rtd UPS25, Руководство пользователя

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UPS25 25
RTD Embedded Technologies, Inc
If top off mode is enabled the charger will pulse charge for a period of 5 seconds
and rest for 30 seconds. This mode will ensure that maximum charging capacity
is reached. For long term maintaining of the charge of the backup battery a
special trickle mode is supported by the UPS25. This state is entered after all
other charge modes are complete. In the trickle mode the battery is charged with
a constant C/36 current if the charger circuitry is powered with a Ni-MH
configured UPS25, in case the UPS25 is set for Ni-Cd batteries the trickle charge
rate is C/16.
Power switching circuitry
The UPS25 features voltage dependent automatic power switching using logic and
power MOSFET transistors. These transistors are controlled based on the voltages
detected by the onboard voltage monitor. The following power switches are included in
the design:
Control method Description
1) Converter sw. Software control Enable the operation of the charge
power step-up DC/DC converter
2) Charge power sw.
BQ2003 control Control the charging of the battery
(No user control over this feature)
3) Backup/Charge sw.
Voltage monitors This switch pair either enables charging,
while the supply is present (>10V), or
enters battery backup mode where no
charging can take place.
4) CPU power sw. Software / Vin This relay switch is connected to the
switched VOS output (see Fig. 3-2). The
relay remains closed while VIN is
present during operation, and
“/sleep”-bit is high while entering
backup. In backup state clearing
/sleep bit the system will disconnect
the backup.