STEVAL-ISA007V1 STMicroelectronics, STEVAL-ISA007V1 Datasheet
STEVAL-ISA007V1
Specifications of STEVAL-ISA007V1
Related parts for STEVAL-ISA007V1
STEVAL-ISA007V1 Summary of contents
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CURRENT-MODE CONTROL PWM SWITCHING FREQUENCY UP TO 1MHz LOW START-UP CURRENT (< 120 A) HIGH-CURRENT OUTPUT DRIVE SUITABLE FOR POWER MOSFET (1A) FULLY LATCHED PWM LOGIC WITH DOU- BLE PULSE SUPPRESSION PROGRAMMABLE DUTY CYCLE 100% AND 50% MAXIMUM DUTY ...
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L5991 - L5991A ABSOLUTE MAXIMUM RATINGS Symbol V Supply Voltage ( Output Peak Pulse Current OUT Analog Inputs & Outputs (6,7) Analog Inputs & Outputs (1,2,3,4,5,15,14, 13, 16) P Power Dissipation @ T tot T Junction Temperature, ...
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ELECTRICAL CHARACTERISTICS (V unless otherwise specified.) Symbol Parameter REFERENCE SECTION V Output Voltage REF Line Regulation Load Regulation T Temperature Stability S Total Variation I Short Circuit Current OS Power Down/UVLO OSCILLATOR SECTION Initial Accuracy Duty Cycle Duty Cycle Accuracy ...
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L5991 - L5991A ELECTRICAL CHARACTERISTICS (continued.) Symbol Parameter OUTPUT SECTION Fall Time Rise Time UVLO Saturation SUPPLY SECTION V Startup voltage CCON V Minimum Operating CCOFF Voltage V UVLO Hysteresis hys I Start Up Current S I Operating Current op ...
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Figure 3. Quiescent current vs. input voltage ref 4.5Koh ° ...
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L5991 - L5991A Figure 9. Vref vs. junction temperature. Vref [V] 5.1 Vcc = 15V 5.05 Iref= 20mA 5 4.95 4.9 -50 - (°C) Figure 11. Output saturation. Vsat = V [ Vcc ...
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Figure 15. Switching frequency vs. tempera- ture. fsw (KHz) 320 Rt= 4.5Kohm 1nF 310 Vcc = 15V, V15=Vref 300 290 280 -50 - (°C) Figure 17. Dead time vs Ct. Dead time [ns] ...
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L5991 - L5991A STANDBY FUNCTION The standby function, optimized for flyback topol- ogy, automatically detects a light load condition for the converter and decreases the oscillator fre- quency on that occurrence. The normal oscillation frequency is automatically resumed when the ...
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Figure 23. Oscillator and synchronization internal schematic REF CLAMP R A RCT ST-BY 16 STANDBY The oscillation frequency can be established with the aid of the diagrams of fig. 14, where ...
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L5991 - L5991A during ESD tests), it can be connected to VREF through a 4.7k resistor. Figure 24. Duty cycle control REF ST- RCT 2 - ...
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Since the system tries restarting each hiccup cy- cle, there is not any latchoff risk. "Hiccup" keeps the system in control in case of short circuits but does not eliminate power com- ponents overstress during pulse-by-pulse limita- tion (from A ...
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L5991 - L5991A in fig.28) holds the pin low in order to ensure that the external MOS cannot be turned on acciden- tally. The peculiarity of this circuit is its ability to mantain the same sink capability (typically, 20mA @ ...
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Figure 30. Disable (Latched). DISABLE SIGNAL DIS 2.5V connecting DC-LIM to VREF (half duty cycle op- tion), Dx will be set approximately at 260 T Figure 31. Half duty cycle ...
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L5991 - L5991A now disconnected and C is charged through R T only. In this way the oscillator frequency (f be lower. Refer to pin 2 description to see how to calculate the timing components. Typical values for V and ...
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APPLICATION IDEAS Here follows a series of ideas/suggestions aimed at Figure 33. Typical application circuit for computer monitors (90W). either improving performance or solving common application problems of L5991 based supplies. L5991 - L5991A 15/23 ...
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L5991 - L5991A Figure 34. Typical application circuit for inkjet printers (40W). 16/23 ...
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Figure 35. Standby thresholds adjustment. Figure 36. Isolated MOSFET Drive & Current Transformer Sensing in 2-switch Topologies. L5991 12 PGND Figure 37. Low consumption start-up. 20V Figure 38. Bipolar transistor driver. L5991 SGND VREF ISEN ...
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L5991 - L5991A Figure 39. Typical E/A compensation networks. From Error Amp compensation circuit for stabilizing any current-mode topology except for boost and flyback converters operating with continuous inductor current. From V ...
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Figure 42. Protection against overvoltage/feedback disconnection (latched) R START DIS L5991 SGND PGND D97IN754 Figure 43 Protection against overvoltage/feed- back disconnection (not latched) R START V CC VREF 4 8 L5991 ...
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L5991 - L5991A Figure 47. Device shutdown on mains undervoltage 80÷400V Figure 48. Synchronization to flyback pulses (for monitors). 20/ VREF 4 4.7K 3 5.1 R2 10K SGND D97IN750B SYNC L5991 5.1V SGND ...
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DIM. MIN. TYP. MAX. MIN. a1 0.51 0.020 B 0.77 1.65 0.030 b 0 8.5 e 2.54 e3 17.78 F 7.1 I 5.1 L 3.3 Z 1.27 inch MECHANICAL DATA TYP. MAX. 0.065 0.020 ...
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L5991 - L5991A mm DIM. MIN. TYP. MAX. MIN. A 1.75 a1 0.1 0.25 0.004 a2 1.6 b 0.35 0.46 0.014 b1 0.19 0.25 0.007 C 0.5 c1 45˚ (typ.) D (1) 9.8 10 0.386 E 5.8 6.2 0.228 e ...
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