s-8460 Seiko Instruments Inc., s-8460 Datasheet
s-8460
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s-8460 Summary of contents
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... Available from 2 dry battery cells and 1 lithium cell to AC adapter. Package Package Name 16-Pin TSSOP The S-8460 is a PWM control CMOS step-up and step-down switching regulator controller which consists of an automatic-selection control circuit for step-up and step-down, a reference voltage circuit, an oscillation circuit, an error amplifier, a phase compensation circuit, etc ...
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... SW2 IN IN SD2 C VL Remark Diodes shown in the IC are parasitic diodes. Product Code • Product code : S-8460B00AFT-TB-G • Delivery form : Taping only 2 L BST VIN S-8460 Oscillation circuit EXT1 PWM automatic- selection circuit LX EXT2 Voltage source VL Overload protection ON / OFF T VSS DVSS ...
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... Boost capacitor connection pin for SW1 driving *1. No use except boosting this IC is allowed. *2. The VSS pin and DVSS pin are internally short-circuited. *3. The NC pin is electrically open. Connection of this pin to VIN or VSS is allowed. Seiko Instruments Inc. S-8460 Table 1 Pin Description * ...
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... STEP-UP OR DOWN, SINGLE-COIL, PWM CONTROL SWITCHING REGULATOR CONTROLLER S-8460 Absolute Maximum Ratings Parameter VIN pin voltage FB pin voltage ON/OFF pin voltage CSS pin voltage CPRO pin voltage BST pin voltage BST pin − LX pin voltage LX pin voltage EXT1 pin voltage EXT2, 3 pin voltage ...
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... V − − 0.4 V −0.1 − μA 0.1 −0.1 − μA 0.1 6.0 12.0 24.0 ms 1.25 2.5 5.0 ms − − − − S-8460 Measurement Circuit − ...
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... STEP-UP OR DOWN, SINGLE-COIL, PWM CONTROL SWITCHING REGULATOR CONTROLLER S-8460 Measurement Circuits 1. 47 μF A 0.1 μF 2. FDN337N F93 F93 47 μF 47 μF 0.1 μF FDN337N 6 VIN VL 4.7 μF A ON/OFF LX T CSS CPRO VSS DVSS 4700 pF 2200 pF Figure 4 CDRH104R 22 μH ON/OFF VIN BST EXT1 LX EXT2 RB411D VL T CPRO VSS DVSS 4.7 μ ...
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... The S-8460 automatically selects step-up operation or step-down operation to hold the output voltage constant according to the input voltage (V can be constructed using the S-8460, since the S-8460 works as a switching regulator for both step-up and step- down operation. Figure 6 shows the block diagram of the S-8460. ...
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... STEP-UP OR DOWN, SINGLE-COIL, PWM CONTROL SWITCHING REGULATOR CONTROLLER S-8460 1. 2 Step-up Operation SW1 V IN Parasitic diode Step-up operation is carried out by setting SW1 : ON, SW2 : OFF, and toggling SW3. The voltage V needed at the BST pin to turn SW1 on. For this purpose, the BST pin voltage (C ...
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... And if the switches, SW2 and SW3, are turned on simultaneously, the energy stored in the coil flows to V and is wasted. The S-8460 thus controls the switches in such a way that in operations involving SW1 SS and SW2, and involving SW2 and SW3 both switches are turned off simultaneously to avoid useless current flowing due to simultaneous turn-on of the switches ...
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... S-8460 1. 6 PWM Control The S-8460 is a DC-DC converter using a pulse width modulation method (PWM) and features a low current consumption. In conventional PFM DC-DC converters, pulse are skipped when the output load current is low, causing a fluctuation in the ripple frequency of the output voltage, resulting in an increase in the ripple voltage. ...
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... Overload Protection Circuit The S-8460 contains a built-in overload protection circuit. When the output voltage falls because of an overload despite the step-up operation or step-down, the S-8460 enters the step-up operation and holds the maximum duty step-up operation. If this maximum duty state lasts longer than the overload detection time (t to protect the switching transistors and the inductor ...
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... STEP-UP OR DOWN, SINGLE-COIL, PWM CONTROL SWITCHING REGULATOR CONTROLLER S-8460 Continuous mode at step-up operation + V V OUT F = × Continuous mode at step-down operation × V OUT = + OUT × 2 fosc L V Where f (= 300 kHz) is the oscillation frequency the inductance value of the coil, and V OSC forward voltage ...
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... V . Immediately after the power is turned on, or the shutdown selecting MOS FETs, thorough evaluation under the actual condition is Seiko Instruments Inc. . The EXT1 pin voltage swings between V ) when SW2 is off. The breakdown voltage IN voltage since the S-8460 + ...
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... STEP-UP OR DOWN, SINGLE-COIL, PWM CONTROL SWITCHING REGULATOR CONTROLLER S-8460 5. Output Voltage Adjustment The output voltage is externally set in the S-8460. The output voltage can be set and adjusted in the output voltage setting range (2 adding external resistors (R Temperature gradient can be added by inserting a thermistor in series to R The output voltage is set as (R exceed 2 MΩ ...
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... SII claims no responsibility for any disputes arising out connection with any infringement by products including this IC of patents owned by a third party. ) and a Schottky diode (SD2) can be connected to the VL pin. VL The operation returns to normal when the load of 1 μA or more is attached. Seiko Instruments Inc. S-8460 PRO 15 ...
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... STEP-UP OR DOWN, SINGLE-COIL, PWM CONTROL SWITCHING REGULATOR CONTROLLER S-8460 Characteristics (Typical Data) 1. Examples of Major Characteristics (1) Current Consumption 2 (I SS2 140 120 Ta = −40°C 100 25° (3) Current Consumption at Shutdown (I Input Voltage ( 3.0 2.5 2.0 25° −40°C 1 ...
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... V ( vs. EXT2L ) −40°C 25°C 85° ( vs. EXT3L ) −40°C 85°C 25° ( 2200 pF PRO 25°C 85° −40° (V) IN S-8460 vs. PRO ...
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... STEP-UP OR DOWN, SINGLE-COIL, PWM CONTROL SWITCHING REGULATOR CONTROLLER S-8460 2. Examples of Transient Response Characteristics : 0 V → (1) Power- V/div OUT (1 V/div ms/div V/div OUT (1 V/div ms/div) (2) ON/OFF Pin Response (V ...
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... IN 100 mA I OUT 10 μ OUT (0.1 V/div 18 100 mA I OUT 10 μ OUT (0.1 V/div) Seiko Instruments Inc. S-8460 : 3.3 V) OUT :100 mA → 10 μ 2.64 V OUT IN t (40 ms/div) : 100 mA → 10 μ 4.95 V OUT IN t (40 ms/div) : 100 mA → 10 μ 18.0 V OUT ...
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... STEP-UP OR DOWN, SINGLE-COIL, PWM CONTROL SWITCHING REGULATOR CONTROLLER S-8460 (4) Input Voltage Fluctuation (V : 2.7 V → 5 (1.0 V/div OUT (0.1 V/div) t (0.5 ms/div) : 2.2 V → 18 (4.0 V/div OUT (0.1 V/div) t (0.5 ms/div 2.7 V → 5.0 V, 5.0 V → 2.7 V, 2.2 V → 18.0 V → 2 ...
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... CDRH104R/22 μH *3 CDRH104R/22 μH = 100 kΩ 330 pF FB2 fzfb = 100 kΩ 470 pF FB2 fzfb = 100 kΩ 220 pF FB2 fzfb Seiko Instruments Inc. S-8460 Diode Output Input SD1 Capacitor Capacitor 47 μF × μF × 2, 0.1 μF MA2Q737 D1FH3 MA2Q737 D1FH3 MA2Q737 D1FH3 MA2Q737 ...
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... Remark Values for and C FB1 FB2 External Parts List for Ripple Data Table 5 External Parts for Input Voltage vs. Ripple Voltage Characteristics Data Output No. Product Name Voltage (31) S-8460B00AFT 3.3 V (32) (33) (34) 2.5 V (35) 5 230 kΩ, R *1. External parts : R FB1 = 150 kΩ, R *2. External parts : R FB1 = 400 kΩ ...
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... A max 0.4 V min 0.046 Ω max. (V DS(ON max 2.8 A max 0.65 V min 0.115 Ω max 2.5 V), SOT-23 package max 1.7 A max 0.4 V min 0.100 Ω max. (V DS(ON) ® package S-8460 13.5 mm 4.0 mm max. max. = 2.5 V 2.5 V 2.5 V 2.5 V ...
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... I (mA) OUT = 3.3 V) (7) S-8460B00AFT (V OUT CPH6401, MA2Q737, CDRH104R/10 μH CPH6401,MA2Q737,CDRH104R/10 μ H 100 =2. (mA) OUT 24 vs. efficiency (η) characteristics when the S-8460 is used under OUT (2) S-8460B00AFT (V 100 =2.7V 3.0V 60 3.3V 50 100 1000 1 (4) S-8460B00AFT (V 100 4. 3. 100 1000 ...
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... S-8460B00AFT (V OUT CPH6401, MA2Q737, CDRH104R/10 μH CPH6401,MA2Q737,CDRH104R/10 μ H 100 =3. (mA) OUT (10) S-8460B00AFT (V 100 5. 100 1000 1 (12) S-8460B00AFT (V 100 5. 100 1000 1 (14) S-8460B00AFT (V 100 7. 5. 100 1000 1 (16) S-8460B00AFT (V 100 7. 5. ...
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... V ( 3.3 V) (23) S-8460B00AFT (V OUT CPH6401, MA2Q737, CDRH104R/10 μH CPH6401,MA2Q737,CDRH104R/10 μ H 100 66mA ( vs. efficiency (η) characteristics when the S-8460 is used under IN (18) S-8460B00AFT (V 100 200mA 66mA (20) S-8460B00AFT (V 100 200m 100mA =50mA OUT ...
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... OUT ) Characteristics OUT ) vs. output voltage (V OUT 3.3V =2.2V 2.7V 4.95V 18V 100 1000 (27) S-8460B00AFT (V 5.25 18V 2.5V 5.20 5.15 =2.2V IN 5.10 5.05 3.75V 5V 5V 5.00 4.95 100 1000 Seiko Instruments Inc. ) characteristics when the S-8460 is used OUT = 5.0 V) OUT CPH6401, MA2Q737, CDRH104R/22 μH CPH6401,MA2Q737,CDRH104R/22 μ =2.2V IN 18V 7. 100 1000 I (mA) OUT S-8460 27 ...
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... V ( Characteristics OUT ) vs. output voltage ( (30) S-8460B00AFT (V 5.10 5.08 50mA 5.06 5.04 100mA 200m A 5.02 5. Seiko Instruments Inc. ) characteristics when the S-8460 is used OUT = 5.0 V) OUT CPH6401, MA2Q737, CDRH104R/22 μH CPH6401,MA2Q737,CDRH104R/22 μ H 200m A 200 mA 100mA I =0.1mA 50mA OUT (V) IN Rev.2.1 _00 ...
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... I OUT (35) S-8460B00AFT ( OUT Seiko Instruments Inc. ) characteristics when the S-8460 is used under rip = 3.3 V) OUT CPH6401, MA2Q737, CDRH104R/10 μ 200 mA OUT ( 5.0 V) OUT CPH6401, MA2Q737, CDRH104R/22 μH ...
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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 ...