CS5171 ON Semiconductor, CS5171 Datasheet
CS5171
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CS5171 Summary of contents
Page 1
... CS5174 1.5 A 280 kHz/560 kHz Boost Regulators The CS5171/2/3/4 products are 280 kHz/560 kHz switching regulators with a high efficiency, 1.5 A integrated switch. These parts operate over a wide input voltage range, from 2 The flexibility of the design allows the chips to operate in most power supply configurations, including boost, flyback, forward, inverting, and SEPIC ...
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... MAXIMUM RATINGS Pin Name Pin Symbol IC Power Input Shutdown/Sync Loop Compensation Voltage Feedback Input (CS5171/3 only) Negative Feedback Input (transient, 10 ms) (CS5172/4 only) Test Pin Power Ground Analog Ground Switch Input CS5171, CS5172, CS5173, CS5174 R2 3. PGND ...
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... 1 NFB = -3 sinks Reduce V from 1.5 V until switching stops C CS5171/ NFB = -1.9 V CS5171/ NFB = 0 V CS5171/2 CS5173/ NFB = -1.9 V CS5173/ NFB = 0 V CS5173/4 Frequency drops to reduced operating frequency Frequency drops to reduced operating ...
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... ELECTRICAL CHARACTERISTICS (continued) Commercial Grade < T < 125 C; For all CS5171/2/3/4 specifications unless otherwise stated.) J Characteristic Power Switch Switch Saturation Voltage Switch Current Limit Minimum Pulse Width Switch Leakage General Operating Current Shutdown Mode Current Minimum Operation Input Voltage ...
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... CS5171, CS5172, CS5173, CS5174 Package Pin Number 8 LEAD SO NARROW (continued Shutdown 2.0 V Regulator Delay Timer Sync SS 200 k Negative 2.0 V Error Amp 250 k NFB + CS5172/4 - only -0.65 V Detector 0.4 V Detector FB - CS5171/3 + only Positive Error Amp 1.276 V AGND PACKAGE PIN DESCRIPTION Pin Symbol Pin Symbol V Input power supply pin ...
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... CS5171, CS5172, CS5173, CS5174 TYPICAL PERFORMANCE CHARACTERISTICS 7.2 7.0 6.8 6.6 6.4 6.2 6.0 5.8 5 Temperature ( C) Figure 3. I (No Switching) vs. Temperature CC 1200 1000 800 600 400 200 0 500 I (mA) SW Figure 5. V vs. I CE(SAT) 285 280 275 270 265 260 255 0 50 Temperature ( C) Figure 7. Switching Frequency vs. Temperature (CS5171/2 only ...
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... 1.272 1.270 1.268 0 50 Temperature ( C) Figure 11. Reference Voltage vs. Temperature (CS5171/3 only) 0.20 0.18 0.16 0.14 0.12 0.10 0.08 0 Temperature ( C) Figure 13. I vs. Temperature (CS5171/3 only) FB CS5171, CS5172, CS5173, CS5174 100 420 450 -550 Figure 10. Switching Frequency vs -2.42 -2.43 -2.44 -2. ...
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... CS5171, CS5172, CS5173, CS5174 2.60 2.50 2. Temperature ( C) Figure 15. Current Limit vs. Temperature 1.7 V High Clamp Voltage C 1.5 1.3 1.1 V Threshold 0 Temperature ( C) Figure 17. V Threshold and High Clamp C Voltage vs. Temperature 160 140 120 100 Temperature ( C) Figure 19. Shutdown Delay vs. Temperature ...
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... CS5171, CS5172, CS5173, CS5174 (V) IN Figure 21. I vs. V During Shutdown CC IN 190 180 170 160 150 140 130 120 110 100 0 50 Temperature ( C) Figure 23. Negative Error Amplifier Transconductance vs. Temperature (CS5172/4 only) 100 -20 -40 -60 -200 -150 ...
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... CS5171, CS5172, CS5173, CS5174 APPLICATIONS INFORMATION The oscillator is trimmed to guarantee an 18% frequency accuracy. The output of the oscillator turns on the power switch at a frequency of 280 kHz (CS5171/2) or 560 kHz (CS5173/4), as shown in Figure 27. The power switch is turned off by the output of the PWM Comparator. V ...
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... Therefore, SW current conducts directly from the input power source to the CS5171, CS5172, CS5173, CS5174 output through the inductor and diode. Once V approximately 1.5 V, the internal power switch briefly turns on. This is a part of the CS517x’s normal operation. The ...
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... NFB pin, the equation for calculating output voltage is: *2.5 (R1 ) R2) *V OUT + R2 CS5171, CS5172, CS5173, CS5174 -V OUT Figure 33. Negative Error Amplifier and NFB Pin It is shown that less than 10 k, the deviation from the design target will be less than 0 the tolerances of ...
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... OUT * RIPPLE + (f)(L)(V OUT) where 280 kHz for CS5171/2 and 560 kHz for CS5173/4. The peak inductor current is equal to average current plus half of the ripple current, which should not cause inductor saturation. The above equation can also be referenced when selecting the value of the inductor based on the tolerance of the ripple current in the circuits ...
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... A simple diode clamp, as shown in Figure 37, clamps the V voltage to a diode drop above the voltage on resistor R3. C Unfortunately, such a simple circuit is not generally acceptable loosely regulated. IN CS5171, CS5172, CS5173, CS5174 V IN OUT ripple is small L ESR 1 (C OUT )(f) Figure 37 ...
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... Soft Start R3 Through the addition of an external circuit, a soft-start function can be added to the CS5171/2/3/4 family of components. Soft-start circuitry prevents the V slamming high during startup, thereby inhibiting the inductor current from rising at a high slope. SW http://onsemi ...
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... D1 should be connected Calculating Junction Temperature To ensure safe operation of the CS5171/2/3/4, the designer must calculate the on-chip power dissipation and determine its expected junction temperature. Internal thermal protection circuitry will turn the part off once the junction temperature exceeds 180 C repeated operation at such high temperatures will ensure a reduced operating life ...
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... V pins - designers are referred to ON Semiconductor applications note AND8036/D for more information on properly sizing a copper area. CS5171, CS5172, CS5173, CS5174 Circuit Layout Guidelines In any switching power supply, circuit layout is very JA important for proper operation. Rapidly switching currents combined with trace inductance generates voltage transitions that can cause problems ...
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... CS5171, CS5172, CS5173, CS5174 R2 4. Test C1 3 0.01 F NFB 5 1.27 k 5.0 k Figure 41. Additional Application Diagram Inverting Converter 3 GND PGND (7) AGND ( 0.1 F 200 pF 5.0 k Additional Application Diagram, Figure 42 PGND ...
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... CS5171, CS5172, CS5173, CS5174 1 GND PGND (7) AGND ( 4.7 nF 2.0 k Figure 43. Additional Application Diagram, 2 Input, +12 V/ 200 mA Output Flyback Converter GND 5.0 k 2.2 F 200 pF . Figure 44. Additional Application Diagram, -9 -28 V Input, -5.0 V/700 mA Output Inverted Buck Converter V CC ...
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... Figure 46. Additional Application Diagram, 4.0 V Input, 100 Output Boost Converter with 200 5 Test +5.0 V GND Figure 47. Additional Application Diagram, 5.0 V Input, CS5171, CS5172, CS5173, CS5174 1N4148 1N4148 1N4148 ...
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... CS5171, CS5172, CS5173, CS5174 Device CS5171ED8 CS5171EDR8 CS5172ED8 CS5172EDR8 CS5173ED8 CS5173EDR8 CS5174ED8 CS5174EDR8 CS5171GD8 CS5171GDR8 CS5172GD8 CS5172GDR8 CS5173GD8 CS5173GDR8 CS5174GD8 CS5174GDR8 ORDERING INFORMATION Operating Temperature Range Package -40 C < < T < 125 C < 125 SO < < T < 125 C < ...
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... CS5171, CS5172, CS5173, CS5174 - 0.25 (0.010 - SEATING PLANE - 0.25 (0.010 PACKAGE DIMENSIONS SO-8 D SUFFIX CASE 751-07 ISSUE 0.10 (0.004 http://onsemi.com 22 NOTES: 1. DIMENSIONING AND TOLERANCING PER ANSI Y14.5M, 1982. 2. CONTROLLING DIMENSION: MILLIMETER. ...
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... Notes CS5171, CS5172, CS5173, CS5174 http://onsemi.com 23 ...
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... Phone: 303-675-2175 or 800-344-3860 Toll Free USA/Canada Fax: 303-675-2176 or 800-344-3867 Toll Free USA/Canada Email: ONlit@hibbertco.com N. American Technical Support: 800-282-9855 Toll Free USA/Canada CS5171, CS5172, CS5173, CS5174 JAPAN: ON Semiconductor, Japan Customer Focus Center 2-9-1 Kamimeguro, Meguro-ku, Tokyo, Japan 153-0051 Phone: 81-3-5773-3850 ON Semiconductor Website: http://onsemi.com For additional information, please contact your local Sales Representative ...