LTC2997 datasheet(6/18 Pages) LINER

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LTC2997

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 VCC, the LTC2997 measures

the internal sensor temperature. Tie D+ to VCC 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.

VCC: Supply Voltage. Bypass this pin to GND with a 0.1μF

(or greater) capacitor. VCC operating range is 2.5V to 5.5V.

VPTAT: VPTAT Voltage Output. The voltage on this pin is

proportional to the sensor’s absolute temperature. VPTAT

can drive a capacitive load of up to 1000pF. For larger

load capacitance, insert 1kΩ between VPTAT and load to

guarantee stability. VPTAT can drive up to ±200μA of load

current. VPTAT is pulled low when the supply voltage goes

below the under voltage lockout threshold.

VREF: Voltage Reference Output. VREF provides a 1.8V

reference voltage. VREF can drive a capacitive load of up

to 1000pF. For larger load capacitance, insert 1kΩ between

VREF and load to guarantee stability. VREF can drive up to

±200μA of load current. Leave VREF open if unused.

Exposed Pad: Exposed pad may be left open or soldered

to GND for better thermal coupling.

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