Decimation mode, Die junction temperature monitoring function – Rainbow Electronics AT84AD001B User Manual

Page 44

AT84AD001B

2153C–BDC–04/04

Example:

Address = 110

Data =

One should then obtain 01010101 on Port B and 10101010 on Port A.

When the dynamic mode is chosen (Data1 = 1) port B outputs a rising ramp while Port A
outputs a decreasing one.

Note:

In dynamic mode, use the DRDA function to align the edges of CLKO with the middle of
the data.

Decimation Mode

The decimation mode is provided to enable rapid testing of the ADC at a maximum clock
frequency of 750 Msps. In decimation mode, one data out of 16 is output, thus leading to
a maximum output rate of 46.875 Msps.

Note:

Frequency (CLKO) = frequency (Data) = Frequency (CLKI)/16.

Die Junction
Temperature Monitoring
Function

A die junction temperature measurement setting is included on the board for junction
temperature monitoring.

The measurement method forces a 1 mA current into a diode-mounted transistor.

Caution should be given to respecting the polarity of the current.

In any case, one should make sure the maximum voltage compliance of the current
source is limited to a maximum of 1V or use a resistor serial-mounted with the current
source to avoid damaging the transistor device (this may occur if the current source is
reverse-connected).

The measurement setup is illustrated in Figure 47.

Figure 47. Die Junction Temperature Monitoring Setup

D15

D14

D13

D12

D11

D10

1 mA

GNDD

(Pin 36)

VDiode (Pin 35)

Protection

Diodes