s-8424a Seiko Instruments Inc., s-8424a Datasheet
s-8424a
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s-8424a Summary of contents
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... Still video cameras • Memory cards • SRAM backup equipment The S-8424A Series is a CMOS IC designed for use in the switching circuits of primary and backup power supplies on a single chip. It consists of two voltage regulators, three voltage detectors, a power supply switch and its controller, as well as other functions. ...
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... V (0.1 V steps) DET1 −V : 1.7 to 3.4 V (0.1 V steps ) DET2 −V : 1.7 to 3.4 V (0.1 V steps) DET3 + SW1 DET1 product with a voltage other than above is required, contact our sales representative. S-8424A Output CS Voltage Voltage (V) (V) − OUT DET1 DET1 3.000 3.000 3 ...
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... Rev.2.2 _00 Block Diagram VIN CS Voltage detector CS VOUT M1 REG2 V SW1 Detector V SW2 Detector Switch controller VSS Figure 1 Block Diagram Seiko Instruments Inc. BATTERY BACKUP SWITCHING IC S-8424A Series VBAT PREEND PREEND Voltage detector RESET RESET Voltage detector VRO REG1 3 ...
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... BATTERY BACKUP SWITCHING IC S-8424A Series Pin Configurations 8-Pin TSSOP Top View VSS PREEND VBAT Figure 2 8-Pin SON(B) Top View 1 8 VSS 2 7 PREEND 3 6 VBAT Figure 3 4 Pin No. Symbol 1 VSS VRO 2 VIN PREEND VOUT 3 VBAT RESET ...
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... T stg (2) When not mounted on board 400 8-Pin SON(B) 300 200 100 0 100 150 0 Figure 4 Power Dissipation of Package Seiko Instruments Inc. BATTERY BACKUP SWITCHING IC S-8424A Series (Unless otherwise specified 25°C) Ratings −0 + −0 +0 −0 +18 V ...
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... BATTERY BACKUP SWITCHING IC S-8424A Series Electrical Characteristics 1. S-8424AAAxx Parameter Output voltage 1 Dropout voltage 1 Load stability 1 Input stability 1 Output voltage temperature coefficient 1 Output voltage 2 Dropout voltage 2 Load stability 2 Input stability 2 Output voltage temperature coefficient 2 Primary power input voltage CS detection voltage CS release voltage ...
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... V, Unload I V SS1 IN BAT I BAT1 I = Open 3.0 V, Unload V BAT2 IN BAT ⎯ V BAT Seiko Instruments Inc. BATTERY BACKUP SWITCHING IC S-8424A Series (Unless otherwise specified 25°C) Min. Typ. Max. 3.234 3.300 3.366 ⎯ 356 474 ⎯ 50 100 ⎯ ⎯ ±100 ⎯ ...
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... BATTERY BACKUP SWITCHING IC S-8424A Series 3. S-8424AACxx Parameter Output voltage 1 Dropout voltage 1 Load stability 1 Input stability 1 Output voltage temperature coefficient 1 Output voltage 2 Dropout voltage 2 Load stability 2 Input stability 2 Output voltage temperature coefficient 2 Primary power input voltage CS detection voltage CS release voltage RESET detection voltage ...
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... V, Unload BAT SS1 I BAT1 I = Open 3.0 V, Unload V BAT2 IN BAT ⎯ V BAT Seiko Instruments Inc. BATTERY BACKUP SWITCHING IC S-8424A Series (Unless otherwise specified 25°C) Min. Typ. Max. 4.900 5.000 5.100 ⎯ 356 474 ⎯ 50 100 ⎯ ⎯ ±100 ⎯ ...
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... BATTERY BACKUP SWITCHING IC S-8424A Series 5. S-8424AAExx Parameter Output voltage 1 Dropout voltage 1 Load stability 1 Input stability 1 Output voltage temperature coefficient 1 Output voltage 2 Dropout voltage 2 Load stability 2 Input stability 2 Output voltage temperature coefficient 2 Primary power input voltage CS detection voltage CS release voltage RESET detection voltage ...
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... I V SS1 IN BAT I BAT1 = Open 3.0 V, Unload I V BAT2 IN BAT ⎯ V BAT Seiko Instruments Inc. BATTERY BACKUP SWITCHING IC S-8424A Series (Unless otherwise specified 25°C) Min. Typ. Max. 3.136 3.200 3.264 ⎯ 356 474 ⎯ 50 100 ⎯ ⎯ ±100 ⎯ ...
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... BATTERY BACKUP SWITCHING IC S-8424A Series 7. S-8424AAGxx Parameter Output voltage 1 Dropout voltage 1 Load stability 1 Input stability 1 Output voltage temperature coefficient 1 Output voltage 2 Dropout voltage 2 Load stability 2 Input stability 2 Output voltage temperature coefficient 2 Primary power input voltage CS detection voltage CS release voltage detection voltage ...
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... I V SS1 IN BAT I BAT1 = Open 3.0 V, Unload I V BAT2 IN BAT ⎯ V BAT Seiko Instruments Inc. BATTERY BACKUP SWITCHING IC S-8424A Series (Unless otherwise specified 25°C) Min. Typ. Max. 4.900 5.000 5.100 ⎯ 356 474 ⎯ 50 100 ⎯ ⎯ ± 100 ⎯ ...
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... BATTERY BACKUP SWITCHING IC S-8424A Series 9. S-8424AAJFxx Parameter Output voltage 1 Dropout voltage 1 Load stability 1 Input stability 1 Output voltage temperature coefficient 1 Output voltage 2 Dropout voltage 2 Load stability 2 Input stability 2 Output voltage temperature coefficient 2 Primary power input voltage CS detection voltage CS release voltage RESET detection voltage ...
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... I V SS1 IN BAT I BAT1 = Open 3.0 V, Unload I V BAT2 IN BAT ⎯ V BAT Seiko Instruments Inc. BATTERY BACKUP SWITCHING IC S-8424A Series (Unless otherwise specified 25°C) Min. Typ. Max. 3.136 3.200 3.264 ⎯ 123 167 ⎯ 50 100 ⎯ ⎯ ± 100 ⎯ ...
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... BATTERY BACKUP SWITCHING IC S-8424A Series Test Circuit 1. VIN VRO or VOUT V IN VSS 3. VBAT VOUT VIN V PREEND IN VSS 5. VOUT VIN F.G . VSS VBAT V 7. VIN VBAT BAT Leave open and measure the value after applying VIN ↓ μ ...
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... Rev.2.2 _00 Operation Timing Chart (V) OUT V (V) BAT V ( PREEND ( ) V V RESET Remark CS, PREEND and RESET are pulled BATTERY BACKUP SWITCHING IC . Y-axis is an arbitrary scale. OUT Figure 6 Operation Timing Chart Seiko Instruments Inc. S-8424A Series 17 ...
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... The functions and operations of the above-listed elements are described below. 1. Voltage Regulators The S-8424A Series features on-chip voltage regulators with a small dropout voltage. The voltage of the VRO and VOUT pins (the output pins of the voltage regulator) can separately be selected for the output voltage in ...
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... Figure 8 Switch Unit IN ) can be set to 77 ± ± the CS release voltage SW1 Seiko Instruments Inc. BATTERY BACKUP SWITCHING IC S-8424A Series (VBAT pin voltage). The detection voltage BAT ). The output is the low level when the voltage is ). (VOUT pin voltage). The detection ...
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... BATTERY BACKUP SWITCHING IC S-8424A Series 3.2 V Detector SW2 The V detector monitors the VOUT pin voltage and keeps the CS release voltage output low until the SW2 VOUT pin voltage rises to V voltage is more than the CS release voltage ( + V output voltage of voltage regulator 2 (V voltage when the VIN pin voltage drops to less than the CS detection voltage ( − V ...
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... 25°C) with the VBAT pin grounded (VSS pin). (output current) at maximum., and V OUT VOUT VIN REG2 Figure 9 Definition of V Seiko Instruments Inc. BATTERY BACKUP SWITCHING IC S-8424A Series = 10 to 500 μ A). OUT – V (max.) is output to the VOUT pin at BAT dif V dif ...
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... BATTERY BACKUP SWITCHING IC S-8424A Series Transient Response 1. Line Transient Response Against Input Voltage Variation The input voltage variation differs depending on whether the power supply input ( square wave) is applied or the power supply variation (6 V and 10 V square waves) is applied. This section describes the ringing waveforms and parameter dependency of each type ...
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... VIN S-8424A Series P.G. Undershoot Figure 15 Test Circuit C OUT (100 μ s/div (100 μ s/div) Seiko Instruments Inc. S-8424A Series VOUT Oscillo-scope R L VSS μ mA ° C OUT μ mA ° ...
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... BATTERY BACKUP SWITCHING IC S-8424A Series Reference data: Dependency of output current (I temperature (Ta) For reference, the following pages describe the results of measuring the ringing amounts at the VOUT and VRO pins using the output current (I temperature (Ta) as parameters. 1.1 I Dependency OUT (1) VOUT pin = = 22 μ ...
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... I OUT 0.05 =22 μF C OUT 0.00 –50 0 (2) VRO pin = 22 μ ° C OUT Δ V (V) IN (2) VRO pin 50 100 Ta ( ° C) Seiko Instruments Inc. BATTERY BACKUP SWITCHING IC S-8424A Series = 30 mA μ ° 0.30 0.25 0.20 0.15 0.10 0.05 0. Δ V (V) IN 0.30 0.25 0.20 0.15 0.10 =6 ↔ ...
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... BATTERY BACKUP SWITCHING IC S-8424A Series 2. Load Transient Response Based on Output Current Fluctuation The overshoot and undershoot are caused in the output voltage if the output current fluctuates between 10 μ A and is between 10 μ A and 30 mA) while the input voltage is constant. Figure 18 shows the output voltage ...
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... C RO 0.12 0.10 0.08 0.06 0.04 0.02 0. (V) (2) VRO pin μ F) Seiko Instruments Inc. BATTERY BACKUP SWITCHING IC S-8424A Series ), output variation width ( Δ I OUT = 22 μ and 10 μ ° ( 6 and 10 μ ° 0.30 ...
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... BATTERY BACKUP SWITCHING IC S-8424A Series 2.3 Δ I Dependency OUT Δ I and Δ I show the fluctuation between the low current stabilized at 10 μ A and the high current. For OUT RO example, Δ means a fluctuation between 10 μ A and 10 mA. OUT (1) VOUT pin = 22 μ ...
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... VRO VIN VBAT VOUT + 10 μF S-8424A Series V VSS RESET CS PREEND V V OUT OUT 100 kΩ 100 kΩ Figure 22 Standard Circuit Seiko Instruments Inc. BATTERY BACKUP SWITCHING IC S-8424A Series μF 1 kΩ V OUT + 10 μF 0.1 μ OUT 100 kΩ 29 ...
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... BATTERY BACKUP SWITCHING IC S-8424A Series Precautions • In applications with small I exceed standard levels. Set I • Attach the proper capacitor to the VOUT pin to prevent the RESET voltage detector (which monitors the VOUT pin) from coming active due to undershoot. • Watch for overshoot and ensure it does not exceed the ratings of the IC chips and/or capacitors attached to the VRO and VOUT pins. • ...
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... VSS Figure 24 Application Circuit 2 Card unit VIN VOUT + S-8424A 10 μ F Series PREEND RESET VBAT VSS Figure 25 Application Circuit 3 Seiko Instruments Inc. BATTERY BACKUP SWITCHING IC S-8424A Series + 10 μ F VCC 100 k Ω Microcontroller INT RESET 10 μ 100 k Ω SRAM 0.1 μ ...
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... BATTERY BACKUP SWITCHING IC S-8424A Series Characteristics 1. Voltage Regulator Unit (V 1.1 Input Voltage (V ) vs. Output Voltage ( ° mA, 30 mA, 50 mA 2.8 2.4 2.0 2.0 3 − 40 ° mA, 30 mA, 50 mA 2.8 2.4 2.0 2.0 3.0 V 1.2 Input Voltage (V ) vs. Output Voltage ( ° ...
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... Output voltage ( 100 1.10 Input Stability ( 100 1.12 Load Stability ( 100 Seiko Instruments Inc. BATTERY BACKUP SWITCHING IC S-8424A Series ) vs. Dropout Voltage (V OUT drop2 1.0 0 ° °C 0.6 − 40 ° C 0.4 0.2 0.0 0 0.02 0.04 I (A) OUT ) vs. Output Voltage (V OUT OUT 3 ...
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... BATTERY BACKUP SWITCHING IC S-8424A Series 2. Voltage Detector 2.1 CS Voltage Detector ( − V (1) Detection voltage ( − V DET1 characteristics 20 Based − voltage when Ta is 25°C DET1 0 − 10 − 20 − 40 − (°C) (3) Output current (I ) temperature characteristics SINK 2 BAT − ...
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... BAT − 40 − ° 2.6 V) DET3 (2) Output current (I ) temperature ) voltage DET3 100 ( 100 Seiko Instruments Inc. BATTERY BACKUP SWITCHING IC S-8424A Series ) characteristics SINK ° 0.0 1.0 2.0 3 1.7 V 4.0 35 ...
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... BATTERY BACKUP SWITCHING IC S-8424A Series 3. Switch Unit 3.1 Switch Voltage (V ) Temperature Characteristics 3.2 CS Output Inhibit Voltage (V SW1 20 10 voltage when ° C Based on V SW1 0 −10 −20 −40 − ° C) 3.3 Input Voltage (V ) vs. V BAT Switch BAT Resistance(R ) Characteristics ...
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... Ta ( ° 4.2 V vs. V SS1 BAT Characteristics 2.0 1.5 1.0 0.5 0 (2) I BAT2 2.0 1.5 1.0 0.5 0 100 Seiko Instruments Inc. BATTERY BACKUP SWITCHING IC S-8424A Series Consumption Current (I BAT2 BAT2 ° C 25°C −40 ° C 2.0 2.4 2.8 3.2 3.6 V (V) BAT = open 3 BAT −40 − ° ...
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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 ...