L4981X STMicroelectronics, L4981X Datasheet
L4981X
Available stocks
Related parts for L4981X
L4981X Summary of contents
Page 1
... BLOCK DIAGRAM September 1998 POWER FACTOR CORRECTOR MULTIPOWER BCD TECHNOLOGY DIP20 ORDERING NUMBERS: L4981X (DIP20) L4981XD (SO20) trol functions for designing a high efficiency-mode power supply with sinusoidal line current con- sumption. The L4981 can be easily used in systems with mains voltages between 85V to 265V without any line switch ...
Page 2
L4981A - L4981B put filter; both the operating frequency modes working with an average current mode PWM con- troller, maintaining sinusoidal line current without slope compensation. Besides power MOSFET gate driver, precise volt- age reference (externally available), error ampli- fier, ...
Page 3
THERMAL DATA Symbol R Thermal Resistance Junction-ambient th j-amb PIN FUNCTIONS N. Name 1 P-GND Power ground. 2 IPK L4981A peak current limiting. A current limitation is obtained using a single resistor connected between Pin 2 and the sense resistor. ...
Page 4
L4981A - L4981B ELECTRICAL CHARACTERISTICS (Unless otherwise specified 24K , 3.5V, V OSC SS CA-OUT V = GND 1V 1V, T FEED IPK OVP Symbol Prameter ERROR ...
Page 5
ELECTRICAL CHARACTERISTICS (continued) Symbol Parameter SUPPLY VOLTAGE V Operating Supply Voltage CC OVER VOLTAGE PROTECTION COMPARATOR V Rising Threshold Voltage thr V Hysteresis 3Hys I Input Bias Current 3 t Propagation delay to output d OVER CURRENT PROTECTION COMPARATOR V ...
Page 6
L4981A - L4981B ELECTRICAL CHARACTERISTICS (continued) Symbol Prameter MULTIPLIER SECTION Multipler Output Current K Multiplier Gain V 1.28 VA OUT MULT OUT AC V VRMS V OUT LFF REF MULT ...
Page 7
Figure 3: MULTI-OUT vs RMS V = 5.1V) LFFD Figure 5: MULTI-OUT vs RMS V = 2.5V) LFFD Figure 7: MULTI-OUT vs RMS V = 2.5V) LFFD = 4.4V; Figure 4: ...
Page 8
L4981A - L4981B Figure 9A: L4981A Power Factor Corrector (200W FUSE BRIDGE 85V AC -265V R11 PART LIST R 0.07(3 x ...
Page 9
Figure 9B: L4981B Power Factor Corrector (200W) R22 FUSE BRIDGE 85V AC -265V R11 R3 PART LIST R 0.07(3 x .22) 1/ 820k 1/4W ...
Page 10
L4981A - L4981B Figure 10: Reference Voltage vs. Source Refer- ence Current Figure 12: Reference Voltage vs. Junction Tem- perature Figure 14: Gate Driver Rise and Fall Time 10/17 Figure 11: Reference Voltage vs. Supply Voltage Figure 13: Switching Frequency ...
Page 11
Figure 16: Programmable Under Voltage Lock- out Thresholds R22 = R23 6.8 R23 (Kohm) Table 1: Programmable Under Voltage Lockout Thresholds 11V 12V 13V 14V 14.5V 15V Figure 18: Oscillator Diagram Figure 17: Modulation Frequency Normalized in ...
Page 12
L4981A - L4981B Figure 19: 200W Evaluation Board Circuit. T= primary: 75 turns of litz wire AWG (0.2mm) secondary: 8 turns of # 27AWG (0.15mm) core: B1ET3411A THOMSON - CSF gap: 1.4mm for a total primary inductance ...
Page 13
Figure 20: P.C. Board and Component Layout of Evaluation Board Circuit (1:1 scale). L4981A - L4981B 13/17 ...
Page 14
L4981A - L4981B The evaluation board has been designed using: a faster not dissipative start-up circuit, a diode (D2) to speed-up the MOS start-off time and (even if a single resistor can be used) an external divider to improve the ...
Page 15
SO20 PACKAGE MECHANICAL DATA DIM. MIN. TYP. A 2.35 A1 0.1 B 0.33 C 0.23 D 12.6 E 7 0. MAX. MIN. 2.65 0.093 0.3 0.004 0.51 ...
Page 16
L4981A - L4981B DIP20 PACKAGE MECHANICAL DATA DIM. MIN. TYP. a1 0.254 B 1.39 b 0. 2.54 e3 22. 16/17 mm MAX. MIN. 0.010 1.65 0.055 25.4 8.5 7.1 3.93 3.3 ...
Page 17
... STMicroelectronics. Specification mentioned in this publication are subject to change without notice. This publication supersedes and replaces all information previously supplied. STMicroelectronics products are not authorized for use as critical components in life support devices or systems without express written approval of STMicroelectronics. The ST logo is a registered trademark of STMicroelectronics 1998 STMicroelectronics – ...