s-8541c32fn-iirt2g Seiko Instruments Inc., s-8541c32fn-iirt2g Datasheet
s-8541c32fn-iirt2g
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s-8541c32fn-iirt2g Summary of contents
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... Small package • Lead-free products Applications • Power supplies for PDAs, electric organizers, and portable devices. • Power supplies for audio equipment such as portable CD players and headphone stereos. • Main or sub Power supplies for notebook computers and peripheral equipment. Package Package Name ...
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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 − − S-8541XXXFN Series ...
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... STEP-DOWN, 600 kHz PWM CONTROL or PWM/PFM SWITCHABLE SWITCHING REGULATOR CONTROLLER Rev.3.2 _00 Pin Configuration 8-Pin MSOP TOP view Figure 3 Table 3 Pin No. Pin Name 1 VSS GND pin 2 EXT Connection pin for external transistor 3 VIN IC power supply pin Bypass capacitor connection pin for ...
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... When mounted on board [Mounted board] (1) Board size : (2) Board name : JEDEC STANDARD51-7 Caution The absolute maximum ratings are rated values exceeding which the product could suffer physical damage. These values must therefore not be exceeded under any conditions. (1) When mounted on board 600 500 ...
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... In 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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... In 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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... STEP-DOWN, 600 kHz PWM CONTROL or PWM/PFM SWITCHABLE SWITCHING REGULATOR CONTROLLER Rev.3.2 _00 Measurement Circuits SENSE OUT V ON/OFF FB1 FB2 OUT V ON/OFF R FB2 CVREF ON/OFF VIN VOUT EXT SENSE VSS ...
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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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... The soft-start function of this IC, however, can not suppress rush current to the load completely (Refer to Figure 9) . The rush current is affected by the input voltage and the load. Please evaluate the rush current under the actual test condition. ...
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... OFF pin is configured as shown in Figure 10 . Since pull-up or pull-down is not performed internally, please avoid operating the pin in a floating state. Also, try to refrain from applying a voltage of 0 the pin, lest the current consumption increase. When this leave it coupled to the VIN pin. ...
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... When the voltage difference between Limit VIN pin and VOUT pin is large, the actual current limit value increases since the change with time of the current flowing through the sense resistor becomes large ...
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... Output voltage setting: Two different types are available: fixed output (A and C types) and feed back type (B and D types). Table 8 provides a rough guide for selecting a product depending on the requirements of the application. Choose the product that has the best score ( The set output voltage is fixed (1 ...
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... OUT The capacitor inserted in the input side (C the input current for better efficiency. The C the power supply. It should 100 μ F, although the actual value depends on the impedance of the power source used and load current value. For the output side capacitor (C Resistance) to smoothen the ripple voltage ...
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... The EXT pin can directly drive the Pch MOS FET with a gate capacity of approximate 1200 pF. When a Pch MOS FET is chosen, efficiency will higher than that achieved by a PNP bipolar transistor since the MOS FET switching speed is faster than that of the bipolar transistor and power loss due to the base current is avoided ...
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... STEP-DOWN, 600 kHz PWM CONTROL or PWM/PFM SWITCHABLE SWITCHING REGULATOR CONTROLLER Rev.3.2 _00 5. 2 Bipolar (PNP) transistor Figure 12 shows a circuit diagram using Toshiba Corporation 2SA1213-Y for the bipolar transistor (PNP). Using a bipolar transistor, the driving capacity for increasing the output current is determined by the h value and the R FE The R ...
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... Feed back type (Pch MOS FET One point ground Caution The above connection diagram and constant will not guarantees successful operation. Perform through evaluation using the actual application to set the constant. 18 Power for IC T riangular wave VIN oscillation circuit PWM c omparator − ...
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... Because these largely depend on the inductor, the capacitor and impedance of power supply used, fully check them using an actually mounted model. If the input voltage is high and output current is low, pulses with a low duty ratio may appear, and then the 0% duty ratio continues for several clocks. ...
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... STEP-DOWN, 600 kHz PWM CONTROL or PWM/PFM SWITCHABLE SWITCHING REGULATOR CONTROLLER S-8540/8541 Series Application Circuits 1. External adjustment of output voltage The output voltage can be adjusted or changed in the output voltage setting range (1 adding external resistors (R 8540/8541D00AFN, as shown in Figure 15. thermistor in series One point ground Caution The above connection diagram and constant will not guarantees successful operation ...
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... Set the C FB e.g. When OUT The precision of output voltage (V the FB pin (1 V ± 2.0%), the precision of R voltage Suppose that the FB pin input current is 0 nA, and that the maximum absolute values of the external resistors R and R are and R are R min ...
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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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... STEP-DOWN, 600 kHz PWM CONTROL or PWM/PFM SWITCHABLE SWITCHING REGULATOR CONTROLLER Rev.3.2 _00 − Ta=−40° 25° 2.5 4.0 5.5 V (V) IN − V (10) V 1.8 V PWM/PFM 600 kHz OUT IN 1.85 =0 1.83 OUT 1.81 1.79 100 mA 1.77 1.75 2.5 4 5.5 V (V) IN − V (12) V 3.3 V PWM 600 kHz ...
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... STEP-DOWN, 600 kHz PWM CONTROL or PWM/PFM SWITCHABLE SWITCHING REGULATOR CONTROLLER S-8540/8541 Series 2. Transient Response Characteristics 2. 1 Power- Load) OUT : 0 → 4.95 V) (1) S-8540A33FN ( (2.5 V/div OUT (1 V/div ms/div → 4.95 V) (3) S-8540C33FN ( (2.5 V/div) ...
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... STEP-DOWN, 600 kHz PWM CONTROL or PWM/PFM SWITCHABLE SWITCHING REGULATOR CONTROLLER Rev.3.2 _00 2. 2 Shutdown pin response (V (1) S-8540A33FN (V : 4.95V ON/OFF (1 V/div OUT (1 V/div ms/div) (3) S-8540C33FN ( ON/OFF (1 V/div OUT (1 V/div ms/div) (5) S-8540A18FN ( ...
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... STEP-DOWN, 600 kHz PWM CONTROL or PWM/PFM SWITCHABLE SWITCHING REGULATOR CONTROLLER S-8540/8541 Series 2. 3 Supply Voltage Variation (V (1) S-8540A33FN ( mA) OUT (2.5 V/div OUT (0.1 V/div) t (0.4 ms/div) (3) S-8540C33FN ( mA) OUT (2.5 V/div OUT (0.1 V/div) t (0.4 ms/div) (5) S-8540A18FN ( mA) OUT ...
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... STEP-DOWN, 600 kHz PWM CONTROL or PWM/PFM SWITCHABLE SWITCHING REGULATOR CONTROLLER Rev.3.2 _00 2. 4 Load Variation ( (1) S-8540A33FN ( 500 mA I OUT 0 OUT (0.1 V/div) t (0.2 ms/div) (3) S-8540C33FN 500 mA I OUT 0 OUT (0.1 V/div) t (0.2 ms/div) (5) S-8540A18FN ( 500 ...
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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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... STEP-DOWN, 600 kHz PWM CONTROL or PWM/PFM SWITCHABLE SWITCHING REGULATOR CONTROLLER Rev.3.2 _00 Component Product Name LDR655312T-4R7 Inductor CDRH6D28-220 Diode RB491D Output F920J476MB Capacity (tantalum F931A476MC electrolytic) Transistor CPH6301 (MOS FET) Table 12 External parts function Manufacturer L-Value Resistance TDK 4.7 μ H 0.19 Ω Corporation Sumida 22.0 μ ...
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... STEP-DOWN, 600 kHz PWM CONTROL or PWM/PFM SWITCHABLE SWITCHING REGULATOR CONTROLLER S-8540/8541 Series 1. Efficiency Characteristics : Efficiency (η) − Output current ( S-8540A33FN (3.3 V, 600 kHz, PWM control) 100 =4 (mA) OUT 1. 3 S-8540A25FN (2.5 V, 600 kHz, PWM control) 100 =3 ...
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... STEP-DOWN, 600 kHz PWM CONTROL or PWM/PFM SWITCHABLE SWITCHING REGULATOR CONTROLLER Rev.3.2 _00 1. 7 S-8540C33FN (3.3 V, 300 kHz, PWM control) 100 =4 (mA) OUT 1. 9 S-8540C25FN (2.5 V, 300 kHz, PWM control) 100 =3 (mA) OUT 1. 11 S-8540C18FN (1 ...
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... STEP-DOWN, 600 kHz PWM CONTROL or PWM/PFM SWITCHABLE SWITCHING REGULATOR CONTROLLER S-8540/8541 Series ) − Output Current (I 2. Ripple Voltage (V rip 2. 1 S-8540A33FN (3.3 V, 600 kHz, PWM control) 100 7 (mA) OUT 2. 3 S-8540A18FN (1.8 V, 600 kHz, PWM control) 100 ...
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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 ...