MAX106CHC Maxim, MAX106CHC Datasheet - Page 24

• Manufacturer Part Number: MAX106CHC
• Description: 5V / 600Msps / 8-Bit ADC with On-Chip 2.2GHz Bandwidth Track/Hold Amplifier
• Manufacturer: Maxim

determining the die temperature is to measure each
current with an ammeter (which shuts off the internal
catch diodes) referenced to GNDI. The die temperature
in °C is then calculated by the expression:
Another method of determining the die temperature
uses the operational amplifier circuit shown in Figure
20. The circuit produces a voltage that is proportional
to the die temperature. A possible application for this
signal is speed control for a cooling fan to maintain
constant MAX106 die temperature. The circuit operates
by converting the I
ages V
account for their equal values at +27°C. This voltage
difference is then amplified by two amplifiers in an
instrumentation-amplifier configuration with adjustable
gain. The nominal value of the circuit gain is 4.5092V/V.
The gain of the instrumentation amplifier is given by the
expression:
±5V, 600Msps, 8-Bit ADC with On-Chip
2.2GHz Bandwidth Track/Hold Amplifier
24
Figure 20. Die Temperature-Acquisition Circuit with the MAX479
I
______________________________________________________________________________________
CONST
I
PTAT
CONST
6.65k
T
DIE
A
A
and V
V
V
300
CONST
PTAT
1
V
6.65k
1/4 MAX479
CONST
I
CONST
I
PTAT
R
R
, with appropriate scaling to
2
V
1
and I
TEMP
6.05k
2
V
R
PTAT
R
PTAT
273
1
3
12.1k
12.1k
currents to volt-
1/4 MAX479
2
JU1
1
3
V
PTAT
7.5k
To calibrate the circuit, first connect pins 2-3 on JU1 to
zero the input of the PTAT path. With the MAX106 pow-
ered up, adjust potentiometer R3 until the voltage at the
V
restores normal operation to the circuit after the calibra-
tion is complete. The voltage at the V
then be proportional to the actual MAX106 die tempera-
ture according to the equation:
The overall accuracy of the die temperature measure-
ment using the operational-amplifier scaling circuitry is
limited mainly by the accuracy and matching of the
resistors in the circuit.
Depending on the application environment for the
ESBGA-packaged MAX106, the customer may have to
apply an external heatsink to the package after board
assembly. Existing open-tooled heatsinks are available
from standard heatsink suppliers (listed in Heatsink
Manufacturers ). The heatsinks are available with preap-
plied adhesive for easy package mounting.
R1
TEMP
V
CONST
output is -2.728V. Connecting pins 1-2 on JU1
3.32k
15k
R2
1/4 MAX479
T
DIE
( C)
5k
15k
R2
10-TURN
100 V
Thermal Management
TEMP
7.5k
R1
1/4 MAX479
TEMP
V
TEMP
node will