KA3511 Fairchild Semiconductor, KA3511 Datasheet
KA3511
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KA3511 Summary of contents
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... PG (Power good signal generator) section Power good signal generator is to monitor the voltage level of power supply for safe operation of a microprocessor. KA3511 requires few external components to accomplish a complete housekeeping circuits for SMPS. The KA3511 is available in a 22-pin dual in-line package. November 2,1999 ...
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... ORDERING INFORMATION Device Package KA3511 22 DIP FEATURES • Complete PWM control and house keeping circuitry • Few external components • Precision voltage reference trimmed to 2% • Dual output for push-pull operation • Each output TR for 200mA sink current • Variable duty cycle by dead time control • ...
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PIN DESCRIPTION Pin No. Name I Supply voltage CC 2 COMP O E/A output 3 E/A(-) I E/A (-) input 4 E/A(+) I E/A (+) input 5 TREM – Remote on/off delay 6 REM I Remote ...
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Pin No. Name 1 V Supply voltage. Operating range is 14V~30V COMP Error amplifier output connected to non-inverting input of pulse width modulator comparator. 3 E/A(-) Error amplifier inverting input. Its reference voltage is always ...
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ABSOLUTE MAXIMUM RATINGS Characteristic Supply voltage Collector output voltage Collector output current Power dissipation Operating temperature Storage temperature TEMPERATURE CHARACTERISTICS Characteristic Temperature coefficient of Vref (-25 °C<Ta<85°C) Symbol Value ...
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ELECTRICAL CHARACTERISTICS (V Characteristic REFERENCE SECTION Reference output voltage Line regulation Load regulation Temperature coefficient of Vref Short-circuit output current OSCILLATOR SECTION Oscillation frequency Frequency change with (1) temperature DEAD TIME CONTROL SECTION Input bias current Maximum duty voltage ...
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ELECTRICAL CHARACTERISTICS (continued) Characteristic Over voltage protection for 5V Over voltage protection for 12V Input threshold voltage for PT Under voltage protection for 3.3V Under voltage protection for 5V Under voltage protection for 12V Charging current for UVP delay ...
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... BLOCK DESCRIPTION & APPLICATION INFORMATIONS 6.1 OSCILLATOR BLOCK The KA3511 is a fixed-frequency pulse width modulation control circuit. An internal-linear sawtooth oscillator is frequency-programmable by two external components, R quency is determined by Figure 2. Oscillator Frequency vs. Timing Resistance 6.2 PWM CONTROL BLOCK Output pulse width modulation is accomplished by comparison of the positive sawtooth waveform across capacitor C to either of two control signals ...
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... The pulse-steering flip-flop directs the modulated pulses to each of the two output transistors always for push-pull operation. The output frequency is equal to half that of the oscillator. The KA3511 has an internal 5.0V reference capable of sourcing up to 10mA of load current for external bias circuits. The reference has an internal accuracy of ±2% with typical thermal drift of less than 50mV over an operating temperature range of -25° ...
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DEADTIME CONTROL for SOFT-START Deadtime control for soft-start makes a power supply output rising time (Typ. 15ms) to reduce out- put ringing voltage for 3.3V, 5V, and 12V. If output rising time is too fast, output ringing voltage reaches ...
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So Output Duty Ratio will change from the minimum duty ratio to the maximum duty ratio. Also, if the remote voltage is high, the deadtime control voltage will keep 3V (=3mA xR2 ( the internal 3mA current source ...
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OVP BLOCK OVP function is simply realized by connecting Pin13, Pin14, Pin15 to each secondary output. R1 are internal resistors of the IC. Each OVP level is determined by resistor ratio and the typical ...
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... UVP BLOCK The KA3511 has UVP functions for +3.3V, +5V, +12V Outputs. The block is made up of three input comparators. Each UVP level is determined by resistor ratio and the typical values are 2.3V/4V/ 10V. UVP Detecting voltage for +3.3V V +3.3V UVP 1 UVP Detecting voltage for +5V V +5V UVP 2 UVP Detecting voltage for +12V ...
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REMOTE ON/OFF & DELAY BLOCK Figure 9. Remote ON/OFF Delay Block Remote ON/OFF section is controlled by a microprocessor high signal is supplied to the remote ON/OFF input (Pin6), the output of COMP6 becomes high status. The ...
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... High High Low There is a R-S F/F (Latch) circuit for shutdown operation in the KA3511. R-S F/F (Latch) is con- trolled by OVP, UVP, and some delayed remote ON/OFF signal. If any output of OVP or UVP is High, SET signal of R-S F/F is high status and it produces PWM “High” and main power is turned off. When remote signal is high, its delayed output signal is sup- plied to RESET port of R-S F/F and it produces SET low ...
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POWER GOOD SIGNAL GENERATOR Power good signal generator curcuits generate “ON & OFF” signal depending on the status of out- put voltage to prevent the malfunctions of following systems like microprocessor and etc. from unstable outputs at power on ...
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... Noise_Margin_of_T = V10(max) – Vth(L) = 2.9V – 0. ABOUT TEST METHOD You can verify the KA3511 with a SMPS set. But you should pay attention to the device damage problem by increasing V . You should remove the sub-board after +5Vsb drops to 0V and V CC KA3511 is grounded and then fan stops under the Remote Low. ...
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... HOUSE KEEPING CIRCUIT Using the KA3511 requires few external components to accomplish a complete housekeeping cir- cuits for SMPS. 18 Rev C, November 1999 ...
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TYPICAL CHARACTERISTICS 19 Rev C, November 1999 ...
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Rev C, November 1999 ...
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Rev C, November 1999 ...
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Rev C, November 1999 ...
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PACKAGE DIMENSION 9.14 0.20 0.360 0.008 1 11 10.16 0.400 22-DIP-400 22 12 3.81 0.20 0.150 0.008 5.08 MAX 0.200 23 0.51 MIN 0.020 3.40 0.30 0.134 0.012 Rev C, November 1999 ...
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EXPERIMENTAL RESULT Figure 12. Rising Time of +5Vdc Output Voltage Figure 13. PG Signal Delay Time 24 Rev C, November 1999 ...
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Figure 14. Power Down Warning Figure 15. No Load Protection 25 Rev C, November 1999 ...
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Figure 16. Vcc, +5Vdc Output vs. PG Signal (High) Figure 16. Vcc, +5Vdc Output vs. PG Signal (Low) 26 Rev C, November 1999 ...
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APPLICATION CIRCUIT Reference 1. Power Electronics by Marvin J. Fisher 2. Principles Of Power Electronics by Kassakian AUTHOR: Sang-Tae Im: P-IC Application Team Tel. 82-32-680-1275 Fax. 82-32-680-1317 E-mail. sangtae.im@Fairchildsemi.co. Rev C, November 1999 ...
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... TRADEMARKS The following are registered and unregistered trademarks Fairchild Semiconductor owns or is authorized to use and is not intended exhaustive list of all such trademarks. ACEx™ CoolFET™ CROSSVOLT™ CMOS FACT™ FACT Quiet Series™ ® FAST FASTr™ ...