Datasheet

UCD7230
SLUS741D –NOVEMBER 2006–REVISED JANUARY 2010 www.ti.com
ELECTRICAL CHARACTERISTICS
V
DD
= P
VDD
= 12 V, 4.7-mF from V
DD
to A
GND
, 1 mF from P
VDD
to P
GND
, 0.1 mF from CSBIAS to AGND, 0.22 mF from BST to
SW, T
A
= T
J
= -40°C to +125°C, R
CS+
= 5 kΩ, R
DLY
= 50 kΩ over operating free-air temperature range (unless otherwise
noted).
PARAMETER TEST CONDITIONS MIN TYP MAX UNIT
SUPPLY
Supply current, off V
DD
= 4.2 V 500 700 mA
Supply current Outputs not switching IN = LOW 5 8 mA
LOW-VOLTAGE UNDER-VOLTAGE LOCKOUT
VDD UVLO ON V
DD
rising 4.25 4.50 4.75
V
VDD UVLO OFF V
DD
falling 4.00 4.25 4.50
VDD UVLO hysteresis 100 250 400 mV
REFERENCE / EXTERNAL BIAS SUPPLY
3V3 initial set point T
A
= 25°C 3.267 3.3 3.333
V
3V3 over temperature 3.234 3.3 3.366
3V3 load regulation I
LOAD
= 1 mA to 10 mA, V
DD
= 5V 1 7
mV
3V3 line regulation V
DD
= 4.75 V to 12 V, I
LOAD
= 10 mA 3 10
Short circuit current V
DD
= 4.75 V to 12 V 11 20 mA
3V3 OK threshold, ON 3.3 V rising 2.8 3 3.2
V
3V3 OK threshold, OFF 3.3 V falling 2.6 2.8 3.0
INPUT SIGNAL (IN)
Positive-going input threshold
INHigh 1.6 1.9 2.2
voltage
Negative-going input threshold
INLow 1.0 1.3 1.6 V
voltage
INHigh –
Input voltage hysteresis 0.4 0.6 0.8
INLow
Input resistance to AGND 50 100 150 kΩ
Frequency ceiling 2 MHz
CURRENT LIMIT (ILIM)
ILIM internal voltage setpoint I
LIM
=OPEN 0.47 0.50 0.53 V
ILIM input impedance 20 42 65 kΩ
CLF output high level I
LOAD
= 4 mA 2.7
V
CLF output low level I
LOAD
= 4 mA 0.6
Propagation delay from IN to reset 2nd IN rising to CLF falling after a
15 35 ns
CLF current limit event
CURRENT SENSE COMPARATOR (OUTPUT SENSE)
I
LIM
= open 40 50 60
I
LIM
= 3.3 V 80 100 120
CS threshold (POS - NEG) mV
I
LIM
= 0.75 V 60 75 90
I
LIM
= 0.25 V 15 25 35
Propagation delay from POS to
I
LIM
= open, CS = threshold + 60 mV 90
OUT1 falling
(1)
ns
Propagation delay from POS to
I
LIM
= open, CS = threshold + 60 mV 100
CLF
(1)
(1) As designed and characterized. Not 100% tested in production.
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