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dc1767f
DEMO MANUAL DC1767
DESCRIPTION
LTC2997
Remote/Internal
Temperature Sensor
Demonstration circuit 1767 features the LTC
®
2997, a high
accuracy, analog output, temperature sensor.
DC1767 is designed to allow easy evaluation of the LTC2997.
L, LT, LTC, LTM, Linear Technology and the Linear logo are registered trademarks of Linear
Technology Corporation. All other trademarks are the property of their respective owners.
Design files for this circuit board are available at
http://www.linear.com/demo
QUICK START PROCEDURE
Jumper Settings
D+/D–: These jumpers select which temperature input con-
nects to the LTC2997. INT uses the internal temperature
sensor, EXT uses an off-board sensor connected to the
D+/D– analog inputs, and Q1 uses the transistor stuffed
in Q1 (the MMBT3904 by default).
Analog Connections
Analog signal connections are made via the row of turret
posts along the edges of the board.
GND: (2 turrets) These turrets connect directly to the
internal ground planes.
VCC: Connect a 2.25V to 5.5V power supply to this turret.
D+/D–: Should be set to EXT. This is where the external
diode should be connected.
VREF: Output Only. 1.8V ouput that can drive up to ±200μA
of load.
VPTAT: The voltage on this turret is proportional to the
sensor’s absolute temperature, with a slope of 4mV/K.
VPTAT can drive up to a ±200μA load and up to 1000pF
capacitive load.
INPUTS
EXTERNAL DIODES
CONNECTED HERE
ANALOG VOLTAGE OUTPUT, 4mV/k
1.8V REFERENCE OUTPUT
Figure 1. Proper Measurement Equipment Setup
