SC2544MLTRT Semtech, SC2544MLTRT Datasheet
SC2544MLTRT
Specifications of SC2544MLTRT
Related parts for SC2544MLTRT
SC2544MLTRT Summary of contents
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... EN PWRGD 4 21 FB1 FB2 5 20 ERROUT1 ERROUT2 6 19 SS1 SS2 7 18 ILIM1 ILIM2 8 17 BST1 BST2 9 16 DRVH1 DRVH2 10 15 PHASE1 PHASE2 11 14 DRVL1 DRVL2 12 13 PGND PVCC Pinout shown as TSSOP-24. 1 SC2544 VO1 PWGRD FB2 VIN+ VO2 VCC FB2 www.semtech.com ...
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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 Note: This device is ESD sensitive. Use of standard ESD handling precautions is required. Electrical Characteristics o Unless specified =16V, Fs=200KHz . 2005 Semtech Corp > < < < < SC2544 θ θ www.semtech.com ...
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... POWER MANAGEMENT Electrical Characteristics o (Cont.) Unless specified =16V, Fs=200KHz A IIN & & 2005 Semtech Corp SC2544 www.semtech.com ...
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... Note: (1) Guaranteed by design. Pin Configurations FB1 FB1 ERROUT1 ERROUT1 SS1 SS1 ILIM1 ILIM1 BST1 BST1 DRVH1 DRVH1 7 7 © 2005 Semtech Corp & & Ordering Information Notes: (1) Only available in tape and reel packaging. A reel contains 3000 devices for MLPQ-24 package and 2500 de- vices for TSSOP-8 package ...
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... POWER MANAGEMENT Pin Descriptions for SC2544TSTRT (TSSOP 2005 Semtech Corp www.semtech.com SC2544 < ...
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... POWER MANAGEMENT Pin Descriptions for SC2544MLTRT (MLPQ 2005 Semtech Corp SC2544 www.semtech.com < ...
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... Ramp generator - CLK1 ERROUT1 FB1 FB1 E/A - 0.75V + OUT SS1 OUT + - 3R R VCC VCC VIN ENABLE EN ON/OFF VCC UVLO AGND 2005 Semtech Corp. PWM 0.75V + OUT R - Protect UVLO 0.75V Band 10V Band Gap 1 LDO Gap 2 0.75V 0.675V FB1 FB2 7 SC2544 PVCC ...
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... Rosc(KOHM) Figure 1. Switching frequency versus Rosc. © 2005 Semtech Corp During start-up, the reference voltage of the error amplifier equals 30% of the voltage on Css (soft-start capacitor) which is connected between the SS pin and ground. When the controller is enabled (by pulling EN ...
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... MOSFET is turned on, as shown in Fig. 3. VCC 10uA DRVH ILIM + OCP Out DRVL - Figure 2. Block diagram of over current protection. 2005 Semtech Corp Figure 3. OCP comparator timing chart nder V nder V nder Voltage Lock Out (UVL nder V oltage Lock Out (UVL ...
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... The peak current in the inductor becomes (1+ /2)*Io and the RMS current is 2005 Semtech Corp. ep-do ep-do ep-do ep-down The followings are to be considered when choosing inductors. a) Inductor core material: For higher efficiency applications above 300 KHz, ferrite, Kool-Mu and polypermalloy materials should be used. Low-cost ...
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... D Cin 2005 Semtech Corp. Choosing P Choosing P Choosing P Choosing MOSFET Choosing P Main considerations in selecting the MOSFET’s are power dissipation, MOSFETs cost, and packaging. Switching losses and conduction losses of the MOSFET’s are directly related to the total gate charge (C channel on-resistance (R performance of MOSFET’s, the product of the total gate charge and on-resistance is used as a figure of merit (FOM) ...
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... Q gs1 Q gs2 Q gs1 Q gs2 Figure 9. MOSFET switching characteristics 2005 Semtech Corp. In Figure 9, Q the gate-to-source voltage the additional gate charge required for the gs2 switch current to reach its full-scale value I is the charge needed to charge gate-to-drain (Miller) capacitance when V . Switching losses occur during the time interval [ ...
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... Actual temperature measurement of the prototype should be carried out to verify the thermal design. 2005 Semtech Corp. Main Control Loop Design Main Control Loop Design Main Control Loop Design Main Control Loop Design ...
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... Out + E/A 0.75V Fig. 12. Compensation network. 2005 Semtech Corp. A resistive divider is used to program the output volt- age. The top resistor R can be chosen from 20k tom resistor R where 0.75V is the internal reference voltage of the SC2544. The other components of the compensator can be calculated using following design procedure: (1) ...
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... MOSFET’s. These inductances may also ring with the gate capacitance. 5) Put the decoupling capacitor for the gate drive power supplies (BST and PVCC) close to the IC and power ground. 2005 Semtech Corp. Control Section Control Section Control Section Control Section ...
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... POWER MANAGEMENT Typical Application Circuit SC2544MLTRT FB1 C3 4.7n C9 2.2 R10 N.P. 10uF/25V 10uF/25V 0.1uF/25V VO1 L1 R12 28K R15 499 C20 C21 C22 C23 FB1 C19 3.9nF N.P. R17 4.9K N.P. © 2005 Semtech Corp. SC2544 U1 VIN+ C1 1uF/25V 1 24 VIN AGND VCC ...
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... POWER MANAGEMENT Evaluation Board - Bill of Material SC2544MLTRT © 2005 Semtech Corp SC2544 www.semtech.com 6 M ...
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... POWER MANAGEMENT Typical Characteristics Gate waveform Ratiometric start up(connect SS1,SS2 together). Sequential start up (Seperate SS1,SS2). © 2005 Semtech Corp. CH1: TG1 CH2: BG1 CH3: TG2 CH4: BG2 Shut down by pulling down EN pin CH1: EN CH1: EN CH2: VO1 CH2: VO1 CH3: VO2 CH3: VO2 Transient response(0-5A) ...
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... Rosc(KOHM) Operating frequency vs. Rosc 4.5 5.0 5.5 6.0 6.5 7.0 7.5 8.0 8.5 9.0 9.5 RILIM(KOHM) RILIM vs. OCP (Vi=12V). 2005 Semtech Corp. Vin=16V 190 188 186 184 182 180 178 10.5 10.3 10.1 9.9 9.7 9 ...
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... Typical Characteristics (Cont.) 7.0 6.5 6.0 5.5 5 Vin(V) Icc vs. Vin (25 DegreeC). 500 480 460 440 420 400 -40 - (Degree C) DL min Ton vs. Tj (Vin=16V). 100 -40 - (Degree C) Dead time vs. Tj (Vin=16V, DH falling to DL rising). 2005 Semtech Corp 100 120 60 80 100 120 22 SC2544 www.semtech.com ...
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... DIMENSIONS "E1" AND "D" DO NOT INCLUDE MOLD FLASH, PROTRUSIONS OR GATE BURRS. 4. REFERENCE JEDEC STD MO-153, VARIATION AD. Land Pattern - TSSOP-24 X (C) P NOTES: 1. THIS LAND PATTERN IS FOR REFERENCE PURPOSES ONLY. CONSULT YOUR MANUFACTURING GROUP TO ENSURE YOUR COMPANY'S MANUFACTURING GUIDELINES ARE MET. Contact Information 2005 Semtech Corp. A DIM D MIN .002 A2 .031 E/2 b ...
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... CONTROLLING DIMENSIONS ARE IN MILLIMETERS (ANGLES IN DEGREES). COPLANARITY APPLIES TO THE EXPOSED PAD AS WELL AS THE TERMINALS. 2. Land Pattern - MLPQ- 4mm) ( NOTES: 1. THIS LAND PATTERN IS FOR REFERENCE PURPOSES ONLY. CONSULT YOUR MANUFACTURING GROUP TO ENSURE YOUR COMPANY'S MANUFACTURING GUIDELINES ARE MET. Contact Information 2005 Semtech Corp DIM ...