an8041s Panasonic Corporation of North America, an8041s Datasheet
an8041s
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an8041s Summary of contents
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... Voltage Regulators AN8041S Liquid crystal backlight control IC Overview The AN8041S is an inverter control IC for liquid crystal backlight using PWM method. The output voltage of DC-DC converter and the current of cath- ode-ray tube can be controlled by using two error amplifiers, so that the system is designed easily. ...
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... AN8041S Pin Descriptions Pin No. Symbol Description 1 V Reference voltage output pin REF 2 RT Pin for connecting oscillator timing resistor 3 CT Pin for connecting oscillator timing capacitor 4 DTC Dead-time control pin 5 S.C.P. Pin for connecting the time constant setting capacitor for short-circuit protection ...
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... 200 kHz, dV OUT V 3 200 kHz, dT1 OUT 200 kHz, dT2 OUT AN8041S Min Typ Max Unit 2.483 2.57 2.647 2.8 3.1 3 140 ...
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... AN8041S Electrical Characteristics at V Parameter Bootstrap circuit block Input standby voltage Oscillator block RT terminal voltage Short-circuit protection block Input threshold voltage Input standby voltage Input latch voltage Charge current Comparator threshold voltage On/off control block Threshold voltage Whole device Total consumption current ...
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... The output terminal of the error amplifier 2. Source current : approx. 120 A Sink current : approx Correct the frequency characteristics of the gain and the phase by connecting a resistor and a ca- pacitor between this terminal and IN 2 terminal. AN8041S Description I/O is determined DTC , so that dispersion and ...
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... AN8041S Terminal Equivalent Circuits (continued) Pin No. Equivalent circuit 10 V REF Description IN 2: The inverted input terminal of the error ampli- fier 2. For common-mode input, use in the range The noninverted input terminal of the error am- plifier 2 ...
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... Output duty ratio temperature characteristics 100 50 C) Output duty ratio 100 100 0.2 0.4 C) AN8041S Timing capacitance R 5 000 10 000 Timing capacitance C (pF 100 Ambient temperature ...
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... AN8041S Application Notes (continued) [2] Timing chart 1. PWM comparator operation waveform Off terminal voltage Internal reference voltage (V Power supply Triangular wave (CT) on S.C.P. terminal voltage Out terminal waveform 2. Short-ciruit protection operation waveform Internal reference voltage Error amplifier output (FB1) Short-circuit protection comparator threshold level ...
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... In the case of this IC, the output source current of S.C.P. terminal and DTC terminal are set by the timing resistor R externally attached to RT terminal. For this reason, the AN8041S can not be used as a slave IC when multiple T ICs are synchronously operating in parallel. ...
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... AN8041S Application Notes (continued) [3] Function descriptions (continued) 3. Error amplifier 1 block and error amplifier 2 block (continued) V OUT V REF NF1 Error amplifier 1 C NF1 block DC-DC converter output voltage detection Figure 2. Connection method of the error amplifier 1 and 2 The control modes of backlight are described below: ...
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... S.C.P. terminal (pin 5) starts charging with current charged to approximately 0.75 V, the latch circuit is set to fix the totem pole S I CHG S.C.P. comp 1.82 V S.C. Figure 4. Short-circuit protection circuit AN8041S CHG of the oscillator. It becomes approximately V REF S Q Output cut-off Q R Latch 11 ...
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... AN8041S Application Notes (continued) [3] Function descriptions (continued) 6. Remote circuit The IC control function can be turned on or off by the external control. When the voltage of Off terminal (pin 16) is set under approximately 0.8 V, the internal reference voltage falls to stop the IC control function, and decrease the circuit current to a value under 5 A, When the voltage of Off terminal is set at a value higher than approximately 2 ...
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... Out Figure 6. Output block and bootstrap circuit Turn- Off M1 On Figure 7. Bootstrap circuit operation waveform 1 is fixed The capacitor for boost given by the following equation AN8041S OUT SBD CBH V OH Turn-off DS(ON) V ...
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... AN8041S Application Notes (continued) [3] Function descriptions (continued) 8. Output block, bootstrap circuit (continued) 2) N-channel MOSFET (M1) turn-on time: t When the PWM comparator output reverses, the Out terminal (pin 13) is switched over to high-level. The Out terminal voltage V rises toward the CB terminal voltage (sat) ...
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... Error amp FB2 S.C.P. comp Error amp Bootstrap OSC Constant PWM comp. Error amp. 1 S.C.P. comp. Error amp. 2 1.82 V AN8041S SBD SBD 1 SBD Out Out 8 FB1 FB2 11 ...