S-8328B33MC-EWN-T2 Seiko, S-8328B33MC-EWN-T2 Datasheet
S-8328B33MC-EWN-T2
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S-8328B33MC-EWN-T2 Summary of contents
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... Contents Features .............................................................. 1 Applications ......................................................... 1 Block Diagram ..................................................... 1 Selection Guide ................................................... 2 Pin Assignment ................................................... 3 Absolute Maximum Ratings ................................. 3 Electrical Characteristics ..................................... 4 Test Circuits ........................................................ 9 Operation............................................................. 9 External Parts Selection for DC-DC Converter .... 12 Standard Circuits ................................................. 16 Precautions ......................................................... 18 Application Circuits .............................................. 19 Dimensions.......................................................... 24 Markings.............................................................. 24 Taping ................................................................ 25 Temperature Characteristics ............................... 28 Characteristics for the Power Voltage.................. 30 Ripple characteristics .......................................... 31 Transient Responses........................................... 32 Operation Start Voltage and Operation Holding Voltage Characteristics for Output Current ...
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... A step-up switching regulator is constructed by externally connecting only a coil, a capacitor and a diode to the S-8324 Series. This feature, along with its small package and low current consumption, makes the S-8324 Series ideal for the power supply of portable equipment ...
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... S-8328BXXMC voltage(v) Series 2.0 — 2.5 S-8328B25MC-EWF-T2 S-8328B25MA-EWF-T2 S-8328B25UA-EWF-T2 2.7 S-8328B28MC-EWH-T2 S-8328B28MA-EWH-T2 S-8328B28UA-EWH-T2 3.0 S-8328B30MC-EWK-T2 S-8328B30MA-EWK-T2 S-8328B30UA-EWK-T2 3.3 S-8328B33MC-EWN-T2 S-8328B33MA-EWN-T2 S-8328B33UA-EWN-T2 3.6 S-8328B36MC-EWQ-T2 3.8 S-8328B38MC-EWS-T2 5.0 S-8328B50MC-EXE-T2 S-8328B50MA-EXE-T2 S-8328B50UA-EXE-T2 5.2 S-8328B52MC-EXG-T2 Consult our sales person for products with an output voltage other than specified above. 3. Function List Built In power with external ...
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... S-8328 Series) Absolute Maximum Ratings Note: A protect circuit for static electricity is built into this IC chip. However, prevent a charge of static electricity which exceeds the capacity of the protect circuit. Parameter VOUT pin voltage ON/OFF pin voltage CONT pin voltage CONT pin current ...
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... Soft start time T SS Efficiency EFFI External parts used: -Coil: CD54 (100 H) of Sumida Electric Co., Ltd. -Diode: MA720 (schottky type) of Matsushita Electronic Components Co., Ltd. -Capacitor: F93 (16V tantalum type) of Nichicon Corporation) Applied V =output voltage 0.6, I =output voltage/250 IN OUT The shutdown pin is connected to V ...
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... Measured waveform at CONT pin V = output voltage - 0. load S-8324X50XX S-8324X33XX S-8324X30XX S-8324X27XX S-8324X25XX S-8324X20XX separate product. =0.8V recommended to stabilize the output voltage and oscilation frequency. DD Seiko Instruments Inc. S-8324/8328 Series (Unless otherwise specified: Ta=25 C) Min. Typ. Max. Unit Test circuit 4.880 5.000 5.120 3.221 3 ...
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... MA720 (schottky type) of Matsushita Electronic Components Co., Ltd. -Capacitor: F93 (16V tantalum type) of Nichicon Corporation) Applied V =output voltage 0.6, I =output voltage/250 IN OUT Note 1 : The output voltage specified above is the typical value. 6 Conditions S-8324C30MA S-8324C27MA S-8324C25MA I =1mA OUT No external parts, voltage applied to V ...
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... T SS Efficiency EFFI External parts used: -Coil: CD54 ( Sumida Electric Co., Ltd. -Diode: MA720 (schottky type) of Matsushita Electronic Components Co., Ltd. -Capacitor: F93 (16V tantalum type) of Nichicon Corporation) -Transistor: 2SD1628G of Sanyo Electronics -Base resistor (Rb): 1.0K -Base capacitor (Cb): 2200pF (ceramic) Applied V =output voltage 0.6, I ...
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... V = output voltage - 0. load S-8328X50XX S-8328X33XX S-8328X30XX S-8328X27XX S-8328X25XX S-8328X20XX /V separate product. OUT =0.8V recommended to stabilize the output voltage and oscilation frequency. DD Seiko Instruments Inc. (Unless otherwise specified: Ta=25 C) Min. Typ. Max. Unit Test circuit 4.880 5.000 5.120 3.221 3.300 3.379 2.928 3 ...
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... In conventional fixed-duty type PFM DC/DC converters, pulses are skipped at low output load current, causing fluctuation in ripple frequency of the output voltage, with the result of increase in ripple voltage. The S-8324/8328 series operates with the PWM control which changes the pulse width duty from 15% to 83% in the region of large output load current. ...
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... Do NOT use the shutdown pin in floating state because it has a structure shown in Figure 4 and is not pulled up or pulled down internally. Do NOT apply voltage of between 0.3 V and 0. the shutdown pin because applying such voltage increases the current consumption. If the shutdown pin is not used, connect The shutdown pin doesn’ ...
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... L and is not transmitted energy of the capacitor ( consumed result, the pin voltage of C OUT M1 is turned When M1 is turned OFF, the energy stored transmitted through the diode voltage of C rises drastically. V OUT OUT ...
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... Therefore to reduce the ripple voltage important that the capacitor connected to the output pin has a large capacity and a small ESR. External Parts Selection for DC-DC Converter The relationship between majorcharacteristics of the step-up circuit and characteristics parameters of the external parts are shown in Figure 6. ...
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... Further increasing L decreases efficiency due to the loss of the DC resistance of the coil 220 H inductor for S-8324 and 22 to 100 H inductor for S-8328 are recommended. Choose a value for L by refering to the reference data because the maximum output current is due to the input voltage in an actual case. ...
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... FE A small Rb increases output current, however, the efficiency decreases. The current flows pulsating and there is voltage drop due to wiring resistance in an actual circuit, therefore optimum Rb value should be determined by experiment. A speed-up capacitor connected in parallel with Rb resistance as shown in Figure 9 decreases the switching loss and improves the efficiency ...
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... S-8328E20, the circuit operates only when the MOS FET has the threshold voltage lower than 2.0V. 5. Others (S-8324D and S-8328E only) The S-8324D and S-8328E are applicable to the following uses because the power pin for IC chip and Vout pin for output voltage are separated: When changing the output voltage with an external resistance ...
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... SMALL PACKAGE PWM/PFM CONTROL STEP-UP SWITCHING REGULATOR S-8324/8328 Series Standard Circuits (1) S-8324AXXMC OFF (2) S-8328BXXMC 2200pF OFF (3) S-8324AXXMA S-8324AXXUA S-8324CXXMA CONT PWM + control circuit IN Soft start circuit Figure 10 SD PWM EXT + control circuit Soft start circuit ...
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... SMALL PACKAGE PWM/PFM CONTROL STEP-UP SWITCHING REGULATOR (4) S-8328BXXMA S-8328BXXUA L 2200pF (5) S-8324DXXMC (Output voltage adjustment circuit with external resistors) L CONT (6) S-8328EXXMC (Output voltage adjustment circuit with external resistors) L 2200pF EXT - VREF PWM EXT + control ...
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... Mount external capacitors, a diode, and a coil as near as possible to the IC. Ripple voltage and spike noise occur in switching regulators. Because they largely depend on the coil and the capacitor used, check them using an actually mounted model. Seiko Instruments shall not be responsible for any patent infringement by products including S-8324/8328 Series in connection with the method of using S-8324/8328 Series in such products, the specification of such products, or the country of destination thereof ...
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... SMALL PACKAGE PWM/PFM CONTROL STEP-UP SWITCHING REGULATOR Application Circuits 1. Backup Circuit Reduces the backup battery voltage from 1.5 V (from 2 cells to 1 cell 1.5V 2. 5V/Backup Change The S-8324A/8328B is provided with a power OFF function, where V allows the backup voltage of the microcomputer to be supplied with low current consumption. ...
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... SMALL PACKAGE PWM/PFM CONTROL STEP-UP SWITCHING REGULATOR S-8324/8328 Series 4. PDA/Digital Camera Power Supply The following are a circuit example and its characteristics showing a 3-V system drive (3V/200mA) powered by 4 secondary Nicd batteries (3.6 to 4.8V), 2 lithium-ion batteries (4.8 to 8.8V alkaline-manganese batteries (3.6 to 6.0V (a) Output Current - Output Voltage 3 ...
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... Voltage Inverting Type DC/DC Converter The Start circuit is not needed because the power is supplied from V When and - 5 V, use the S-8324D20MC, the S-8324D30MC and the S-8324D50MC respectively. Always CC connect V to GND without attaching R OUT Set more and R b the efficiency to be improved ...
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... Set more and efficiency to be improved. On the other hand, the switching loss of the Tr becomes large and consequently the efficiency will be worsened. Select R to ensure high efficiency under operating conditions LCD Power Supply (Standard circuit (6)) The following are an application power supply circuit (30V/5mA) for intermidiate and large size LCD, and its characteristics when 3V (3V± ...
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... Output Voltage V (V) OUT 0.01 0.1 Output Current I 8. Flash Memory Power Supply The following are a circuit example and its characteristics for Flash Memory, 16 Mbit (5V/120mA single lithium battery (2 4.4 V). L CD54/ 2SD1628G (a)Output Current - Output Voltage 5 ...
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... SMALL PACKAGE PWM/PFM CONTROL STEP-UP SWITCHING REGULATOR S-8324/8328 Series n Dimentions (1) SOT-23-5 2.9 (3.1 max.) 1.6 ± 0.4 0.1 ± 1.1 0 min. ± ± 0.95 0.1 0.95 0.1 ± 1.9 0.2 (3) SOT-89-3 4.5 1.6 ± 2.5 0.2 0.8 min. ± 1.5 0.1 ± 0.4 0.1 0.45 (0.4) 2.5 45 (0.4) n Markings (2) SOT-23-3 (1) SOT-23-5 … ‚ ƒ • „ … • to ‚ Product No. (abbreviation) „ to … Lot No. ...
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... SMALL PACKAGE PWM/PFM CONTROL STEP-UP SWITCHING REGULATOR Taping 1. Tape Specification 1-1 SOT-23-5 1-2 SOT-23-3 1.5 (3.1) 0.3 ± 2.85 0.2 +0.2 +0.1 2.0±0.05 1 less 3.2±0.1 Figure 33 +0.1 1.1±0.1 2.0±0.1 -0.05 4.0±0.1 Feed direction Figure 34 Seiko Instruments Inc. S-8324/8328 Series ± 4.0±0.1(total10 : 40.0 0.2) 1.75±0.1 3.5±0.05 8.0±0.2 3.23±0 less 4.0±0.1 ± ...
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... SMALL PACKAGE PWM/PFM CONTROL STEP-UP SWITCHING REGULATOR S-8324/8328 Series 1-3 SOT-89-3 2. Reel Specifications 2-1 SOT-23-5/SOT-23-3 One reel holds 3000 regulators. 10.5±0.4 4.0±0.1(total10 : 40.0±0.2) +0.1 1.5 -0 2.0±0. less 4.75±0.1 Figure 35 2±0 180 -3 Figure 36 Seiko Instruments Inc. 1.5±0.1 5.65±0.05 4.35±0.1 12±0 ...
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... SMALL PACKAGE PWM/PFM CONTROL STEP-UP SWITCHING REGULATOR 2-2 SOT-89-3 One reel holds 1000 regulators. ± 10.5 0.4 (60 ) ± 2 0.2 ( 180 -3 Figure 37 Seiko Instruments Inc. S-8324/8328 Series 16.5 Max. (dimension of external reel core) (1.5) ± ± 13.0 0.3 (dimension of inner reel core) ± 15.4 1.0 (dimension of inner reel core) ...
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... SMALL PACKAGE PWM/PFM CONTROL STEP-UP SWITCHING REGULATOR S-8324/8328 Series Temperature Characteristics ST1 S-8324 V =3.0V, fosc=50kHz type OUT 1.2 1.0 0.8 V ST1 (V) 0.6 0.4 0.2 0.0 -40 - SS1 S-8324 V =3.0V, fosc=50kHz type OUT SS1 ( -40 - SSS S-8324 V =3.0V, fosc=50kHz type OUT 1.0 0.8 I 0.6 SSS ( A) 0.4 0.2 0.0 -40 ...
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... SMALL PACKAGE PWM/PFM CONTROL STEP-UP SWITCHING REGULATOR MaxDuty - Ta S-8324 V =3.0V, fosc=50kHz type OUT 100 90 80 MaxDuty (%) -40 - S-8324 V =3.0V, fosc=50kHz type OUT 1.0 0.8 0 (V) 0.4 0.2 0.0 -40 - SL2 S-8324 V =3.0V, fosc=50kHz type OUT 1.0 0.8 0.6 V SL2 (V) 0.4 0.2 0.0 -40 - ...
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... SMALL PACKAGE PWM/PFM CONTROL STEP-UP SWITCHING REGULATOR S-8324/8328 Series Characteristics for the Power Voltage SS1 2 OUT S-8324 Ta= =5.0V, fosc=50kHz type OUT SS1 I SS2 (V) OUT osc OUT S-8324 Ta= =5.0V, fosc=50kHz type OUT osc ...
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... SMALL PACKAGE PWM/PFM CONTROL STEP-UP SWITCHING REGULATOR Ripple characteristics S-8324A330 1.LIght Load (I =200 A) OUT Output Voltage (10mV/div) 3V CONT Voltage (1V/div sec/div) 2.Medium Load (I =10mA) OUT Output Voltage (10mV/div) 3V CONT Voltage (1V/div (10 sec/div) S-8328B30 1.LIght Load (I =200 A) OUT Output Voltage ...
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... Output V. (1V/div (1m sec/div) S-8328B30 (Light Load:I =1mA) OUT 2V Input Vol. (1V/div Output V. (1V/div (1m sec/div) 2. Powering ON due to Shutdown pin (Von/off :0V S-8324A30 (Light Load:I =1mA) OUT 3V Input Vol. (1V/div Output V. (1V/div) 0V S-8328B30 (Light Load:I =1mA) OUT 3V Input Vol. (1V/div) ...
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... SMALL PACKAGE PWM/PFM CONTROL STEP-UP SWITCHING REGULATOR 3.Load Fluctuations S-8324A30 (I :100 A 50mA) OUT 50mA Load Current 100 A 3V Output Vol. (50mV/div) t (100 sec/div) S-8328B30 (I :100 A 100mA) OUT 100mA Load Current 100 A 3V Output Vol. (50mV/div) t (100 sec/div) 4.Power Voltage Fluctuations S-8324A30 (V :1 ...
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... SMALL PACKAGE PWM/PFM CONTROL STEP-UP SWITCHING REGULATOR S-8324/8328 Series Operation Start Voltage and Operation Holding Voltage Characteristics for Output Current S-8324A30 1.0 0.8 Input 0.6 V Voltage IN 0.4 0.2 0 Output Current S-8328B30 1.0 0.8 0.6 Input Voltage V IN 0.4 0.2 0 Output Current Input Voltage Characteristics for Input Current S-8324A ...
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... For instance, when V =0. There is no difference between conditions (4) to (6) when the output current is 100 A at stand-by condition. Therefore, choose condition (6). *5) Read the ripple voltage under the operational condition selected above from “Reference data 2 ripple voltage characteristics for output current” ...
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... No. V OUT (10) 3V (11) 3V (12) 3V (13) 3V (14) 5V (15) 5V (16) 5V (17) 5V The efficiency of the external parts are shown below Part Inductor Diode (Schott key) Output capacitor Externaltransistor 36 Table 1 S-8324 Series Model L value D name of L LQH3C 220 H MA720 LQH4N 220 H LQH4N 220 H CD54 ...
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... LQH4N 2V LQH3C The S-8324/28 Series improves efficiency by switching PWM control to PFM control automatically when the output current is decreased. The reference data 1 shows the output current data switching PWM control to PFM control. Reference Data 1 (a) output voltage characteristics for output current, (b) efficiency characteristics for output current and (C) PWM/PFM switching characteristics under (1) to (17) conditions shown in Table 1 and 2 are shown below ...
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... SMALL PACKAGE PWM/PFM CONTROL STEP-UP SWITCHING REGULATOR S-8324/8328 Series (2) S-8324A20 (LQH4N : 220 H) (a) Outpur Current - Output Voltage 2.05 2.03 Output Voltage 2.01 V OUT (V) 1.99 1.97 1.95 0.01 0.1 1. Output Current (c) PWM/PFM Switching 2.0 PFM 1.5 Input Voltage V 1.0 IN (V) 0.5 0.0 0.1 Output Current (3) S-8324A30 (LQH4N : 220 H) (a) Outpur Current - Output Voltage 3.05 3.03 Output Voltage 3 ...
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... SMALL PACKAGE PWM/PFM CONTROL STEP-UP SWITCHING REGULATOR (4) S-8324A30 (CD54 : 47 H) (a) Outpur Current - Output Voltage 3.05 3.03 3.01 Output Voltage V OUT (V) 2.99 2.97 2.95 0.01 0.1 1. Output Current (c) PWM/PFM Switching 3.0 PFM 2.5 2.0 Input Voltage V IN 1.5 (V) 1.0 0.5 0.0 0.1 1. Output Current (5) S-8324A30 (CD54 : 100 H) (a) Outpur Current - Output Voltage 3.05 3.03 3.01 Output Voltage V OUT (V) 2.99 2.97 2.95 0.01 0.1 1. ...
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... SMALL PACKAGE PWM/PFM CONTROL STEP-UP SWITCHING REGULATOR S-8324/8328 Series (6) S-8324A30 (CD54 : 220 H) (a) Outpur Current - Output Voltage 3.05 3.03 3.01 Output Voltage V OUT (V) 2.99 2.97 2.95 0.01 0.1 1. Output Current (c) PWM/PFM Switching 3.0 PFM 2.5 2.0 Input Voltage 1 (V) 1.0 0.5 0.0 0.1 Output Current (7) S-8324A50 (CD54 : 47 H) (a) Outpur Current - Output Voltage 5.10 5.06 Output Voltage 5.02 V OUT (V) 4 ...
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... SMALL PACKAGE PWM/PFM CONTROL STEP-UP SWITCHING REGULATOR (8) S-8324A50 (CD54 : 100 H) (a) Outpur Current - Output Voltage 5.10 5.06 Output Voltage 5.02 V OUT (V) 4.98 4.94 4.90 0.01 0.1 1. Output Current (c) PWM/PFM Switching 5.0 4.5 PFM 4.0 3.5 3.0 Input Voltage V 2.5 IN (V) 2.0 1.5 1.0 0.5 0.0 0.1 1. Output Current (9) S-8324A50 (CD54 : 220 H) (a) Outpur Current - Output Voltage 5.10 5.06 Output Voltage 5.02 V OUT (V) 4 ...
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... SMALL PACKAGE PWM/PFM CONTROL STEP-UP SWITCHING REGULATOR S-8324/8328 Series (10) S-8328B30 (CD105 : 22 H, Rb=300 (a) Outpur Current - Output Voltage 3.05 3.03 Output Voltage 3.01 V OUT (V) 2.99 2.97 2.95 0.01 0.1 1. Output Current (c) PWM/PFM Switching 3.0 PFM 2.5 2.0 Input Voltage V IN 1.5 (V) 1.0 0.5 0.0 0.1 1. Output Current (11) S-8328B30 (CD105 : 22 H, Rb=1k (a) Outpur Current - Output Voltage 3.05 3.03 3.01 Output Voltage ...
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... SMALL PACKAGE PWM/PFM CONTROL STEP-UP SWITCHING REGULATOR (12) S-8328B30 (CD54 : 47 H, Rb=1k , Cb=0.0022 F) (a) Outpur Current - Output Voltage 3.05 3.03 3.01 Output Voltage V OUT (V) 2.99 2.97 2.95 0.01 0.1 1. Output Current (c) PWM/PFM Switching 3.0 PFM 2.5 2.0 Input Voltage V IN 1.5 (V) 1.0 0.5 0.0 0.1 1. Output Current (13) S-8328B30 (D75C : 47 H, Rb=1k , Cb=0.0022 F) (a) Outpur Current - Output Voltage 3.05 3.03 Output Voltage 3 ...
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... SMALL PACKAGE PWM/PFM CONTROL STEP-UP SWITCHING REGULATOR S-8324/8328 Series (14) S-8328B50 (CD105 : 22 H, Rb=300 (a) Outpur Current - Output Voltage 5.10 5.06 5.02 Output Voltage V OUT (V) 4.98 4.94 4.90 0.01 0.1 1. Output Current (c) PWM/PFM Switching 5.0 4.5 PFM 4.0 3.5 Input Voltage 3 2.5 (V) 2.0 1.5 1.0 0.5 0.0 0.1 1. Output Current (12) S-8328B50 (CD105 : 22 H, Rb=1k (a) utpur Current - Output Voltage 5.10 5.06 Output Voltage 5 ...
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... SMALL PACKAGE PWM/PFM CONTROL STEP-UP SWITCHING REGULATOR (16) S-8328B50 (CD54 : 47 H, Rb=1k (a) Outpur Current - Output Voltage 5.10 5.06 5.02 Output Voltage V OUT (V) 4.98 4.94 4.90 0.01 0.1 1. Output Current (c) PWM/PFM Switching 5.0 4.5 PFM 4.0 3.5 Input Voltage 3 2.5 (V) 2.0 1.5 1.0 0.5 0.0 0.1 1. Output Current (17) S-8328B50 (D75C : 47 H, Rb=1k (a) Outpur Current - Output Voltage 5.10 5.06 Output Voltage 5.02 V OUT (V) 4.98 4.94 4.90 0.01 0.1 1. Output Current (c) PWM/PFM Switching 5 ...
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... SMALL PACKAGE PWM/PFM CONTROL STEP-UP SWITCHING REGULATOR S-8324/8328 Series Reference data 2 Ripple voltage characteristics data are shown below. (1) S-8324A20 (LQH3C : 220 H, C =22 F) OUT Similar to (2) (3) S-8324A30 (LQH4N : 220 H, C =22 F) OUT Similar to (6) (4) S-8324A30 (CD54 : =22 F) OUT 100 in V =0.9V ...
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... SMALL PACKAGE PWM/PFM CONTROL STEP-UP SWITCHING REGULATOR (8) S-8324A30 (CD54 : 220 H, C =22 F) OUT 100 VIN=0.9V 80 VIN=1.8V VIN=2.4V 60 Ripple Voltage Vr(mV 0.1 1. Output Current (10) (11) S-8328B30 (CD105 : = OUT 100 VIN=0.9V 80 VIN=1.8V VIN=2.4V 60 Ripple Voltage Vr(mV 0.1 1. Output Current (12) S-8328B30 ...
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... VREF is converted to an output voltage VOUT level (Vref = VREF x (R1 + R2) VOUT increases to close to VIN immediately after the power is switched on, as the current is supplied from VIN to VOUT via L and SD of the measurement circuit. ...
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... L 2200pF EXT ON/OFF Waveforms 2V Input Voltage (1V/div Output Voltage (1V/div) 0V <Remarks> FAQ No.: 11S8323013 SD VREF (R1 R2)/R2 PWM Control Circuit Soft-Start Circuit VOUT Vref t (1msec/div VOUT OUT Vref OUT V SS ...
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... VDD S-8327/8E CIN VIN EXT Tr1 The output voltage can be adjusted by adding Tr2 and RE to the output-voltage regulation circuit in the above circuit diagram. If the internal resistance of VOUT, etc. is not taken into account, output voltage VEE can be represented by the following equation ...
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... VEEmin. The procedure for this should comply with FAQ No. 11S8323007. (In particular, use of the software is recommended.) 2. Then, set an RE that will allow the output voltage to exceed VEEmax. when Tr2 comes on. Such a value can be found using the following equation, where OUTmin. is the minimum deviation value (OUTmin ...
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... Category 2: 4. Switching Regulators Cal No.: S-8323/24/27/28 Related Documents: Question: What remedial action will be taken against the phenomenon observed in an output-voltage regulation circuit, in which a boosting pulse is delivered momentarily and a rush current flows immediately after the power is switched on? Answer: Coil current 150uH Q1 • { ...
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... Q2 at the moment the Vdd switch (Q1) goes off, so that VOUT will be made equal to the VDD level via RA, as shown in Figure 2. (Normally, RA and RB are cut off in order to eliminate the reactive current generated when the power is switched off.) ...
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... VIN × (2 (The above equation can be derived from Formulas (4) and (17) in the Data Book and Duty = ton x fosc.) However essential that the duty value given by the above equation be smaller than the duty value computed below (non-continuous mode). Duty ...
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... Power Supply Category 2: 4. Switching Regulators Cal No.: S-8323/24/27/28 Related Documents: Question: What is the basic concept of the S-8323 peak current? Answer: 1. Ipk in boosting The basic concept is as follows: Loss Pon of VIN due the figure below is: 1 Pon = × L × fosc × Ipk 2 ...
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... The basic concept is as follows: Loss Pon of VIN due the figure below is: 1 Pon = × L × fosc × Ipk 2 Loss Pon of VIN due the figure below is: Poff = Assuming that + is equal to energy Pout supplied from Vout, Iout × Vout = Pon ...
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... PD (0.23w) Where, I contave: Average current that flows through the external MOS FET, TRS at the time of ton. This is a measured value (see the waveforms below). duty: Ratio of ton to the switching period. This is a measured value (see the waveforms below). Ron: Drain-source resistance value when Siliconix/TN0200T comes on ...
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... Output Voltage (V) VOUT 4.94 4.92 4.90 4.88 -0.00001 S-8328B50 VIN=1.8V,Iout=200mA Iout=200mA <Remarks> FAQ No.: 11S8323008 Waveforms l contave ton -0.000005 0 0.000005 TIME (sec) 58 1.60 1.40 1.20 Coil Current 1.00 Icoil (A) 0.80 0.60 0.40 0.00001 VOUT Icoil ...
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... What is the maximum temperature coefficient of the output voltage? Answer: The worst temperature coefficient of the output voltage is as follows: S-8323~8 410 ppm/°C When this value is applied to VOUT=2 V, the temperature coefficient of the output voltage, Vout/ Ta (mV/°C), as defined by the SII specifications, is given as: S-8323~8 0.82 mV/°C (410 ppm/° Note that this is an actual value and is not guaranteed as a specification. < ...
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... S-8323/24/27/28 Related documents: Question: At start-up of S-8323~4, a large peak current flows through the CONT terminal possible that the peak current could cause a loss that exceeds the power dissipation? Answer: The power dissipation for S-8323~4 is 500 mW when the SOT-89 package is used, and 150 mW when the SOT-23 package is used ...
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... Power dissipation ¸ ( 0.001 0.001 <Remarks> FAQ No.: 11S8323005 0.01 0 0.01 0 tpk (sec) TIME (sec) 61 100 100 ...
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... When turning off the power, switch off the VDD of IC and the GND side of the external resistance. Since Tr 3 and Tr 4 are off when the power is off, turn discharge Cout 2 through RC. Two sets of inputs for turning on the power, a positive logic and a negative logic, are required. ...
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... Compared with Figure 1, additional external parts are also required (two Tr’s and a capacitor). L Tr2 VIN Tr1 Cin ON/OFF <Remarks> FAQ No.: 11S8323004 S-8327/8E VOUT VDD Cout1 R1 RB Internal R2 EXT circuit VSS Tr3 Figure 2 ON/OFF 63 Tr4 OUT RC Cout2 Tr5 GND ...
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... When turning off the power, switch off VDD of IC and the GND side of the external resistance. Two sets of inputs for turning on the power, a positive logic and a negative logic, are required. To restrict the rush current, increase the capacitance that the soft start-up time is prolonged. ...
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... L Tr2 VIN Tr1 Cin ON/OFF <Remarks> FAQ No.: 11S8323003 S-8327/8E VOUT VDD Cout1 R1 RB Internal R2 EXT circuit VSS Tr3 Figure 2 ON/OFF 65 OUT GND ...
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... VOUT due to the fact that the power for the internal circuit is supplied from the VOUT terminal. For the separated VDD type (D, E, and G series), the EXT output amplitude is from GND to VDD due to the fact that the power-supply voltage for the internal circuit occurs at the VDD terminal. For example, the EXT output amplitude will be from GND to VIN when the potential of VIN is applied to the VDD terminal ...
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... How can we ensure high efficiency? Answer: Follow these instructions: - Make sure the allowable current (maximum rating) of the used coil is greater than the peak current of the coil. (If the current exceeds the allowable value, efficiency decreases due to magnetic saturation.) - Select an external diode with low VF characteristics and a short first-recovery time. ...