User manual

Quick Start Instructions

1.3.3 Trouble Shooting: If the device does not acknowledge the

commands

If the device is powered up initially with unstable V

from the PICKit Serial, there is a

chance that the device can latch a wrong address bits from the external address pins,

and therefore it may not acknowledge the command bytes correctly since the address

bits are not matched. In this case, send a General Call Latch Command after the V

is stabilized (after about 20 seconds the PICKit Serial is powered). See the example in

Figure 1-13. Another method is power-up the PICKit Serial first by connecting to the

PC, then insert the MCP3423 EV board to the PICKit Serial about 20 seconds later.

FIGURE 1-13: Examples when the device is not acknowledging the write command. Send the

General Call Latch Command when the V

is stabilized.

NAK Pulse

ACK Pulse

(a) The device

does not

acknowledge the

write command.

(b) Send a

General Call

Latch Command.

now acknowledge

the command.