Datasheet

TPS40054
TPS40055
TPS40057
www.ti.com SLUS593H –DECEMBER 2003–REVISED JULY 2012
ELECTRICAL CHARACTERISTICS
T
A
= –40°C to 85°C, V
IN
= 24 V
dc
, R
T
= 90.9 kΩ, I
KFF
= 150 µA, f
SW
= 500 kHz, all parameters at zero power dissipation
(unless otherwise noted)
PARAMETER TEST CONDITIONS MIN TYP MAX UNIT
INPUT SUPPLY
V
IN
Input voltage range, VIN 8 40 V
OPERATING CURRENT
I
DD
Quiescent current Output drivers not switching, V
FB
≥ 0.75 V 1.5 3.0 mA
BP5
V
BP5
Output voltage I
O
≤ 1 mA 4.7 5.0 5.2 V
OSCILLATOR/RAMP GENERATOR
f
OSC
Accuracy 8 V ≤ V
IN
≤ 40 V 470 520 570 kHz
V
RAMP
PWM ramp voltage
(1)
V
PEAK
– V
VAL
2.0
V
V
IH
High-level input voltage, SYNC 2
V
IL
Low-level input voltage, SYNC 0.8 V
I
SYNC
Input current, SYNC 5 10 µA
Pulse width, SYNC 50 ns
V
RT
RT voltage 2.38 2.50 2.58 V
V
FB
= 0 V, f
SW
≤ 500 kHz 85% 94%
D
MAX
Maximum duty cycle
V
FB
= 0 V, 500 kHz ≤ f
SW
≤ 1 MHz
(1)
80%
Minumum duty cycle V
FB
≥ 0.75 V 0%
V
KFF
Feed-forward voltage 3.35 3.48 3.65 V
I
KFF
Feed-forward current operating range
(1) (2)
20 1100 µA
SOFT START
I
SS/SD
Soft-start source current 1.65 2.35 2.95 µA
V
SS/SD
Soft-start clamp voltage 3.7 V
t
DSCH
Discharge time C
SS/SD
= 220 pF 1.6 2.2 2.8
µs
t
SS/SD
Soft-start time C
SS/SD
= 220 pF, 0 V ≤ V
SS/SD
≤ 1.6 V 115 150 215
BP10
V
BP10
Output voltage I
O
≤ 1 mA 9.0 9.6 10.3 V
ERROR AMPLIFIER
8 V ≤ V
IN
≤ 40 V, T
A
= 25°C 0.698 0.700 0.704
V
FB
Feedback input voltage 8 V ≤ V
IN
≤ 40 V, 0°C ≤ T
A
≤ 85°C 0.693 0.700 0.707 V
8 V ≤ V
IN
≤ 40 V, -40°C≤ T
A
≤ 85°C 0.693 0.700 0.715
G
BW
Gain bandwidth
(1)
3.0 5.0 MHz
A
VOL
Open loop gain 60 80 dB
I
OH
High-level output source current 2.0 4.0
mA
I
OL
Low-level output sink current 2.0 4.0
V
OH
High-level output voltage I
SOURCE
= 500 µA 3.2 3.5
V
V
OL
Low-level output voltage I
SINK
= 500 µA 0.20 0.35
I
BIAS
Input bias current V
FB
= 0.7 V 100 200 nA
(1) Ensured by design. Not production tested.
(2) I
KFF
increases with SYNC frequency, maximum duty cycle decreases with I
KFF
.
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