s1f78520 Epson Electronics America, Inc., s1f78520 Datasheet
s1f78520
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s1f78520 Summary of contents
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... DESCRIPTION The S1F78520 is a power IC which can generate two stabilized output voltages of 3.3 V (or 2 2.5 V) and 2.5 V (or 2 1.8 V) using the Li-ion battery. The 3.3 V range output is being generated through the LDO (series regulator). The 2.5 V range output is being generated through the charge pump type DC/DC converter consisting of built-in CMOS transistors ...
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... S1F78520 BLOCK DIAGRAM V DD VO1LV1, 2 VO1LV0 VO2LV1, 2 VO2LV0 ROSC1 (1) Oscillation ROSC circuit OSCIN XSTBY VSENS (2) Low voltage detection circuit VSEL (6) Bias circuit Reference current Reference voltage XPOFF (7) Shut down CPG (4) LDO (series regulator) (3) Voltage dropping type charge pump (5) Power good detection circuit Fig ...
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... Operations of all the circuits can be interrupted by setting the shut down pin XPOFF to the V <Note> DD2 Rev. 1.2 potential as the reference voltage. The specified voltage is select OUT1 = SS2 SS3 S1F78520 pin. Provision and V are satisfying the specified OUT2 level ...
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... S1F78520 PIN ASSIGNMENT SSOP3–24pin S1F78520M0A01 Pin No Pin name Pin No. Pin name 1 XPOFF 13 2 VO2LV1 14 3 VO2LV0 15 4 C1N 16 5 C1P OUT2 CPG 20 9 ROSC1 OSCIN 23 12 XSTBY 24 XVDET VSENS V DD ...
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... V level Not for use * * DD level. level. The detection voltage generated inside the IC becomes valid * level level when the input power pin S1F78520 level while the operation OUT2 OUT2 OUT2 OUT2 is at the low voltage level. DD and V . OUT1 ...
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... S1F78520 (2) Power pins Pin name I/O Pin No Positive side input power pin Positive side input power pin. DD2 Negative side input power pin Negative side input power pin. SS2 Negative side input power pin. ...
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... FUNCTIONAL DESCRIPTION Operational description S1F78520 is a power supply IC which generates two output voltages, 3.3V (or 2.9V or 2.5V) and 2.5V (or 2.0V or 1.8V), stabilized from Li-ion batteries. High conversion efficiencies can be aquired under heavy loads by standby input signal. While low consuming current operations can be realized under light load state. ...
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... S1F78520 Standby mode By setting the standby mode signal XSTBY externally, current consumption of this IC can be suppressed drastically. The time required after the mode change is made with the standby pin until the internal mode of the IC is stabilized should be max. 10ms to min. 0s. Complete timing design should be effected when using the standby mode ...
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... V +VDET: 3.39 V • (Rb)/(Ra + Rb) = VSENS ...................... (Formula 1) • (Ra + Rb)/(Rb) [V] ................................. (Formula 2) • (Rb)/(Ra + Rb) = VSENS ...................... (Formula 3) • (Ra + Rb)/(Rb) [V] ................................. (Formula 4) + – 1.00V REF1 1.025V REF2 REF2 S1F78520 pin. For setting of the DD voltage value satisfying the DD XVDET 9 ...
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... S1F78520 Power good detection circuit Power good signals are detected when both of the output pins V voltage. As for the power good detection range, provision of a hysteresis width for the lower limit value of detection according to Fig. 5 indicated below is effective to prevent occurrences of unstable power good signal outputs in the neighborhood of the detection limit value range ...
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... Example : CDPG = 0.1 F, RDPG = 1MEG TDPG 0.1 F Output voltage V , OUT1 V OUT2 Capacitor voltage Power good signal PG Rev. 1.2 CDPG (F) RDPG ( ) ........................... (Formula 5) 1MEG = 0.1 (S) Delay pin threshold value voltage (VTCPG Delay time (TDPG) Fig. 6 Outline drawing for delay settings S1F78520 Power good detection voltage 11 ...
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... S1F78520 V DD RDPG CPG CDPG Fig. 7 Connection diagram in the neighborhood of the power good detection circuit 12 [Internal structure of the S1F78520] LDO Voltage dropping type charge pump + – Reference voltage + – Reference voltage V OUT1 V OUT2 PG Rev. 1.2 ...
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... V –0 — 240 mA — 120 mA — 100 mA — 520 mW – –55 150 C — 260 · · s S1F78520 Remarks V V — DD, DD2 V — OUT1, V — OUT2 <Note 1> — — DD, DD2 V — OUT1 V — OUT2 — — ...
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... S1F78520 ELECTRICAL CHARACTERISTICS DC characteristics LDO (series regulator), voltage dropping type charge pump Item Symbol Input supply voltage V DD High level input voltage V IH Low level input voltage V IL Input leak current I LIN Output voltage 11 V OUT11 Output voltage 12 V OUT12 Output voltage 13 ...
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... Normal mode OUT2 OUT2 –30 C Topr 0.05 mA OUT2 –30 C Topr Standard connection 1 : XPOFF = HIGH (Normal mode) : XSTBY = HIGH (Normal mode) S1F78520 Rating Unit Remarks Typ. Max. — — — — — — — — — ...
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... S1F78520 Low voltage detection Item Symbol Detection voltage –VDET Hysteresis width VHYS Reference detection V REF1 voltage 1 Reference detection V REF2 voltage 2 Min. operating voltage VVDDL Output current IVDET (Driver output pin) Off leak current IVDOFF (Driver output pin) Transfer delay time TPLH ...
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... V = 3.6V 2. 3.6V DD 0.06 CPG = 0.1V Applicable pin: V OUT1 — –30 C Topr 85 C Applicable pin: V OUT2 Output voltage setting: 2.0 V — –30 C Topr Standard connection 1 : XPOFF = HIGH (Normal mode) : XSTBY = HIGH (Normal mode) S1F78520 Rating Unit Remarks Typ. Max. 2.91 3.00 V — 2.62 2.70 V — 2.23 2.30 V — 2.23 2.30 V — 1.74 1.80 V — ...
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... S1F78520 REFERENCE EXTERNAL CONNECTION (AN EXAMPLE) Standard connection CDD VO1LV1, VO1LV0 VO2LV1, VO2LV0 RS OSCIN XSTBY VSEL XPOFF V SS Recommended values for the external parts ROSC = 1MEG Ra = (Make the detection voltage setting according to the formulae 2 and 4 (Make the detection voltage setting according to the formulae 2 and 4 RVD = RPG = 470k CDD = CDD2 = 4 ...
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... DIMENSIONAL OUTLINE DRAWING SSOP3–24pin 0.375 Typ. 7.9 0.2 0.65 Rev. 1.2 0.5 0.2 +0.1 0.22 –0.05 0.12 M 0.10 S1F78520 EXAMPLE Unit : mm 19 ...
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... S1F78520 NOTICE: No part of this material may be reproduced or duplicated in any form or by any means without the written permission of 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 ...