l6995s ETC-unknow, l6995s Datasheet
l6995s
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l6995s Summary of contents
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... Rin2 Rin1 5V OSC BOOT HGATE HS PHASE LGATE LS RILIM PGND ILIM GND L6995S NOSKIP VSENSE SS INT VFB VREF C VREF TSSOP20 Part Number L6995S L6995STR DESCRIPTION CIN 5V D BOOT C BOOT OUT L6995S Package TSSOP20 Tape & Reel REV. 1 1/26 ...
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... L6995S Table 2. Absolute Maximum Ratings Symbol GND GND DR DR HGATE and BOOT, to PHASE HGATE and BOOT, to PGND V PHASE PHASE LGATE to PGND ILIM, VFB, VSENSE, NOSKIP, SHDN, PGOOD, OVP, VREF, INT, GND SENSE BOOT, HGATE Maximum Withstanding Voltage Range and PHASE Test Condition:CDF-AEC-Q100-002 “ ...
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... SOFT START SECTION I Soft Start current SS SS Clamp Voltage Soft start active range Description = 0°C to 85°C unless otherwise specified) Test Condition Vout=Vref Fsw=110Khz Iout=1A VFB > VREF VFB > VREF SHDN to GND SHDN to GND V = 0.8V SS L6995S Min. Typ. Max. Unit 1 4.5 5.5 V 4.2 4.4 V 4.1 4.3 V ...
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... L6995S Table 5. Electrical Characteristics (continued 5V amb Symbol Parameter CURRENT LIMIT AND ZERO CURRENT COMPARATOR ILIM input bias current Zero Crossing Comparator Offset Phase-gnd ON TIME Ton On time duration OFF TIME T Minimum off time OFFMIN K /T OSC OFFMIN VOLTAGE REFERENCE ...
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... Figure 4. Functional & Block Diagram VCC OSC VSENSE L6995S OSC VSENSE 5/26 ...
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... L6995S 4 DEVICE DESCRIPTION 4.1 Constant On Time PWM topology Figure 5. Loop block schematic diagram Vin R1 One-shot generator OSC R2 Vsense Vref R4 The device implements a Constant On Time control scheme, where the Ton is the high side MOSFET on time duration forced by the one-shot generator. The on time is directly proportional to VSENSE pin voltage and in- ...
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... DC pole in the control loop. C INT1 DC Error Offset Vref is the output divider ratio given from Eq4 and F OUT is connected between INT pin and ground. C INT2 also provides an AC path INT1 <Vout> Time can be connected between INT pin and INT2 L6995S U INT2 7/26 ...
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... Respect to a traditional PWM controller, that has an internal oscillator setting the switching frequency hys- teretic system the frequency can change with some parameters (input voltage, output current). In L6995S is im- plemented the voltage feed-forward circuit that allows constant switching frequency during steady-sate operation with the input voltage variation ...
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... In order to calculate the output volatge chargin time it should be calculated, before, the output volatrge function versus time. This function can be calculated from the inductor current function; the inductor current function can pin). CC Vss Soft-start active range Maximum current limit SS the NOSKIP pin. CC voltage (where the output current limit SS Time Time ). SS L6995S 9/26 ...
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... L6995S be supposed linear function of the time. R ilim t,C = ------------------------------------------------------------------- the output voltage is given by t,C = ------------------------ - out SS calling V as the V final value, the output charging time can be estimated as: out out V out --------------------------------------------------------------------------- - out SS the minimum C value is given imposing this condition: ...
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... J1. Output current in excess of 20A can be reached dependently on the MOSFET type. The SW1 is used to start the device (when the supplies are already present) and to select the PFM/PWM mode 150°C. If the system temperature is lower the 125nC. MAXLS L6995S G 11/26 ...
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... L6995S Figure 10. Demoboard Schematic Diagram C22 R6 R7 PGOOD OVP L6995S ILIM R8 C21 SS C20 R12 SHDN 5V 5.2 Jumper Connection Table 6. Jumper connection with integrator Component NOINT * This component is not necessary, depends from the output ESR capacitor. See the integrator section. Table 7. Jumper connection without integrator ...
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... DEMOBOARD LAYOUT Real dimensions: 5 7,7 cm (2,28inch X 3, 08inch) Figure 11. PCB layout: bottom side Figure 12. PCB Layout: Top side , C like in the figure 9. Note should be selected with a pole frequency N N Figure 13. Internal ground plane Figure 14. Power & signal plane L6995S 13/26 ...
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... L6995S Table 8. PCB Layout guidelines Goal Low radiation and low magnetic coupling with the adjacent circuitry. Don’t penalty the efficiency. Ensure high accuracy in the current sense system. Reduce the noise effect on IC. Table 9. Component list The component list is shared in two sections: the first for the general-purpose component, the second for power ...
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... TAIYO YUDEN 0.6µH ETQP6F0R6BFA PANASONIC 0.6µH A959ASR60N TOKO 0.6µH DXM1306-R60-T COEV 0.6µH CEP12D38H0R6 SUMIDA STMicroelectronics STMicroelectronics STMicroelectronics STMicroelectronics = 1.25V, F OUT Notes N.M. 25V Output capacitor C8, C9 N.M. Input capacitor Notes Q3 N.M. Q3 N.M. Q4 N.M. 25V Linear regulator = 270kHz with an input voltage around V SW L6995S = 20V with IN 15/26 ...
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... L6995S 6 STEP BY STEP DESIGN V = 20V V = 1.25V I = 20A F IN OUT OUT In this design it is considered a low profile demoboard great attention is given to the components height. 6.1 Input capacitor. A pulsed current (with zero average value) flows through the input capacitor of a buck converter. The AC com- ...
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... ESR (ESR OUT is this power loss (few percent of the rated output power), the required (typically, = 510 ON as STS25NH3LL. ON must be greater than VIN DSS -1 °C for these low-voltage classes) and T the , the higher is the gate ON L6995S ) should be OUT with a MAX moves G 17/26 ...
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... 0.9V. Once output divider and frequency divider have been designed as to ob- OUT REF tain the required output voltage and switching frequency, the following equation gives the smallest input voltage, which allows L6995S to regulate (which corresponds OSC -------------- - ----------------------------- - – ...
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... OVP L6995S PGND ILIM U1 GND NOSKIP VSENSE GNDSENSE SS NOINT INT INT VFB VREF SHDN NOINT C6 TP3 in= ut Vcc J1 C7,C13 VIin GNDin D1 L1 C14,C15 R1 D2 GNDOUT C3 C1 INT L6995S VOUT R3 R2 19/26 ...
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... L6995S 6.11 DEMOBOARD LAYOUT Real dimensions: 4 2.7 cm (1.85inch X1.063inch) Figure 17. Top side components placement Figure 18. Bottom side Jumpers distribution Table 10. Component list Part name RESISTOR R1, R5, R9, R10 CAPACITOR C8, C12 C9 20/26 Figure 19. Top side layout Figure 20. Bottom side layout ...
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... POWER SECTION 10 F C34Y5U1E106ZTE12 TOKIN 330 F EEFUE0D331R PANASONIC 2.7 H DO3316P-272HC COILCRAFT 2.2 H ETQP6H2R2GF PANASONIC 3.3 H DQ7545 COEV STMicroelectronics STMicroelectronics = 1.8V, F OUT 1 ,0 1,5 2,0 2,5 3,0 3 [A] Notes Dual MOSFETS in single package 3 = 250kHz with an input voltage around V SW 4,0 4,5 5 6 out=1 . 70Khz PFM L6995S = 20V and IN 21/26 ...
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... L6995S 7 TYPICAL OPERATING WAVEFORMS The measurements refer to the part list in table 4. V Figure 22. Soft Start with no load. Ch1-> Inductor current Ch2-> Output voltage Figure 23. Soft Start with 20A load. Ch1-> Inductor current Ch2-> Output voltage Ch3-> Soft Start voltage 22/26 = 20V V = 1.25V F ...
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... Khz] 350 300 250 200 P SK/P FM 150 P WM 100 Figure 29. Switching Frequency Vs Input Voltage 150 100 0 L6995S 20 25 PFM 0 23/26 ...
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... L6995S Figure 30. TSSOP20 Mechanical Data & Package Dimensions mm DIM. MIN. TYP. MAX. A 1.20 A1 0.050 0.150 A2 0.800 1.000 1.050 b 0.190 0.300 c 0.090 0.200 D (1) 6.400 6.500 6.600 E 6.200 6.400 6.600 E1 (1) 4.300 4.400 4.500 e 0.650 L 0.450 0.600 0.750 L1 1.000 k 0˚ (min.) 8˚ (max.) aaa 0 ...
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... Table 11. Revision History Date Revision April 2004 1 First Issue Description of Changes L6995S 25/26 ...
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... L6995S Information furnished is believed to be accurate and reliable. However, STMicroelectronics assumes no responsibility for the consequences of use of such information nor for any infringement of patents or other rights of third parties which may result from its use. No license is granted by implication or otherwise under any patent or patent rights of STMicroelectronics. Specifications mentioned in this publication are subject to change without notice ...
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