Datasheet

LTC2997
6
2997fa
PIN FUNCTIONS
D
+
: Diode Sense Current Source. D
+
sources the remote
diode sensing current. Connect D
+
to the anode of the re-
mote sensor device. It is recommended to connect a 470pF
bypass capacitor between D
+
and D
–
. Larger capacitors
may cause settling time errors (see Typical Performance
Characteristics). If D
+
is tied to V
CC
, the LTC2997 measures
the internal sensor temperature. Tie D
+
to V
CC
if unused.
D
–
: Diode Sense Current Sink. Connect D
–
to the cathode
of the remote sensor device. Tie D
–
to GND for single
wire remote sensing (see Typical Applications) or internal
temperature sensing.
GND: Device Ground.
V
CC
: Supply Voltage. Bypass this pin to GND with a 0.1F
(or greater) capacitor. V
CC
operating range is 2.5V to 5.5V.
V
PTAT
: V
PTAT
Voltage Output. The voltage on this pin is
proportional to the sensor’s absolute temperature. V
PTAT
can drive a capacitive load of up to 1000pF. For larger
load capacitance, insert 1k between V
PTAT
and load to
guarantee stability. V
PTAT
can drive up to ±200µA of load
current. V
PTAT
is pulled low when the supply voltage goes
below the under voltage lockout threshold.
V
REF
: Voltage Reference Output. V
REF
provides a 1.8V
reference voltage. V
REF
can drive a capacitive load of up
to 1000pF. For larger load capacitance, insert 1k between
V
REF
and load to guarantee stability. V
REF
can drive up to
±200µA of load current. Leave V
REF
open if unused.
Exposed Pad: Exposed pad may be left open or soldered
to GND for better thermal coupling.