Corp. Thermal Information Junction to Ambient Junction to Case Maximum Junction Temperature……………………… 150°C Storage Temperature ………………………… -65 to +150°C Lead Temperature (Soldering) 10 sec … ...
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... Hiccup Arming SS/EN Voltage Hiccup SS/EN Overload Threshold Hiccup Retry SS/EN Voltage Over Temperature Protection Thermal Shutdown Temperature Thermal Shutdown Hysteresis Note 1: Switch current limit does not vary with duty cycle. © 2011 Semtech Corp. = 2.2V, -40°C < < 125° 60.4kΩ ...
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... V The exposed pad serves as a thermal contact to the circuit board soldered to the ground plane of the 9 Exposed Pad PC board. © 2011 Semtech Corp. falls below 0.8V, then the switching frequency will be reduced order to fully enhance the internal NPN power transistor. IN SC4525D www ...
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... V1 V1 FREQUENCY FREQUENCY FOLDBACK FOLDBACK ROSC ROSC SS/EN SS/ REFERENCE REFERENCE & THERMAL & THERMAL SHUTDOWN SHUTDOWN SS/EN SS/EN FAULT FAULT Figure 3. Soft-start and Overload Hiccup Control Circuit © 2011 Semtech Corp. SLOPE SLOPE + + COMP COMP PWM PWM - - OSCILLATOR OSCILLATOR 1.2V 1. ...
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... SS270 REV 6-7 Switch Saturation Voltage vs Switch Current 500 450 o 400 125 350 300 o 250 25 C 200 150 100 50 0.0 0.5 1.0 1.5 2.0 2.5 3.0 3.5 4.0 4.5 Switch Current (A) © 2011 Semtech Corp. (3) 3.3Vin Eff SC4525B Efficiency (6) Foldback Freq vs Temp ...
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... Temperature ( V Quiescent Current 2.5 o 125 C 2.0 o -40 1.5 1.0 0.5 0 (V) IN © 2011 Semtech Corp. Curve 12 SS270 REV 6-7 V Supply Current IN vs Soft-Start Voltage 2.5 125 2.0 o -40 1.5 1.0 (15) SS charge cur vs SS volt 0.5 0 100 125 V (V) ...
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... Pulling the SS/EN pin below 0.2V shuts off the regulator and reduces the input supply current to 18µA (V When the SS/EN pin is released, the soft-start capacitor © 2011 Semtech Corp. is charged with an internal 1.9µA current source (not shown in Figure 3). As the SS/EN voltage exceeds 0.4V, ...
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... ⋅ ⋅ ⋅ ⋅ © 2011 Semtech Corp ⋅ ⋅ − − where V voltage, and V diode. In peak current-mode control, the PWM modulating ramp is the sensed current ramp of the power switch. will recharge This current ramp is absent unless the switch is turned C on ...
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... input capacitance can be estimated from > > ⋅ D ⋅ ⋅ ⋅ © 2011 Semtech Corp. > > ⋅ D ⋅ ⋅ ⋅ where − − Multi-layer ceramic capacitors, which have very low ESR (a few mW) and can easily handle high RMS ripple current, are ...
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... Temperature ( Temperature ( Figure 5. Typical Minimum Bootstrap Voltage required to Saturate the Transistor (I © 2011 Semtech Corp. For the bootstrap circuit, a fast switching PN diode (such as 1N4148 or 1N914) and a small (0.33µF – 0.47µF) ceramic capacitor is sufficient for most applications. When bootstrapping from 2.5V to 3.0V output voltages, use a ...
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... ≈ ≈ PWM PWM ⋅ ⋅ PWM PWM ⋅ ⋅ ESR zero © 2011 Semtech Corp ⋅ π ⋅ π ⋅ ⋅ ⋅ ⋅ ⋅ ⋅ 600 600 ⋅ π ⋅ π ⋅ ⋅ ⋅ ⋅ PWM PWM ESR ...
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... C C − − 18.5 18.5 ⋅ ⋅ ⋅ ⋅ ⋅ π ⋅ π ⋅ ⋅ Then the compensator parameters are © 2011 Semtech Corp. ⋅ ⋅ ⋅ ...
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... The exposed pad should be soldered to a large ground plane as the ground copper acts as a heat sink for the device. To ensure proper adhesion to the ground plane, avoid using vias directly under the device. © 2011 Semtech Corp. (13 ⋅ ...
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... Table 4. Recommended inductance (L Typical Applications Vin(V) Vo(V) Io(A) 1.0 3.3 2.0 1.5 5 2.5 3.3 1.5 2.5 12 3.3 5 7.5 © 2011 Semtech Corp. ) and compensation network ( and compensator (R 1 Recommended Parameters C2(uF) L1(uH) R7(k) 3.3 3.74 2.2 6.49 3.3 3.74 4.7 6.49 4.7 7 ...
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... L1 : CoiltronicsDR73 - 4R7 Figure 10. 350kHz 5V to 2.5V/3A Step-down Converter 3. 4.7mF Fig. 10: 350 kHz 2.5V/3 A Step Down Converte SS/EN COMP Coiltronics DR73 - 3R3 Figure 11. 350kHz 3.3V to 1.5V/3A Step-down Converter © 2011 Semtech Corp. C1 0.33m F BST IN SW SC4525D FB RSET GND 60.4k 6.49 k CMSH3 - 20M C5 4 ...
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... Load Current (A) Figure 12(a). Load Characteristic 5V Output Response (1V/DIV, AC Coupling) Inductor Current (1A/DIV) 40us/DIV Figure 12(c). Load Transient Response (I = 0.3A to 3A) O © 2011 Semtech Corp. Fig.12b: SS 12V Input (5V/DIV) 5V Output (2V/DIV) SS Voltage (1V/DIV) 3 3.5 4 Fig.12d: OCP Figure 12(b). V Figure 12(d). Output Short Circuit (Hiccup) ...
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... N/2 TIPS aaa C SEATING PLANE C EXPOSED PAD NOTES: 1. CONTROLLING DIMENSIONS ARE IN MILLIMETERS (ANGLES IN DEGREES). -A- 2. DATUMS AND 3. DIMENSIONS "E1" AND "D" DO NOT INCLUDE MOLD FLASH, PROTRUSIONS OR GATE BURRS. REFERENCE JEDEC STD MS -012, VARIATION BA. 4. © 2011 Semtech Corp e bxN bbb C A-B D ...
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... CONSULT YOUR MANUFACTURING GROUP TO ENSURE YOUR COMPANY'S MANUFACTURING GUIDELINES ARE MET. 2. REFERENCE IPC-SM-782A, RLP NO. 300A. 3. THERMAL VIAS IN THE LAND PATTERN OF THE EXPOSED PAD SHALL BE CONNECTED TO A SYSTEM GROUND PLANE. FAILURE MAY COMPROMISE THE THERMAL AND/OR FUNCTIONAL PERFORMANCE OF THE DEVICE. © 2011 Semtech Corp. E SOLDER MASK D DIM ...
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... PLICATIONS IS UNDERSTOOD TO BE UNDERTAKEN SOLELY AT THE CUSTOMER’S OWN RISK. Should a customer purchase or use Semtech products for any such unauthorized application, the customer shall indemnify and hold Semtech and its officers, em- ployees, subsidiaries, affiliates, and distributors harmless against all claims, costs damages and attorney fees which could arise. ...