L2800 Unisonic Technologies, L2800 Datasheet
L2800
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L2800 Summary of contents
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... LINEAR INTEGRATED CIRCUIT SWITCHING REGULATOR CONTROLLER(LOW VOLTAGE) DESCRIPTION The UTC L2800 is a single-channel switching regulator control IC for low voltage applications incorporating a soft start function and short circuit detection function. The device has a low minimum operating voltage of 1.8V and is ideal for the power supply of battery-operated electronic equipment ...
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... UTC L2800 LINEAR INTEGRATED CIRCUIT PIN DESCRIPTION PIN NO. SYMBOL I/O 1 -IN I Error amplifier inverting input pin 2 SCP - Soft start and SCP setting capacitor connection pin 3 VCC - Power supply pin 4 BR/CTL I Output current setting and control pin 5 OUT O Totem-pole type output pin 6 GND ...
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... UTC L2800 LINEAR INTEGRATED CIRCUIT RECOMMENDED OPERATING CONDITIONS PARAMETER Power Supply Voltage Error Amplifier Input Voltage BR/CTL Pin Input Voltage Output Source Current Output Sink Current SCP Pin Capacitance Phase Compensation Capacitance Output Current Setting Resistance Timing Resistance Timing Capacitance Oscillation Frequency ...
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... UTC L2800 LINEAR INTEGRATED CIRCUIT PARAMETER Output Current Setting Pin Voltage Section/Control Section Input Off Condition Input On Condition Pin Current Range Entire Device Stand-by Current Average Supply Current DIAGRAM FB pin voltage Reference input for short circuit detection comparator Idle period setting voltage ...
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... UTC L2800 LINEAR INTEGRATED CIRCUIT TYPICAL CHARACTERISTICS Supply Voltage vs.Supply Current Supply voltage ,Vcc ( V ) Supply Voltage vs.Input Threshold Voltage 1.0 Ta=+25℃ 0.8 0.6 0.4 0 1.0 2.0 3.0 Supply voltage ,Vcc ( V ) High Level Output Vcc=2V 2.0 Ta=+25℃ R 1.6 1.2 0.8 0 -10 -20 -30 High level output current ,I ...
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... UTC L2800 LINEAR INTEGRATED CIRCUIT BR/CTL Pin Current vs. Output Source Current -50 -40 -30 -20 - -0.4 -0.8 -1.2 BR/CTL pin Current ,I BR BR/CTL Pin Current vs. Supply Current 5.0 4.0 3.0 2.0 1 -20 -40 -60 BR/CTL pin current ,I BR Supply Voltage vs. Frequency Variation Ratio -10 - Supply voltage ,Vcc (V) UTC UNISONIC TECHNOLOGIES CO ...
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... Output Pin Voltage and Current Waveforms (Reference Data) ( OUT 2 0 (mA OUT -50 10mV 0 Note:The OFF delay time of VOUT depends on UTC L2800 4 390Ω UTC UNISONIC TECHNOLOGIES CO., LTD. Vcc=2V C =270pF T Ta=+25℃ 100K 1M Oscillation frequency ,fosc (Hz) 200ns 0.4 0.8 1.2 1.6 the characteristics of the external transistor. ...
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... After charging to approximately 0.8V,the output pin(pin 5) is set low and the SCP pin(pin 2) stays low. Once the protection circuit operates, the circuit can be restored by resetting the power supply.(See “HOW TO SET THE TIME CONSTANT FOR SOFT START AND SHORT CIRCUIT DETECTION”) UTC UNISONIC TECHNOLOGIES CO., LTD. UTC L2800 4 BR/CTL SCP pin(pin 2) ...
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... UTC L2800 LINEAR INTEGRATED CIRCUIT (2) CIRCUIT TO PREVENT MALFUNCTION AT LOW INPUT VOLTAGE Transients when powering on or instantaneous glitches in the supply voltage can lead to malfunction of the control IC and cause system damage or failure. The circuit to prevent malfunction at low input voltage detects a low input voltage by comparing the supply voltage to the internal reference voltage. On detection, the circuit fixes the output pin to low ...