Datasheet

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PTB78560C ELECTRICAL CHARACTERISTICS
PTB78560A , PTB78560B
PTB78560C
SLTS249 – JUNE 2005
(Unless otherwise stated, T
A
= 25°C, V
I
= 24 V, V
O
= 12 V, C
O
= 100 µF, and I
O
= I
O
max)
PTB78560C
PARAMETER TEST CONDITIONS UNIT
MIN TYP MAX
I
O
Output current Over V
I
range I
O
Bus 0.1
(1)
2.5
(2)
A
V
I
Input voltage range Over I
O
range 18 24 60 V
Set-point voltage tolerance ±1
(3)
%V
O
Temperature variation -40°C ≤ T
A
≤ 85°C ±0.5 %V
O
Line regulation Over V
I
range ±0.2 ±1 %V
O
V
O
Load regulation Over I
O
range ±0.4 ±1 %V
O
Total output voltage variation Includes set-point, line, load, –40°C ≤ T
A
≤ 85°C ±2 ±3
(3)
%V
O
Adjust range Over V
I
range 9 13.2 V
R
SET
= 9.09 k Ω , V
O
=12 V 88%
η Efficiency
R
SET
= open, V
O
= 9 V 86%
V
O
Ripple (peak-to-peak) 20-MHz bandwidth 1 %V
O
0.1 A/µs load step, Recovery time 100 µs
Transient Response 50% to 100%
V
O
over/undershoot ±150 mV
I
O
max
Input current Track connected to -Sense –0.48 mA
Track input (pin 5)
Open-circuit voltage 0 V
O
Bus
Referenced to -V
I
Input high voltage (V
IH
) 2 Open
(4)
V
Output enable inputs (pins 2, 3) Input low voltage (V
IL
) -0.2 0.8
Input low current (I
IL
) –0.8 mA
Standby input current Pins 2 and 3 open 8 16 mA
I
O
Bus Overcurrent threshold Shutdown, followed by autorecovery 3.75 A
V
I
increasing 17
UVLO Undervoltage lockout V
V
I
decreasing 16
ƒ
S
Switching frequency Over V
I
range 400 500 600 kHz
Internal input capacitance 1 µF
External input capacitance Between +V
I
and –V
I
100 µF
External output capacitance Between both outputs and V
O
COM 100 1,500 µF
Isolation voltage Input-output 1,500 Vdc
Isolation capacitance Input-output 2,000 pF
Isolation resistance Input-output 10 M Ω
Telcordia SR-332 50% stress, T
A
= 40°C, ground
MTBF Reliability 3.4 10
6
Hrs
benign
(1) The converter requires a minimum load current for proper operation. The converter is not damaged when operated under a no-load
condition.
(2) See temperature derating curves for safe operating area (SOA), to determine output current derating at elevated ambient temperatures.
(3) The set-point voltage tolerance is affected by the tolerance and stability of R
SET
. The stated limit is unconditionally met if R
SET
has a
tolerance of 1%, with 100 ppm/°C temperature stability.
(4) The PEN and NEN enable inputs each have an internal pullup resistor. If the enable feature is not used, the PEN input (pin 2) should be
left open circuit and the NEN input (pin 3) permanently connected to –V
I
. A discrete MOSFET or bipolar transistor is recommended for
the enable control. The open-circuit voltage is less than 10 V. See the Application Information for a more detailed description.
6
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