GX3202 Datasheet, PDF (31/49 Pages) Semtech Corporation – Crosspoint Switch with Trace Equalization and Output De-emphasis

4.8 Temperature Sensors
The GX3202 has twelve on-chip temperature sensors comprised of four junction diode
temperature sensors and four ADCs, each with two selectable temperature sensors.
Analog output voltages can be used to determine the temperature of the chip at the
junction diode temperature sensors in four different locations. An external test current
is applied to each sensor, and the voltage across the sensor is measured.
Note that the “A” and “K” of the pin names indicate the preferred direction of the test
current, but other junctions are present internally. Test currents should be limited to
10mA or less.
DTHERMA[3:0]
DTHERMK[3:0]
Figure 4-3: Temperature Sensors
In addition to the diode temperature sensors, four ADCs, each with two selectable
temperature sensors, are also provided. Digitized temperatures can be read through the
device’s host interface.
thermo
ADC 1 _{Even Outputs 0 to 288}
thermo
ADC 2
Crosspoint Core
Legend:
ADC and “local” temperature sensors
“remote” temperature sensors
thermo
ADC 3
Odd Outputs 1 to 289
thermo
ADC 0
Package Top-view of Die
Figure 4-4: Map of Thermometer ADC Positions on Die
GX3202 202 x 202 3.5Gb/s Crosspoint
Data Sheet
56077 - 1
October 2012
31 of 49
Proprietary & Confidential