NCP3123QPBCKGEVB ON Semiconductor, NCP3123QPBCKGEVB Datasheet
NCP3123QPBCKGEVB
Specifications of NCP3123QPBCKGEVB
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NCP3123QPBCKGEVB Summary of contents
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NCP3123 Dual 3.0 A, Step-Down DC/DC Switching Regulator The NCP3123 is a dual buck converter designed for low voltage applications requiring high efficiency. This device is capable of producing an output voltage as low as 0.8 V. The NCP3123 provides ...
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COMP 1 Error Amplifier FB 1 EOTA Soft Start & Tracking Control (MUX1) TRACK 1 RT ref (0.8 V) SEQ1 Power EN 1 Sequencing 1 Power EN 2 Sequencing 2 SEQ 2 SS2 ...
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PIN DESCRIPTION Pin Symbol 1, 31, 32 SW1 Switch node of Channel 1. Connect an inductor between SW1 and the regulator output. 2 − Input power supply voltage pins. These pins should be connected together to the input ...
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MAXIMUM RATINGS Characteristics Power Supply Voltage Input Signal Supply Voltage Input SW Pin Voltage EN Pin Voltage Input SEQ Pin Voltage Output PG Pin Voltage All Other Pins Thermal Resistance, Junction−to−Ambient (Note 1) Storage Temperature Range Junction Operating Temperature (Note ...
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ELECTRICAL CHARACTERISTICS noted open kW) T Characteristic RECOMMENDED OPERATING CONDITIONS Input Voltage Range SUPPLY CURRENT Quiescent Supply Current Shutdown Supply Current UNDERVOLTAGE LOCKOUT UVLO Threshold UVLO Hysteresis SWITCHING REGULATOR Minimum Duty Cycle Maximum Duty Cycle High Side MOSFET ...
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ELECTRICAL CHARACTERISTICS noted open kW) T Characteristic TRACK Tracking Voltage Range Tracking Voltage Offset Track Bias Current POWER GOOD PG Threshold PG Shutdown Mode PG Delay PG Low Level Voltage PG Hysteresis PG Leakage Current ENABLE/POWER SEQUENCING Enable ...
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TYPICAL OPERATING CHARACTERISTICS 0.813 0.808 0.803 0.798 0.793 0.788 0.783 −50 − TEMPERATURE (°C) Figure 3. Feedback Voltage vs. Temperature 216 211 206 RT = open 201 196 191 186 −50 − TEMPERATURE (°C) ...
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TYPICAL OPERATING CHARACTERISTICS 100 −50 − TEMPERATURE (°C) Figure 7. Shutdown Supply Current vs. Temperature 4.50 4.45 4.40 4.35 4.30 4.25 4.20 −50 − ...
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TYPICAL OPERATING CHARACTERISTICS 9.9 9.4 8.9 8.4 7.9 7.4 6.9 −50 − TEMPERATURE (°C) Figure 13. Soft−Start Discharge Current vs. Temperature 0.6 V TRACK −5 −10 −15 −50 − ...
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TYPICAL OPERATING CHARACTERISTICS 0.45 0.40 0.35 0.30 0.25 0.20 0.15 0.10 0.05 0 −50 − TEMPERATURE (°C) Figure 19. Power Good Saturation Voltage vs. Temperature 0.5 1.0 1.5 2.0 ...
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TYPICAL OPERATING CHARACTERISTICS 90 200 kHz 85 80 500 kHz 75 750 kHz 70 1400 kHz 65 60 2200 kHz 55 0 0.5 1.0 1.5 2.0 I (A) out Figure 25. NCP3123 Efficiency 3.3 ...
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TYPICAL OPERATING CHARACTERISTICS 5.7 5.6 5.5 5.4 5.3 5.2 5.1 5.0 4.9 200 400 600 800 1000 1200 1400 FREQUENCY (kHz) Figure 31. Minimum Input Voltage vs. Operating Frequency, 3A, 1.8 Vout 6 0.1 A 0.5 A 1.0 A 1.5 ...
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Introduction The NCP3123 is a dual channel non−synchronous PWM voltage mode buck regulator. Each channel is identical and has a 3.0 A internal P−FET, compensation, feedback, programmable soft−start, enable and power good pins. These circuits also share the same input ...
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SS capacitor is charged/discharged to a voltage higher than 0.8 V. Power Good The power good is an open drain and active high output that indicates when the output voltage has reached 90% (min) of the nominal ...
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Inductor The output inductor may be the most critical component in the converter because it will directly affect the choice of other components and dictate both the steady state and transient performance of the converter. When choosing inductors, one might ...
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Table 2. Inductor Examples L [mH] Part Number Non−shielded 33 DO5010H−333 PF0382.333NL MSS1278−333 74458133 PF0552.333NL 22 DS5022P−223 P0648.223 74458122 MSS1246T−223 PF0382.223NL 15 DO3316P−153 P0751.153NL MSS1260T−153 74459115 74458115 10 DO3340P−103 DS5022P−103 7445610 74459010 DO3316P−103 P0751.103NL 9 P1169.123NL 8.2 DS3316T−822 MSS1246−822 6.8 ...
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Table 3. Schottky Diode Example Part Number Description MBRA340T3G Schottky Rectifier MBRS340T3G Schottky Rectifier MBRS330T3G Schottky Rectifier The worst case of the diode average current occurs during maximum ...
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Output Voltage Programming The controller will maintain 0 the feedback pin. Thus resistor divider circuit is placed across the Table 4. Output Voltage Setting V [V] 8 7.5 OUT R [kW] 180 360 1 R [kW] ...
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PLD devices) is drastically reduced. The failure is often a result of high currents flowing to the pins or the high voltage difference between pins. In that case, the signal processors require multiple power supplies generating different voltage levels for ...
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EN1/SEQ1 & EN2/SEQ2 SS1 & SS2 0.8V 90% V FB1 (min) VOUT1 & VOUT2 90% V FB2 (min) PG1 & PG2 Figure 41. Typical Behavior of Ratiometric Sequencing Mode Figure 42. Ratiometric Mode − Power−up Figure 44. Ratiometric Mode − ...
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Sequential Sequencing (First−Up/Last−Down Sequence Configuration) In sequential sequencing mode, the second output voltage starts ramping when the first output voltage is already settled and its power good signal is set. Figure 46 shows the NCP3123’s configuration and standard waveforms. The ...
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Daisy Chain Operation The last−up/first−down power output has its SEQ pin tied to the EN of the first−up/last−down power output. Each output in the chain has its power−up delay set by the ENABLE SEQ DISABLE EN NCP3123 TRACK Vout1 Vout2 ...
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EN1 & SEQ2 SS1 90 (min) VOUT1 Internal PG1 90 VOUT2 (min) Internal PG2 SEQ1 & EN2 SS2 VOUT1 & VOUT2 PG1 PG2 Figure 48. Typical Behavior of Sequential Mode 0.8V 4V 0.8V 4V http://onsemi.com 23 ...
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Figure 49. Sequential Mode − Power−up Figure 51. Sequential Mode − Power−down Figure 52. Daisy Chain of Four Outputs Figure 50. Sequential Mode − Power−down Figure 53. OLM of the 3rd Output in Daisy http://onsemi.com 24 Chain ...
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Tracking Voltage tracking is enabled by applying a ramp voltage to the TRACK pin. When the voltage on the TRACK pin is below 0.8 V, the feedback voltage will regulate to this tracking voltage. When the tracking voltage exceeds 0.8 ...
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EN1/SEQ1 & EN2/SEQ2 SS1 0.8V 90 (min) VOUT1 & SS2 TRACK2 0. (min) VOUT1 90 & VOUT2 (min) PG1 PG2 Figure 55. Typical Behavior of Tracking Configuration 4V http://onsemi.com 26 ...
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Figure 56. Tracking Mode − Power−up Figure 58. Tracking Mode of Four Outputs − Power−up When hiccup overload mode is detected on the slave channel only, the output voltage of the 2nd channel (slave) decreases. After the overload condition ends, ...
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Figure 61. Master Voltage − Start of OLM Figure 63. Master Voltage − Start of Augmented OLM Note: If the overload conditions are detected on the master channel only or on both channels together (master + slave), both output voltages ...
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C13 R10 PG1 Enable PG2 Disable EN1 SEQ1 EN2 SEQ2 TRACK1 TRACK2 R9 GND C16 R21 PG1 PG2 EN1 SEQ1 VOUT1 EN2 VOUT2 VOUT3 SEQ2 VOUT4 TRACK1 TRACK2 R18 GND Figure 65. Mixed Mode, Configuration A http://onsemi.com VIN C3 R8 ...
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Figure 66. Mixed Mode of Four Outputs − Power−up Figure 67. Mixed Mode of Four Outputs − Power−down http://onsemi.com 30 ...
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Mixed Mode B (Normal & Sequencing & Tracking) ENABLE DISABLE Tied high Figure 69. Mixed Mode of Six Outputs − Power−up Out3 Out1 EN EN OUT OUT SEQ SEQ NCP3123 NCP3123 TRACK TRACK Out4 Out2 EN EN OUT OUT SEQ ...
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Normal Operation (No Tracking, No Sequencing) R24 R14 R_TRACK PG1 Enable PG2 Disable EN1 Enable Disable EN2 RT VOUT1 VOUT2 AVIN C13 C3 R13 C12 SW1 PG1 VIN PG2 VIN EN1 VIN SEQ1 NCP3123 VIN EN2 VIN SEQ2 VIN TRACK1 ...
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EN1/SEQ1 EN2/SEQ2 SS1 0.8V SS2 90%VFB (min) VOUT1 90%VFB (min) VOUT2 PG1 PG2 Figure 72. Typical Application Behavior 4V 0.8V 4V http://onsemi.com 33 0.8V 0.8V hyst + delay hyst + delay ...
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Parallel Operation Parallel operation of NCP3123 circuit(s) has several advantages. One of the most important aspects is the capability to deliver a double output current. The major advantage is a reduced output voltage ripple in case of out−of−phase synchronization. The ...
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Figure 74. Parallel Operation of Both Outputs http://onsemi.com 35 ...
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... The GND pin also should be tied to the PCB ground in the area under the IC. for specific requirements, the COMPCALC design tool is available from ON Semiconductor at no charge. Visit http://www.onsemi.com/pub/Collateral/COMPCALC.ZIP to download the self−extracting program for NCP3123 loop compensation design assistance. There is an Excel design tool for component selection ...
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Layout Diagram Figure 75. Typical Layout Diagram http://onsemi.com 37 ...
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Typical Application Circuit R1 R26 R16 75k 3.3k 5.1k PG1 PG1 Enable PG2 PG2 Disable EN1 EN1 Enable SEQ1 Disable EN2 EN2 SEQ2 TRACK1 TRACK2 C13 22n C15 NU R13 C3 4.7k RVIN 100n 100 C12 100n SW1 VIN VIN ...
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Figure 77. PCB Layout Example − Evaluation Board v 2.11 http://onsemi.com 39 ...
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... Vendor Part number ON Semiconductor Vishay RCA1206100R0FKEA Vishay RCA120675KFKEA Vishay RCA120668K0FKEA Vishay RCA120613K0FKEA Vishay RCA12064K70FKEA Vishay RCA120647K0FKEA Vishay RCA120615K0FKEA Vishay RCA12065K10FKEA Vishay RCA12063K30FKEA Kemet C1210C226K4PAC Epcos B37872A5104K060 Epcos B37872A5223K060 Epcos B37871K5221J060 Coilcraft DS3316P−332 ON Semiconductor Shipping† 4000 / Tape & Reel ...
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... X 0.28 *For additional information on our Pb−Free strategy and soldering details, please download the ON Semiconductor Soldering and Mounting Techniques Reference Manual, SOLDERRM/D. N. American Technical Support: 800−282−9855 Toll Free USA/Canada Europe, Middle East and Africa Technical Support: Phone: 421 33 790 2910 Japan Customer Focus Center Phone: 81− ...