L5991 STMicroelectronics, L5991 Datasheet
L5991
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L5991
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L5991 Summary of contents
Page 1
... August 2001 PRIMARY CONTROLLER WITH STANDBY MULTIPOWER BCD TECHNOLOGY ORDERING NUMBERS: L5991/L5991A (DIP16) line or DC-DC power supply applications using a fixed frequency current mode control. Based on a standard current mode PWM control- ler this device includes some features such as programmable soft start, IN/OUT synchronization, ...
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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, Operating Range j T Storage Temperature, Operating Range stg (*) maximum package power dissipation limits must be observed ...
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... COMP sen COMP VSS = 0. 250mA 20mA 12V 200mA 12V 5mA 20V 20V V = 24V CC C L5991 - L5991A (*) C = 1nF; T Min. Typ. Max. Unit 4.925 5.0 5.075 0.4 mV/ C 4.80 5.0 5.130 V 30 150 mA 0.2 0 100 105 kHz 93 100 107 kHz 46 ...
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... I = 2mA ST-BY V Falling comp V Rising comp Master Operation I = 0.8mA SOURCE Vclock = 3.5V Slave Operation Low Level High Level VSYNC = 3. pin14 V = 15V CC Figure 2. L5991 - Quiescent current vs. input voltage (after disable 7.6V and Y= 8.4V for L5991A µ Min. Typ. Max 100 70 1.0 ...
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... Vcc =15V, after turn-on 500KHz RT=13 CT=1nF 1 300KHz 100KHz 0.1 0.01 -50 - Figure 8. Vref vs. junction temperature. Vref [V]) 5.1 5.05 5 4.95 4 -50 -25 L5991 - L5991A and switching frequency Operating current Vcc =15V, after turn-on RT=13.3k , CT=1nF DC=75%, Co=1nF Quiescent current Start-up current Vc=Vcc= Vccon-0.5V, before turn- ...
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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 = Vc = 15V 25° 0.2 0.4 0.6 Isource [A] Figure 13. UVLO Saturation Ipin10 [mA] 50 Vcc < Vccon 40 before turn- 200 400 600 800 Vpin10 [mV] 6/23 Figure 10 ...
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... V15 = 0V 2.5 2 V15 = Vref 1 Figure 20. E/A frequency response. G [dB] 150 100 50 PIN10 = OPEN 1V pulse 0 on PIN13 100 125 150 0.01 0.1 L5991 - L5991A Rt= 4.5Kohm 1nF Vcc = 15V, V15 100 125 Tj (°C) V15 = 0V V15 = Vref Rt = 4.5Kohm 1nF 100 Duty Cycle [%] 1 10 100 ...
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... T2 T1 still higher than 3.5V). In fig. 22, some practical examples of synchroniz- ing the L5991 are given. Since the device automatically diminishes its op- are inter- erating frequency under light load conditions reasonable to suppose that synchronization will refer to normal operation and not to standby. ...
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... limitation on the maximum duty cycle is re- quired (i.e. D ing. An internal pull-up (see fig. 24) holds the volt- age above 3V. Should the pin pick up noise (e.g. L5991 - L5991A SYNC 600 A CLK D97IN729A ...
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... VFB (pin 5). Compensation networks to- wards ground are not possible since the L5991 E voltage mode amplifier (low output im- pedance). See application ideas for some exam- ple of compensation techniques. ...
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... Besides, no current flows when the gate voltage is 13V, steady state. Under UVLO conditions an internal circuit (shown SHORT T hic L5991 - L5991A + R g only. g ment. Rg' V ...
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... The peculiarity of this circuit is its ability to mantain the same sink capability (typically, 20mA @ 1V) from the start-up threshold. CC When the threshold is exceeded and the L5991 starts operating pulled high (refer to fig. REFOK 28) and the circuit is disabled then possible to omit the "bleeder" resistor ...
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... STANDBY signal goes low the N-channel FET 11 is turned off and the pin becomes floating D97IN498 ISEN OUT DRIVER - R 10V 4 VREF STANDBY ST-BY LEVEL SHIFT RCT L5991 - L5991A (in order to get T , sets the operating frequency of the fact, as long osc is charged through R and V10 · V10 STANDBY ...
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... V and 4V appropriate traces widths and, in case of high voltages, compliance with isolation distances are the major issues. The L5991 eases this task by putting two pins at disposal for separate current returns of bias (SGND) and switch drive currents (PGND) The matter is complex and only few im- portant points will be here reminded ...
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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 38. Bipolar transistor driver. L5991 SGND VREF ISEN R A OPTIONAL D97IN751A ISOLATION BOUNDARY OUT ISEN 13 11 SGND V IN 2.2M 33K STD1NB50 REF 4 L5991 47K 12 11 D97IN762B OUT ISEN 13 L5991 11 PGND D97IN763 L5991 - L5991A R SENSE V IN D97IN761 T SELF-SUPPLY WINDING V IN 17/23 ...
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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 Error Amp compensation circuit for stabilizing current-mode boost and flyback topologies operating with continuous inductor current. ...
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... DC OUT L5991 11 PGND SGND Figure 46. Voltage mode operation Figure 44. Device shutdown on overcurrent L5991 11 PGND SGND D97IN755A ISEN SENSE DC 3 10K L5991 COMP SGND ISEN D97IN758A L5991 - L5991A R START DIS L5991 2.2K SGND PGND D98IN905 2 max VREF R SENSE DIS ISEN SENSE OPTIONAL D97IN756A R· ...
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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 L5991 12 11 PGND D97IN753A ...
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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 0.010 0.787 0.335 0.100 0.700 0.280 0.201 0.130 0.050 L5991 - L5991A OUTLINE AND DIP16 21/23 ...
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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 1.27 e3 8.89 F (1) 3.8 4 0.150 G 4.6 5.3 0.181 L 0.4 1.27 0.016 M 0.62 8˚(max.) S (1) D and F do not include mold flash or protrusions ...
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