Datasheet
PTH08T230W, PTH08T231W
SLTS265L –NOVEMBER 2005– REVISED AUGUST 2011
www.ti.com
ELECTRICAL CHARACTERISTICS (continued)
T
A
=25°C, V
I
= 5V, V
O
= 3.3V, C
I
= 330µF, C
O
1 = 200µF ceramic, C
O
2 = 100µF, I
O
= I
O
max (unless otherwise stated)
PARAMETER TEST CONDITIONS PTH08T230W
MIN TYP MAX UNIT
f
SYNC
Synchronization (SYNC) frequency 240 400 kHz
V
SYNCH
SYNC High-Level Input Voltage 2 5.5 V
SmartSync Control
V
SYNCL
SYNC Low-Level Input Voltage 0.8 V
t
SYNC
SYNC Minimum Pulse Width 200 nSec
C
I
External input capacitance 330
(7)
µF
Nonceramic 0
(8)
100 5000
(9)
Capacitance value µF
without
Ceramic 200
(8)
500
TurboTrans
Equivalent series resistance (non-ceramic) 7 mΩ
C
O
External output capacitance
see table 10,000
Capacitance value μF
with
(10) (11)
Turbotrans
Capacitance × ESR product (C
O
× ESR) 1000 10,000 μF×mΩ
Per Telcordia SR-332, 50% stress,
MTBF Reliability 6.7
10
6
Hr
T
A
= 40°C, ground benign
(7) A 330 µF electrolytic input capacitor is required for proper operation. The capacitor must be rated for a minimum of 450 mA rms of ripple
current. An additional 22-μF ceramic input capacitor is recommended to reduce rms ripple current. When operating at V
I
> 8V, the
minimum required C
I
may be reduced to a 220-μF electrolytic plus a 22-μF ceramic.
(8) 200 µF ceramic external output capacitance is required for basic operation. The required ceramic output capacitance can be made up of
2 × 100 µF or 4 × 47 µF. The minimum output capacitance requirement increases when TurboTrans™ (TT) technology is used. See the
Application Information for more guidance.
(9) This is the calculated maximum disregarding TurboTrans™ technology. When the TurboTrans feature is used, the minimum output
capacitance must be increased. See the TurboTrans application notes for further guidance.
(10) When using TurboTrans™ technology, a minimum value of output capacitance is required for proper operation. Additionally, low ESR
capacitors are required for proper operation. See the TurboTrans application notes for further guidance.
(11) This is the calaculated maximum when using the TurboTrans feature. Additionally, low ESR capacitors are required for proper operation.
See the TurboTrans application notes for further guidance.
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