TM
Technical Specification
S25-48-3.3, S25-48-3.3N
48Vin 3.3Vout 7A
Start up Information
Scenario #1: Initial Start up from power supply
On/Off function enabled, the unit starts via input
voltage Vin, see Fig 7.
Time
Comments
t0 On/Off pin is On: system front-end power is switched
on, Vin to unit begins to rise.
t1 Vin crosses Under Voltage Lockout protection circuit
threshold: the unit enabled to be on
t2 The unit begins to turn on ( unit turn-on delay).
t3
Unit output voltage reaches 100% of normal
voltage.
For this example, the unit total start up time (t3- t1) is
typically 200us.
Scenario #2: Initial Start up using On/Off Pin
With Vin previously powered, the unit starts via
On/Off pin, see Fig 8.
Fig 7. Start up waveform
Time
t0
Comments
Vin at nominal value.
t1
Arbitrary time when On/Off pin is enabled (Unit
enabled)
t2
t3
End of unit turn-on delay
Unit Vout reaches 100% of nominal voltage.
For this example, the unit total start up time (t3- t1) is
typically 300us.
Fig 8. Start up using On/Off pin
Broadband TelCom Power, Inc. – 1719 S. Grand Avenue, Santa Ana, CA 92705 U.S.A. P 8 of 11
Tel.: 714-259-4888 • Fax: 714-259-0840 • www.btcpower.com • Email: sales@btcpower.com PS S25-48-3.3 Rev 3 16-1-04
BTCPOWER [ BROADBAND TELCOM POWER, INC. ]
