S-8540 SII [Seiko Instruments Inc], S-8540 Datasheet
S-8540
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S-8540 Summary of contents
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... Main or sub Power supplies for notebook computers and peripheral equipment. Package Package Name 8-Pin MSOP The S-8540/8541 Series is a family of CMOS step- down switching regulator controllers with PWM control (S-8540 Series) and PWM/PFM switchover control (S- 8541 Series). These devices consist of a reference ...
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... STEP-DOWN, 600 kHz PWM CONTROL or PWM/PFM SWITCHABLE SWITCHING REGULATOR CONTROLLER S-8540/8541 Series Block Diagrams types (fixed output voltage) Pch Pow er MOS FET types (feed back) Pch Power MOS FET for IC VIN T riangu lar wave ...
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... Product Name Structure • The control types, product types, and output voltage for the S-8540/8541 series can be selected at the user’s request. Please refer to the “1. Product name” for the definition of the product name and “2. Product Name List” for the full product names. ...
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... Table 1 S-8540XXXFN Series S-8540A15FN-IAAT2G − S-8541A16FN-IGBT2G S-8540A18FN-IADT2G S-8541A18FN-IGDT2G S-8540A25FN-IAKT2G S-8541A25FN-IGKT2G S-8540A33FN-IAST2G S-8541A33FN-IGST2G S-8540A50FN-IBBT2G S-8540B00FN-IMAT2G S-8541B00FN-IMDT2G Table 2 S-8540XXXFN Series S-8540C18FN-ICDT2G S-8541C18FN-IIDT2G S-8540C25FN-ICKT2G S-8541C25FN-IIKT2G − S-8541C32FN-IIRT2G S-8540C33FN-ICST2G S-8541C33FN-IIST2G S-8540D00FN-IMBT2G S-8541D00FN-IMET2G Seiko Instruments Inc. Rev.3.2 _00 S-8541XXXFN Series − − ...
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... All circuit halts (no step-down operation None connected (A, C types Feed back pin (B, D types) 7 VOUT Output voltage pin 8 SENSE Current limit detection pin *1. The NC pin is electrically open. The NC pin can be connected to VIN and VSS. Seiko Instruments Inc. S-8540/8541 Series Pin Description 5 ...
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... STEP-DOWN, 600 kHz PWM CONTROL or PWM/PFM SWITCHABLE SWITCHING REGULATOR CONTROLLER S-8540/8541 Series Absolute Maximum Ratings Item VIN pin voltage CVREF pin voltage ON/OFF pin voltage *1 FB pin voltage VOUT pin voltage SENSE pin voltage EXT pin voltage EXT pin current Power dissipation ...
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... Caution 1. Line regulation and load regulation may change greatly due to GND wiring when the S-8540 series (PWM control), a state in which the duty ratio 0% continues for several clocks may occur when the input voltage is high and the output current is low. In this case, the operation changes to the pseudo PFM mode, but the ripple voltage hardly increases ...
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... Caution 1. Line regulation and load regulation may change greatly due to GND wiring when the S-8540 series (PWM control), a state in which the duty ratio 0% continues for several clocks may occur when the input voltage is high and the output current is low. In this case, the operation changes to the pseudo PFM mode, but the ripple voltage hardly increases ...
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... Figure 5 CVREF ON/OFF VIN VOUT EXT SENSE VSS Figure 6 ON/OFF VOUT FB SENSE VSS A Figure 7 CVREF ON/OFF FB1 VOUT FB SENSE VSS R SENSE Figure 8 Seiko Instruments Inc. S-8540/8541 Series CVREF VIN EXT ...
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... In the S-8540 series the pulse width varies in the range from 0 to 100% according to the load current, yet ripple voltage produced by the switching can easily be removed by a filter since the switching frequency is always constant ...
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... Soft-start function The S-8540/8541 series has a built-in soft-start circuit. This circuit enables the output voltage to rise gradually over the specified soft-start time to suppress the overshooting of the output voltage and the rush current from the power source when the power is switched on or the power-off pin is set to "H" ...
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... STEP-DOWN, 600 kHz PWM CONTROL or PWM/PFM SWITCHABLE SWITCHING REGULATOR CONTROLLER S-8540/8541 Series 3. ON/ OFF pin (shutdown pin) This pin deactivates or activates the step-down operation. When the pin is set to "L", the OFF switching transistor to go off. All the internal circuits stop working, and substantial savings in current consumption are thus achieved ...
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... VSS or VOUT pin. 5. 100% duty cycle The S-8540/8541 series operates up to the maximum duty cycle of 100%. The switching transistor is kept on continuously to supply current to the load, when the input voltage falls below the preset output voltage value. The output voltage in this case is equal to the subtraction of lowering causes by DC resistance of the coil and on resistance of the switching FET from the input voltage ...
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... Selection of Series Products and Associated External Components 1. Selecting a product The S-8540/8541 series is classified into eight types according to the way of control (PWM and PWM/PFM switching), the oscillation frequencies, and output voltage settings (fixed and feed back). Please select the type that suits your needs best by taking the advantage described below into account. ...
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... OUT When the inductance is large in an S-8540/8541 series product, the output voltage may grow unstable in some cases, depending on the conditions of the input voltage, output voltage, and the load current. Perform sufficient evaluation under the actual condition and decide an optimum inductance. ...
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... STEP-DOWN, 600 kHz PWM CONTROL or PWM/PFM SWITCHABLE SWITCHING REGULATOR CONTROLLER S-8540/8541 Series 5. External transistor The S-8540/8541 series can work with an enhancement (Pch) MOS FET or a bipolar (PNP) transistor as an external transistor Enhancement (Pch) MOS FET The EXT pin can directly drive the Pch MOS FET with a gate capacity of approximate 1200 pF. ...
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... VIN EXT V IN Figure 12 0.4 − I EXTL value of the bipolar transistor from the relation, FE which is calculated from the above equation inserted in parallel with resistance R b × 0.7 OSC Seiko Instruments Inc. S-8540/8541 Series , as shown in Figure value differs depending b 17 ...
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... STEP-DOWN, 600 kHz PWM CONTROL or PWM/PFM SWITCHABLE SWITCHING REGULATOR CONTROLLER S-8540/8541 Series Standard Circuits 1. Fixed output voltage (Pch MOS FET One point ground 2. Feed back type (Pch MOS FET One point ground Caution The above connection diagram and constant will not guarantees successful operation. ...
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... IC manufactured by Seiko Instruments Inc. in relation to the method of using the IC in that product, the product specifications, or the destination country. may vary largely according to the grounding method. OUT In this case the operation changes to the pseudo pulse Seiko Instruments Inc. S-8540/8541 Series , C , and SD GND, and the ...
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... VIN T riangular wave oscillation circuit PWM comparator EXT M/PFM switching control C IN circuit start Shu tdo wn circuit ON/OFF V Figure 15 Seiko Instruments Inc the S-8540/8541B00AFN and SEN SE L SENSE + − Phase VOUT 125m V comp ensation circuit − Error amplifier − ...
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... R A and R . When it is not a negligible value with respect A B precision and the waste current are in a trade-off relation. They must be Seiko Instruments Inc. S-8540/8541 Series = 100 pF affected by the precision of the voltage at B max. of the output voltage OUT /R , the less it is affected by the ...
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... STEP-DOWN, 600 kHz PWM CONTROL or PWM/PFM SWITCHABLE SWITCHING REGULATOR CONTROLLER S-8540/8541 Series Typical Characteristics 1. Examples of major parameters characteristics − V (1) I S-8540/8541(300 kHz) SS1 IN 250 85°C 200 25°C 150 100 50 0 2.5 4.0 5 − V (3) f S-8540/8541(300 kHz) OSC IN 360 85°C 340 320 300 Ta=− ...
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... V PWM 600 kHz OUT IN 3.40 =0 3.35 3.30 3.25 3.20 2.5 4.0 5.5 V (V) IN 85°C 7.0 8.5 10.0 (11) V 400 mA 7 8.5 10 (13) V 100 mA 400 mA 7.0 8.5 10.0 Seiko Instruments Inc. S-8540/8541 Series − V 3.3 V PWM/PFM 600 kHz OUT IN 3.40 =0 OUT 100 mA 3.35 3.30 400 mA 3.25 3.20 2.5 4.0 5.5 7.0 V (V) IN − V 3.3 V PWM/PFM 300 kHz OUT IN 3.40 =0 OUT 100 mA 3.35 3.30 3 ...
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... V IN (2.5 V/div OUT (0.5 V/div ms/div) 24 (2) S-8540A33FN ( (2.5 V/div OUT (1 V/div (4) S-8540C33FN ( (2.5 V/div V/div (6) S-8540A18FN ( (2.5 V/div OUT (0.5 V/div Seiko Instruments Inc. ...
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... V V OUT (0.5 V/div ms/div → 2 Load) ON/OFF OUT (2) S-8540A33FN ( ON/OFF (1 V/div OUT (1 V/div (4) S-8540C33FN ( ON/ V/div OUT (1 V/div (6) S-8540A18FN ( / V/div 1 OUT (0.5 V/div Seiko Instruments Inc ...
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... OUT (2.5 V/div OUT (0.1 V/div) t (0.4 ms/div 3.6→9.0→3 (2) S-8540A33FN ( (2.5 V/div OUT (0.1 V/div) (4) S-8540C33FN ( (2.5 V/div OUT (0.1 V/div) (6) S-8540A18FN ( (2.5 V/div OUT (0.1 V/div) Seiko Instruments Inc. Rev.3.2 _00 : 500 mA) OUT t (0.4 ms/div) ...
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... V/div) t (0.2 ms/div) : 0.1→500 mA, 500→0.1 mA) OUT (2) S-8540A33FN (V 500 0 OUT (0.1 V/div) (4) S-8540C33FN(V 500 mA I OUT 0 OUT (0.1 V/div) (6) S-8540A18FN (V 500 0 OUT (0.1 V/div) Seiko Instruments Inc. S-8540/8541 Series : 4. ms/div ms/div ms/div) 27 ...
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... STEP-DOWN, 600 kHz PWM CONTROL or PWM/PFM SWITCHABLE SWITCHING REGULATOR CONTROLLER S-8540/8541 Series Reference Data This reference data is intended to help you select peripheral components to be externally connected to the IC. Therefore, this information provides recommendations on external components selected with a view to accommodating a wide variety of IC applications. Characteristic data is duly indicated in the table below. ...
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... F, 6.3 V Corporation Nichicon 47 μ F, 10.0 V Corporation Sanyo Electric V =20 V max., V dss Co., Ltd. I =3.0 A max Seiko Instruments Inc. S-8540/8541 Series Size (L × W × Maximum Current 6.5 × × 1.25 0.9 A 7.0 × 7.0 × 3.0 1 0.45 V, 3.0 × 3.1 × 1.3 F 3.6 × 3.0 × 1.2 6.2 × 3.4 × 2.7 =10 V max., 2.9 × ...
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... (mA) OUT 1. 3 S-8540A25FN (2.5 V, 600 kHz, PWM control) 100 =3 (mA) OUT 1. 5 S-8540A18FN (1.8 V, 600 kHz, PWM control) 100 =2 (mA) OUT S-8541A33FN 100 90 80 5 100 1000 1 ...
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... I (mA) OUT 1. 9 S-8540C25FN (2.5 V, 300 kHz, PWM control) 100 =3 (mA) OUT 1. 11 S-8540C18FN (1.8 V, 300 kHz, PWM control) 100 =2 (mA) OUT 1. 8 S-8541C33FN 100 90 80 5 100 1000 1 ...
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... (mA) OUT 2. 5 S-8540C33FN (3.3 V, 600 kHz, PWM control) 100 80 =2 (mA) OUT 2. 7 S-8540C18FN (1.8 V, 300 kHz, PWM control) 100 =2 (mA) OUT 32 ) Characteristics OUT 2. 2 S-8541A33FN 100 5 100 1000 2 ...
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... Use of the information described herein for other purposes and/or reproduction or copying without the express permission of Seiko Instruments Inc. is strictly prohibited. The products described herein cannot be used as part of any device or equipment affecting the human body, such as exercise equipment, medical equipment, security systems, gas equipment, or any apparatus installed in airplanes and other vehicles, without prior written permission of Seiko Instruments Inc ...