Datasheet

2
UCC1972/3
UCC2972/3
UCC3972/3
TSSOP-8 (TOP VIEW)
PW Package
ABSOLUTE MAXIMUM RATINGS
VBAT .........................................+27V
VDD Maximum Forced Current ....................30mA
Maximum Forced Voltage ..........................17V
BUCK .................................. 5VtoVBAT
MODE .................................–0.3V to 4.0V
MODE Maximum Forced Current ..................300mA
Operating Junction Temperature ..........–55°C to +150°C
Storage Temperature ...................–65°C to +150°C
Unless otherwise indicated, currents are positive into, negative
out of the specified terminal. Pulse is defined as less than 10%
duty cycle with a maximum duration of 500ms. Consult Pack
-
aging Section of Databook for thermal limitations and consider
-
ations of packages. All voltages are referenced to GND.
GND
OUT
VDD
MODE
VBAT
BUCK
COMP
FB
1
2
3
4
8
7
6
5
CONNECTION DIAGRAMS
ELECTRICAL CHARACTERISTICS:
Unless otherwise specified these specifications hold for T
A
=0°C to +70°C for the
UC3972/3, –40°C to +85°C for the UC2972/3, and –55°C to +125°C for the UC1972/3; T
A
=T
J
; VDD=VBAT=VBUCK=12V;
MODE=OPEN. For any tests with VBAT>17V, place a 1k resistor from VBAT to VDD.
PARAMETER TEST CONDITIONS MIN TYP MAX UNITS
Input supply
VDD Supply Current VDD = 12V 1 1.5 mA
VBAT = 25V 7 10.5 mA
VBAT Supply Current VBAT = 12V 30 60
mA
VBAT = 25V 70 140 mA
VDD Regulator Turn-on Voltage I
SOURCE
= 2mA to 10mA 17 18 19 V
VDD UVLO Threshold Low to high 3.6 4 4.4 V
UVLO Threshold Hysteresis 100 200 300 mV
Output Section
Pull Down Resistance I
SINK
= 10mA to 100mA 25 50 W
Pull Up Resistance I
SOURCE
= 10mA to 100mA 25 50 W
Output Clamp Voltage VBAT = 25V, Shunt Regulator on 16 18 V
Output Low MODE = 0.5V, I
SINK
= 1mA 0.05 0.2 V
Rise Time CL = 1nF, Note 1 200 ns
Fall Time CL = 1nF, Note 1 200 ns
FB
MODE
GND
COMP
VDD
OUT
BUCK
VBAT
1
2
3
4
8
7
6
5
DIL-8 (TOP VIEW)
J, N Packages