SC1458 SEMTECH [Semtech Corporation], SC1458 Datasheet

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... Both versions of the SC1458 require an input voltage level between 2.5V and 5.5V. The SC1458A supplies 2.5V on OUTA and 1.8V on OUTB, while SC1458B supplies 2.85V on both outputs. (For other voltage options see the SC560). The SC1458A provides a PGOOD output to hold a processor in reset when the voltage on OUTA is not in regulation ...

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... SC1458BWLTRT SC1458AEVB 6 SC1458BEVB Notes: 5 (1) Available in tape and reel only. A reel contains 3,000 devices. (2) Available in lead-free package only. Device is WEEE and RoHS compliant. 4 Voltage Options Device SC1458A SC1458B SC1458 Package (1)(2) MLPD-W6 3x3 (1)(2) MLPD-W6 3x3 Evaluation Board Evaluation Board Marking LDOA ...

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... BYP 3.7V 50mA , 10Hz < f < 100kHz IN OUT = 25°C. All specifi cations A Min Typ 2 300mA -3 300 = 2.5V 100 0.1 = 25°C 100 A MAX -6 350 50 300 SC1458 < +85 A < 5.5 IN (2) (°C/ Max Units 5 200 mV 1 μA μ 850 mA μV RMS μV ...

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... Logic Input High Threshold Logic Input Low Threshold Logic Input High Current Logic Input Low Current Digital Outputs PGOOD Output Voltage Low Notes: (1) Dropout voltage is defi ned OUT (2) SC1458B only (3) SC1458A only Conditions V = 3.7V 50mA 1kHz, IN OUT C = 22nF PSRR ...

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... T = ° 100 150 Output Current (mA) Line Regulation LDOB V = 2.85V 1mA OUTB OUTB T =-40° =25° =85°C A 2.7 2.9 3.1 3.3 3.5 3.7 3.9 4.1 4.3 4.5 4.7 4.9 5.1 5.3 5.5 Input Voltage (V) Dropout Voltage LDOB V = 2.85V 200mA OUTB OUTB T=85 ° T=25 C T=-40 2.2 2.25 2.3 2.35 2.4 2.45 2.5 2.55 2.6 Input Voltage (V) SC1458 200 250 ° C ° C 2.65 2.7 2.75 2.8 5 ...

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... PSRR vs. Frequency V = 2.85V 50mA, C =22nF OUT O BYP 0 10 100 1000 Frequency (Hz) Output Noise vs. Load Current V = 2.85V 50mA, C =22nF OUTB O BYP T=85 ° C T=25 ° C ° T=- 100 150 Output Current (mA) Load Transient Response (Falling Edge 2.5V 3.6V OUT IN Time (1ms/div) SC1458 10000 200 250 6 ...

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... Input supply voltage terminal Output for LDOA Analog and digital ground Logic Input — active high enables the SC1458. Open drain logic output — monitors output of LDOA, switches low when the output drops out of regulation. LDO bypass output — bypass with a 22nF capacitor. ...

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... Block Diagram VIN 2 GND 4 Power On And Bandgap Control Reference Logic SC1458A ENA LDOA ENB LDOB SC1458 5 EN SC1458B BYP or 6 PGOOD 3 OUTA 1 OUTB 8 ...

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... SC1458B. The SC1458A version has pin 6 confi gured as a power good signal (PGOOD), which monitors the output of LDOA. The SC1458B device has pin 6 confi gured as an external bypass pin (BYP). This is suitable for applications which require low output noise and excellent PSRR characteristics ...

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... T = Ambient Temperature (° Power Dissipation (W) D θ = Thermal Resistance Junction to Ambient (°C/W) JA Example An SC1458A is used to provide outputs of 2.5V, 150mA from LDOA and 1.8V, 200mA from LDOB. The input voltage is 4.2V, and the ambient temperature of the system is 60° 0.15(4.2 – 2.5) + 0.2(4.2 – 1. 0.74W and (0.74 x 50) = 97°C ...

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... Connect all ground connections directly to the ground plane whenever possible to minimize ground potential diff erences on the PCB. • Ensure that the feedback resistors are placed as close as possible to the feedback pins. there are C SC1458B OUTB OUTA SC1458 C BYP 11 ...

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... MIN NOM MAX MIN NOM A .028 .030 .031 0.70 0.75 A1 .000 .001 .002 0.00 0.02 (.008) (0.20 .012 .016 .018 0.30 0.40 D .114 .118 .122 2.90 3.00 E .114 .118 .122 2.90 3.00 D1 .087 .091 .094 2.20 2.30 E1 .055 .059 .063 1.40 1.50 e .037 BSC 0.95 BSC L .012 .014 .016 0.30 0. aaa .003 0.08 bbb .004 0.10 C SC1458 MAX 0.80 0.05 0.45 3.10 3.10 2.40 1.60 0.40 12 ...

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... FUNCTIONAL PERFORMANCE OF THE DEVICE. Contact Information DIM Semtech Corporation Power Mangement Products Division 200 Flynn Road, Camarillo, CA 93012 Phone: (805) 498-2111 Fax: (805) 498-3804 www.semtech.com SC1458 DIMENSIONS INCHES MILLIMETERS (.116) (2.95) .087 2.20 .094 2.40 .063 1.60 .037 0.95 .009 0.225 .018 0.45 .030 0.75 ...