LATCH

SCLK

SDATI

1

2

3

4

6

7

8

2

3

4

5

6

7

8

OUTB4

SDATO

PREVIOUS WRITE DATA

OUTx

OLD OUTPUT

NEW OUTPUT

5

OUTA4

OUTB3

OUTB2

OUTB1

OUTA3

OUTA2

OUTA1

1

Fault data latched

FLTB4

FLTA4

FLTB3

FLTB2

FLTB1

FLTA3

FLTA2

FLTA1

SCLK

RESET

nFAULT

SDATIN

LATCH

SCLK

RESET

SDATOUT

SDATIN

LATCH

nFAULT

SCLK

RESET

SDATOUT

SDATIN

LATCH

nFAULT

SDATOUT

DRV8806 “A”

DRV8806 “B”

+

+

DRV8806

www.ti.com

SLVSBA3 – JUNE 2012

Daisy-Chain Connection

Two or more DRV8806 devices may be connected together to use a single serial interface. The SDATOUT pin of

the first device in the chain is connected to the SDATIN pin of the next device. The SCLK, LATCH, RESET, and

nFAULT pins are connected together.

Figure 4. Daisy-Chain Connection

Figure 5 shows an example of a serial transaction, writing the output bits, and then reading the fault status bits,

using two devices connected together in a daisy-chain.

Note that the LATCH signal must be high for a minimum of 200 ns before valid data can be clocked out.

Figure 5. Daisy-Chain Serial Transaction

nENBL and RESET Operation

The nENBL pin enables or disables the output drivers. nENBL must be low to enable the outputs. nENBL does

not affect the operation of the serial interface logic. Note that nENBL has an internal pulldown.

The RESET pin, when driven active high, resets internal logic, including the OCP fault. All serial interface

registers are cleared. Note that RESET has an internal pulldown. An internal power-up reset is also provided, so

it is not required to drive RESET at power-up.

Copyright © 2012, Texas Instruments Incorporated

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Product Folder Link(s): DRV8806