SC189CSKTRT Semtech, SC189CSKTRT Datasheet
SC189CSKTRT
Specifications of SC189CSKTRT
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SC189CSKTRT Summary of contents
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... The SC189 is available in SOT23-5 and a thermally enhanced 2mm x 2mm x 0.6mm MLPD-UT6 package. L 1µH LX 1.20V/1.5A C VOUT OUT 22µF GND 1 2.5MHz, 1.5A Synchronous Step Down Regulator Total PCB Area ~25mm L Chip V OUT C SC189 OUT 0805 Actual Size www.semtech.com SC189 can 2 internal DS(ON 0603 ...
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... Code of the output voltage (Example: C for VOUT=1.20V) oyw = Pin 1 and Datecode (Reference Package Marking Design Guidelines, Appendix A) Top Mark 189 x Marking for SOT23, 5 Lead Package Code of the output voltage (Example: C for VOUT=1.20V) yyww = Datecode (Example: 0852) © 2009 Semtech Corp. Ordering Information SC189xULTRT VOUT 6 SC189xSKTRT GND 5 SC189xEVB ...
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... Load Regulation (2) ΔV Oscillator Frequency Soft-Start Time (2) EN Input High Current © 2009 Semtech Corp. Recommended Operating Conditions VIN Supply Voltage ……………………………… 2.9 to 5.5V Maximum Output Current +0.3V IN Thermal Information +0 ...
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... Thermal Shutdown Hysteresis (2) Notes: (1) The “Output Voltage Tolerance” includes output voltage accuracy, voltage drift over temperature and the line regulation. (2) Guaranteed by design. © 2009 Semtech Corp. <+85 °C; T =125°C; Unless otherwise noted typical values are T A J(MAX) Conditions I EN=GND ...
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... Output Current (A) Total Loss vs. Load Current (V Losses 800 V = 1.50V OUT T =25° 600 400 200 0 0.0 0.3 0.6 Output Current (A) © 2009 Semtech Corp. = 22uF/6.3V for L=1uH. OUT =1.5V) OUT 100% 95% = 5.0V 90% 85% 80% 75% 70% 65% 60% 0.9 1.2 1.5 Efficiency vs. Load Current (V =5 ...
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... Output Current (A) Total Loss vs. Load Current (V Losses 800 V = 1.50V OUT T =25° 600 400 200 0 0.0 0.3 0.6 Output Current (A) © 2009 Semtech Corp. = 22uF/6.3V for L=1uH. OUT Efficiency vs. Load Current (V =1.5V, SOT23-5) OUT 100% 95% = 5.0V 90% 85% 80% 75% 70% 65% 60% 0.9 1.2 1 ...
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... V 0.4% 0.2% 0.0% -0.2% -0.4% V -0. OUT -0. 25° -1.0% 2.5 3.0 3.5 4.0 Input Voltage (V) © 2009 Semtech Corp. = 22uF/6.3V for L=1uH. OUT 20% 15% 10 -5% -10% -15% -20% 4.5 5.0 5.5 1.0% 0. 3.3V OUT 0.6% 0.4% 0.2% 0.0% -0.2% -0 ...
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... C A 400 L= MDT2520-CR1R0M 350 (DCR= 80m_max) 300 250 200 150 100 L= 1071AS-1R0 (DCR=40m_max 0.0 0.3 0.6 Output Current (A) © 2009 Semtech Corp. = 22uF/6.3V for L=1uH. OUT =1.5V) OUT 1.0% 0.8% 0.6% 0. 3.3V IN 0.2% 0.0% -0.2% -0.4% -0.6% -0.8% -1.0% ...
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... IN I =0A OUT Transient Response (V Transient Response (V =1.5V 0.5A) OUT V OUT 100mV/div I OUT 500mA/div V =5.0V 50µs/div IN I =0A to 0.5A OUT © 2009 Semtech Corp OUT =1.5V) =1.5V) OUT OUT V OUT 10mV/div I LX 500mA/div V LX 2V/div =1.5V) =1.5V) OUT OUT V OUT ...
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... Start Up into Pre-Biased Output (V Start Up into Pre-Bias Output (Enable 2V/div V EN 2V/div V OUT 500mV/div V =5.0V 200µs/div IN R =1k OUT © 2009 Semtech Corp OUT =1.5V) =1.5V) OUT 2V/div 2V/div 1V/div =1.5V) OUT 2V/div 500mV/div =1.5V) Enable OUT 2V/div 2V/div 500mV/div 10 = 10uF/6 ...
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... OUT Start Up (V Start Up (Enable)(V OUT OUT V IN 5V/div V EN 2V/div V OUT 1V/div V =5.0V 200µs/div IN R =1k OUT © 2009 Semtech Corp 10uF/6.3V (Murata: GRM21BR60J106K). IN OUT =3.3V) =3.3V) OUT OUT V OUT 10mV/div I 500mA/div V 2V/div =3.3V) Transient Response (V OUT V OUT 100mV/div ...
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... OUT Shutdown-Disable (V Shutdown (Disable 5V/div V EN 2V/div V OUT 2V/div V =5.0V 500µs/div IN R =33 OUT © 2009 Semtech Corp OUT =3.3V) OUT V 2V/div V OUT 1V/div =3.3V)(Enable) Start Up into Pre-Biased Output (V Start Up into Pre-Bias Output (Power Up V OUT V 2V/div V OUT 1V/div =3 ...
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... V =5.0V 500ns/div IN I =0A OUT Transient Response (V Transient Response (V V OUT 20mV/div I OUT 500mA/div V =5.0V 50µs/div IN I =0A to 0.5A OUT © 2009 Semtech Corp. =1.0V) =1.0V) OUT OUT V OUT 10mV/div 1A/div V 2V/div =1.0V) =1.0V) OUT OUT V OUT 10mV/div 1A/div V 2V/div =1.0V) =1.0V) ...
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... VOUT T Not Available Thermal Pad © 2009 Semtech Corp. Pin Function NC No connection. Enable pin. When connected to logic high or tied to VIN pin, the SC189 is on. When con- nected to logic low, the device enters shutdown and consumes less than 1µA of current. ...
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... Block Diagram Internal Oscillator V OVP Voltage VOUT Select 500mV Ref EN © 2009 Semtech Corp. Plimit Comp Plimit Amp Ramp + - Generator OVP - + - - + + Error Amp PWM Comp 15 SC189 + - Current Amp Control Logic www.semtech.com VIN LX GND ...
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... VOUT R SC189A 10k Figure 1 — Typical schematic for adjustable output voltage option from standard 1.0V of SC189A Note: ( optional. © 2009 Semtech Corp. EN (2) R =10k and C =10nF for standard design. FB2 FF shown above. For programming the output voltage from other standard voltage, the R adjusted to meet the equation shown above ...
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... Output Voltage (V) Figure 5 — Current limit holding current decreasing rate vs. output voltage © 2009 Semtech Corp. 125° the current limit holding current for the SC189 to exit foldback current limit mode. Figure 5 shows the typical current limit holding current decreasing rate over differ- ent output voltage ...
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... Wire Wound TOKO 2.8x3.0x1.5(mm) 1.0uH, 80m(max) Multilayer Chip TOKO 2.5x2.0x1.0(mm) Table 2b – Recommended L and output capacitors for Vout=1.8V to 3.3V © 2009 Semtech Corp. A(1.0V),B(1.1V),C(1.2V),E(1.28V),F(1.3V),H(1.5V) Part Number Description 10uF,6.3V 1071AS-2R2N X5R,0805 22uF,6.3V 1071AS-1R0N X5R,0805 22uF,6 ...
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... Magnetic fields associated with the output inductor can interfere with nearby circuitry. This can be minimized by the use of low noise shielded inductors which use the © 2009 Semtech Corp. minimum gap possible to limit the distance that magnetic fields can radiate from the inductor. However shielded inductors typically have a higher DCR and are thus less efficient than a similar sized non-shielded inductor ...
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... OSC I OUT © 2009 Semtech Corp. The input capacitor RMS ripple current varies with the input and output voltage. The maximum input capacitor RMS current is found from the equation I CIN ( RMS The input voltage ripple and RMS current ripple are at maximum when the input voltage is twice the output voltage or 50% duty cycle ...
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... And it will also improve the overall efficiency by reducing the copper losses on the output and ground planes. © 2009 Semtech Corp. (a) Top layer for MLPD-UT6 2x2 package (b) Bottom layer for MLPD 2x2 package Figure 7 — Recommended PCB Top & Bottom Layer Layout for MLPD-UT6 2x2 Package ...
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... THIS LAND PATTERN IS FOR REFERENCE PURPOSES ONLY. CONSULT YOUR MANUFACTURING GROUP TO ENSURE YOUR COMPANY'S MANUFACTURING GUIDELINES ARE MET. 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. © 2009 Semtech Corp DIM ...
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... Outline Drawing – SOT23-5 Land Pattern – SOT23-5 © 2009 Semtech Corp. X DIMENSIONS DIM MILLIMETERS 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 ARE MET. ...
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