E-L4978D STMicroelectronics, E-L4978D Datasheet

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... A wide input voltage range be- tween 8V to 55V and output voltages regulated from 3.3V to 50V cover the majority of today’s ap- plications. Features of this new generations of DC- DC converter include pulse-by-pulse current limit, hiccup mode for short circuit protection, voltage ...

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... A capacitor connected between this pin and ground determines the soft start time. When this pin is grounded disables the device (driven by open collector/drain). An external resistor connected between the unregulated input voltage and this pin and a capacitor connected from this pin to ground fix the switching frequency. (Line feed forward is automatically obtained) VCC ...

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... Table 3. Pin Description (continued) N° Pin Name OUT BOOT 7 13 COMP (*) Pins 10, 15 and 16 are not internally, electrically connected to the die. Table 4. Thermal Data Symbol R Thermal Resistance Junction to ambient th(j-amb) (*) Package mounted on board. Table 5. Absolute Maximum Ratings Symbol Minidip S016 V Input voltage Output DC voltage V ...

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... Low level output voltage oL I Source output current o source I Sink output current o sink I Source bias current b SVRR E/A Supply voltage ripple rejection DC open loop gain g Transconductance m 4/13 = 20kΩ 24V, unless otherwise specified). “ CC Test Condition V = 3.3 to 50V 0. 0 55V 10V; I ...

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... C1=220µF/63V EKE C2=2.7nF C5=100nF C6=100nF C7=220nF/63V C8=330µF/35V CG Sanyo L1=126µH KoolMu 77120 - 55 Turns - 0.5mm R1=20K R2=9.1K D1=STPS3L60U Figure 5. PCB and component layout of the figure 4. = 20kΩ 24V, unless otherwise specified). “ CC Test Condition 55V cc Duty Cycle = 13kΩ ...

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... D97IN724 100KHz R =20K 1 C =2.7nF 2 0Hz Vcc(V) Figure 10. Load regulation . D97IN731 200KHz R =22K 1 C =1.2nF 2 =20K 1 =2.7nF 2 0Hz Figure 11. Switching frquency vs. R1 and C2 . D97IN732 Tj=125˚C ( (V) 3.377 Tj=125˚C 3.376 3.375 Tj=25˚C 3.374 3.373 3.372 3.371 3.370 (V) V 3.378 CC 3.376 3 ...

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... V Figure 13. Switching frequency vs. junction temperature. fsw (KHz) 105 100 Figure 14. Dropout voltage between pin 5 and 4. ∆ V (V) 0.7 0.6 0.5 0.4 0.3 0.2 0.1 0.0 0.0 0.2 0.4 0.6 0.8 1.0 1.2 1.4 Figure 15. Efficiency vs output voltage. . ...

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... Vcc [V] 8/13 Figure 21. Power dissipation vs. Vcc. . D97IN740 V =8V CC fsw=200KHz V =5.1V O (A) O Figure 22. Device Power dissipation vs D97IN741 fsw=200KHz V =3.36V O (A) O Figure 23. Pulse by pulse limiting current vs. junction temperature Pdiss [mW] 1000 Vo=5.1V fsw=100kHz 800 Io=2A 600 Io=1.5A 400 Io=0.5A 200 Vcc [V] Pdiss [mW] 1400 ...

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... Figure 26. Soft start capacitor selection Vs inductor and V . ccmax L 680nF (µH) fsw=100KHz 400 300 200 100 Figure 27. Soft start capacitor selection Vs inductor and V Figure 28. Open loop frequency and phase of error amplifier . GAIN D97IN786 (dB -50 (mV 100 = 100KHz -100 0 -150 -100 -200 D97IN745 ...

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... L4978 3 Package Informations Figure 29. DIP-8 Mechanical Data & Package Dimensions mm DIM. MIN. TYP. MAX. A 3.32 a1 0.51 B 1.15 1.65 b 0.356 0.55 b1 0.204 0.304 D 10.92 E 7.95 9.75 e 2.54 e3 7.62 e4 7.62 F 6.6 I 5.08 L 3.18 3.81 Z 1.52 10/13 inch MIN. TYP. MAX. 0.131 0.020 0.045 ...

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... L 0.40 1.27 k 0˚ (min.), 8˚ (max.) ddd 0.10 (1) “D” dimension does not include mold flash, protusions or gate burrs. Mold flash, protusions or gate burrs shall not exceed 0.15mm per side. inch MIN. TYP. MAX. 0.093 0.104 0.004 0.012 ...

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... L4978 Table 7. Revision History Date Revision October 2001 May 2005 12/13 8 First Issue 9 Modified D1 on the Fig. 4. Description of Changes ...

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