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AS1123

Datasheet - D e t a i l e d D e s c r i p t i o n

Detailed Error Reports

The detailed error report can be read out after global error mode has been run. At the falling edge of LD, the detailed error report of the selected

test is latched into the shift register and can be clocked out with n*16 clock cycles (n is the number of AS1123s in a chain) via pin SDO. At the

same time new data can be written into the shift register, which is loaded on the next rising edge of pin LD. This pattern is shown at the output

drivers, at the falling edge of OEN.

Detailed Temperature Warning Report

The detailed temperature warning report can be read out immediately after global error mode has been run. SDI must be 1 for the first device.

Bit0 of the 16bit data word represents the temperature flag of the chip.

Figure 14. Detailed Temperature Warning Report Timing Diagram

Detailed Temperature Warning Report Example:

Consider a case where four AS1123s are cascaded in one chain. The detailed error report lists the temperatures for each device in the chain:

IC1:[70°] IC2:[85°] IC3:[170°] IC4:[60°]

In this case, IC3 is overheated and will generate a global error, and therefore 4*16 clock cycles are needed to write out the detailed temperature

warning report, and optionally read in new data. The detailed temperature warning report would look like this:

XXXXXXXXXXXXXXX1 XXXXXXXXXXXXXXX1 XXXXXXXXXXXXXXX0 XXXXXXXXXXXXXXX1

The 0 in the detailed temperature warning report indicates that IC3 is the device with the over-temperature condition.

Note:

In an actual report there are no spaces in the output.

Global Flag Readout

Detailed Error Report Readout

SDI

OEN

LD

CLK

SDO

New Data Input

DBit15

Undefined

Don’t

Care

Don’t

Care

Temperature Error Report Output

DBit14

DBit13 DBit12

DBitn

DBit2

DBit1

DBit0

TBit0

For detailed timing information see Timing Diagrams on page 8.