MAL219699003E3 Vishay

TECHNICAL NOTE VISHAY BCCOMPONENTS www.vishay.com Aluminum Capacitors Technical Note TM Power Management Solution With 196 HVC ENYCAP for Mini Charger and Fixed Voltage Supply Board By Gerald Tatschl MAL219699003E3 TM 196 HVC ENYCAP - MINI CHARGER AND BACKUP BOARD DESCRIPTION The MAL219699003E3 mini charger and backup demonstration circuit is a fully transparent charger unit that uses a BQ24095 charging IC and TPS610997 boost converter IC from Texas Instruments to boost the capacitor voltage up to a 5 V constant output voltage. TM This mini charger is equipped with a 90 F / 4.2 V 196 HVC ENYCAP hybrid energy storage capacitor, which is charged through the power input. This power input is compatible with a USB port. The charged energy is buffered in the 196 HVC capacitor and can be used for backup power. An independent fixed output voltage of 5 V is created from the backup power of the hybrid capacitor by the TPS610997 synchronous boost converter IC, which provides a constant output voltage with very high efficiency. STORAGE Boost Charger converter V V V V supply charge capacitor backup BQ24095 TPS610997 TM ENYCAP Energy storage capacitor Fig. 1 - Typical block diagram for a backup application and fixed output supply. The storage element is charged through a USB socket V . The constant output voltage V is provided independently from V by the boost converter. supply backup supply Alternatively, the path V can be used capacitor ENERGY STORAGE CAPACITOR A 90 F / 4.2 V 196 HVC ENYCAP hybrid energy storage capacitor is used as an energy buffer in the MAL219690111E3 mini charger, and will provide a fixed output voltage supply with its backup function. The backup time provided by the capacitor depends mainly on the backup current and is indicated in Fig. 2. In the proposed configuration, minutes to hours are achievable. Revision: 22-May-2018 Document Number: 28451 1 For technical questions, contact: hybridstorage vishay.com THIS DOCUMENT IS SUBJECT TO CHANGE WITHOUT NOTICE. THE PRODUCTS DESCRIBED HEREIN AND THIS DOCUMENT ARE SUBJECT TO SPECIFIC DISCLAIMERS, SET FORTH AT www.vishay.com/doc 91000Technical Note www.vishay.com Vishay BCcomponents TM Power Management Solution With 196 HVC ENYCAP for Mini Charger and Fixed Voltage Supply Board Axis Title 6 10 10000 5 10 4 10 1000 3 10 2 10 100 10 C = 90 F (1.4 V to 8.4 V) 1 10 1 10 100 1000 10 000 Discharge Current (mA) Fig. 2 - Typical backup time as a function of discharge current CHARGING IC Texas Instruments BQ24095 is a low cost linear type (LDO) charger with a CC / CV (constant current / constant voltage) mode charging profile of up to 1.25 A. The charging current is adjustable to USB requirements. The charging voltage of the CV mode will be fixed at 4.35 V. The detailing pin assignment is shown in Table 1. The BQ24095 is a highly integrated linear charger device, targeted at space-limited portable applications. The IC operates from either a USB port or AC adapter. The high input voltage range with input overvoltage protection supports low cost unregulated adapters. The BQ24095 has a single power output that charges a backup system. A load can be placed in parallel with the backup capacitor as long as the average system load does not keep the capacitor from charging fully during the 10-hour safety time. TABLE 1 - PIN ASSIGNMENT BQ24095 PIN PIN NAME FUNCTION 1IN Source input Directly connected with a micro USB connector 2 ISET Maximum current setting (CC mode) R5 is assembled with 2 k to GND for a 300 mA limit 3 VSS Connected to GND 4 PRETERM Maximum current setting (CV mode) 1 k to GND for a 50 mA limit on CV mode charging 5 PG LED indicator for input voltage ON: input voltage is normal (4.45 V ~ 6.45 V) OFF: UVLO or input voltage is abnormal 6NC Leave it floating 7 ISET2 Total current limit Connected to GND, means it follows ISET 8 CHG LED indicator for charging state ON: charging OFF: not charging 9TS Temp sensor Function disabled, 10 k to GND 10 OUT Output of linear charger, directly connected to 196 HVC 4.35 V fixed voltage feedback and regulated Revision: 22-May-2018 Document Number: 28451 2 For technical questions, contact: hybridstorage vishay.com THIS DOCUMENT IS SUBJECT TO CHANGE WITHOUT NOTICE. THE PRODUCTS DESCRIBED HEREIN AND THIS DOCUMENT ARE SUBJECT TO SPECIFIC DISCLAIMERS, SET FORTH AT www.vishay.com/doc 91000 TECHNICAL NOTE 2nd line Backup Time (s) 1st line 2nd line