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Power Supply IC S1F76980 Technical Manual SEIKO EPSON CORPORATION Rev.1.0...
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Seiko Epson. Seiko Epson reserves the right to make changes to this material without notice. Seiko Epson does not assume any liability of any kind arising out of any inaccuracies contained in this material or due to its application or use in any product or circuit and, further, there is no representation that this material is applicable to products requiring high level reliability, such as, medical products.
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Configuration of product number DEVICES 76980 0C00 Packing specifications Specifications Shape (F:QFN) Model number Model name (F : Power Supply) Product classification (S1:Semiconductors)
1. DESCRIPTION 1. DESCRIPTION The S1F76980 series is a low consumption current power supply input control IC, which monitors the voltage of 3-system input power supply and is capable of continuously switching power supply of the system selected in the priority sequence in the IC. For operations below the operating voltage, the product also guarantees operations in reduced power mode by setting the output level of the control signal to Hi-Z.
Power Switching voltage control monitoring circuit circuit BSEL Power voltage monitoring circuit CUDLY ONOFSW CSFT Power voltage monitoring circuit CBDLY Power switching circuit Power-on reset circuit Reference CDET voltage UDET generator BDET Fig.4.1 Block diagram EPSON S1F76980 Technical Manual (Rev.1.0)
This circuit controls output of a signal that selects optimum input power supply according to input conditions of three power supplies (V , and V ) and in the priority sequence set in the IC. The priority sequence of and V can also be switched during operation, using the external pin BSEL. S1F76980 Technical Manual (Rev.1.0) EPSON...
(battery) power supply input-side pin. 3-system select power supply output-side pin. GND pin. Pin used to connect the smoothing capacitor in the IC. • Test pin Pin Name Function Normally fixed to LOW. Normally fixed to LOW. S1F76980 Technical Manual (Rev.1.0) EPSON...
8. FUNCTIONAL DESCRIPTION 8.1 Operation Description The S1F76980 series is a low consumption current power supply input control IC, which monitors the voltage of 3-system input power supply and is capable of continuously switching power supply of the system selected in the priority sequence in the IC.
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The recommended value of the capacitor is approximately 50ms for 6800pF. Typ. Release delay setting time TUDLY [ms] = Set coefficient (7353) × C [µF] In case of the recommended C=6800[pF], the release delay time is TUDLY=50[ms]. S1F76980 Technical Manual (Rev.1.0) EPSON...
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In case of the recommended C=6800[pF], the release delay time is TBDLY=1[S]. Typ. For detecting voltage = 2.8V, detecting voltage dead setting time TBDLY [S] = Set coefficient (250) × C [µF] In case of the recommended C=6800[pF], the release delay time is TBDLY=1.7[S]. EPSON S1F76980 Technical Manual (Rev.1.0)
Fig.8.4.1 shows the configuration diagram of power supply selection switches, that are configured outside the The O*1 (OC1, OU1, and OB1) pin performs over voltage limiter control while the O*2 (OC2, OU2, and OB2) pin controls backflow prevention. Fig.8.4.1 Switch configuration S1F76980 Technical Manual (Rev.1.0) EPSON...
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(V ) and V input enabled, elimination of backflow potential between input power supply (V ) and V (Typ. 19mV) input disabled Fig.8.4.2 State transition at V power-on EPSON S1F76980 Technical Manual (Rev.1.0)
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) and V (Typ. 19 mV) input disabled, V input enabled, backflow potential between input power supply (V ) and V ⇔ V Fig.8.4.3 V power supply switching state transition 1 S1F76980 Technical Manual (Rev.1.0) EPSON...
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(ON-ON), backflow from V prevented on the V side only. (OB1:ON, OB2:ON, OU1:OFF, OU2:OFF, OC1:ON, OC2:OFF) State G: V and V input power supplies selected simultaneously (ON-ON), full on state (OB1:ON, OB2:ON, OU1:OFF, OU2:OFF, OC1:ON, OC2:ON) EPSON S1F76980 Technical Manual (Rev.1.0)
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SEIKO EPSON, however, shall not be liable for any defective conditions or the like due to backflow to input power supply caused by ON-ON switching.
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Soft start setting time TSFT [ms] = Set coefficient (70) × C [µF] For recommended C = 0.01 [µF], soft start time: TSFT = 0.7 [ms] = 1.05V CSFT CSFT RFB1 RFB2 Fig.8.4.4 Overvoltage limiter circuit diagram EPSON S1F76980 Technical Manual (Rev.1.0)
This state is not effective for the IC, so we recommend that the IC be connected to a discharge resistor. The recommended resistance value is between 1 and 2.2 MegΩ. If a lower resistance is required depending on setting conditions, however, determine the appropriate value after careful evaluation. S1F76980 Technical Manual (Rev.1.0) EPSON...
(Note 10) Do not externally apply the voltage to the output pin. (Note 11) Using with a condition exceeding the above absolute maximum rating may result in malfunction or unrecoverable damage. Moreover, normal function may be achieved temporarily but its reliability may be significantly low. EPSON S1F76980 Technical Manual (Rev.1.0)
(Note 13) It is recommended to use a tantalum capacitor of ESR = 1 Ω or more. (Note 14) Connect 47 µF capacitors in parallel to increase the capacity. (Note 15) It is recommended to use ON Semiconductor NTHD2102P. S1F76980 Technical Manual (Rev.1.0) EPSON...
(Note 16) This value may be higher than the current value described above by detecting or releasing the output guarantee voltage near the output guarantee circuit VHIZ. If the voltage drops to below VHIZ, this value is set to the current value of V -system consumption current 3. EPSON S1F76980 Technical Manual (Rev.1.0)
V =2.25V (Note 20) The V power is used as the standard value at V 4.95V. (Note 21) The V power is used as the standard value at V 2.25V. S1F76980 Technical Manual (Rev.1.0) EPSON...
The capacity accuracy of capacitor is not included in the standard values. We recommend that you select highly accurate capacitors. (Note 24) This is the standard value for the release delay capacitor at CUDLY=6800pF and V 3.75V. EPSON S1F76980 Technical Manual (Rev.1.0)
(Note 27) This is the standard value for the dead time setting capacitor at CBDLY=6800pF and =2.75V 4.2V. (Note 28) This is the standard value for the dead time setting capacitor at CBDLY=6800pF and =1.55V 3V. S1F76980 Technical Manual (Rev.1.0) EPSON...
: 85°C OUTH Output voltage value at V : -30°C OUTL Output voltage value at V : 25°C OUTM (Note 31) The standard value does not include an error by the feedback resistance voltage dividing ratio. EPSON S1F76980 Technical Manual (Rev.1.0)
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9. ELECTRICAL CHARACTERISTICS (Note 32) Measurement of transmission delay time (Nch open drain output) +C/U/BDET -C/U/BDET TPHLC/U/B TPLHC/U/B VSO(5V) C/U/BDET S1F76980 series C/U/BDET S1F76980 Technical Manual (Rev.1.0) EPSON...
(17) RCDET= (18) RUDET= (19) RBDET=470kΩ, (20) CSFT=0.01µF (21) RV = (22) RV = (23) RV =1MegΩ (Note 33) The recommended connection diagram is carefully evaluated, ensure to verify characteristics by installing the machine onto the set before using it. EPSON S1F76980 Technical Manual (Rev.1.0)
(19) RCDET= (20) RUDET= (21) RBDET=470kΩ, (22)CSFT=0.01µF (23) RV = (24) RV = (25) RV =1MegΩ (Note 34) The recommended connection diagram is carefully evaluated, ensure to verify characteristics by installing the machine onto the set before using it. S1F76980 Technical Manual (Rev.1.0) EPSON...
11. DIMENSIONAL OUTLINE DRAWING (QFN4-24) 11. DIMENSIONAL OUTLINE DRAWING (QFN4-24) Top View Reference Index Bottom View Dimension in Millimeters Symbol Min. Nom. Max. 0.17 Index 0.05 1 = 1 mm EPSON S1F76980 Technical Manual (Rev.1.0)