L9963T-TR datasheet(28/45 Pages) STMICROELECTRONICS

28 / 45 page

Symbol

Parameters

Test conditions

Min

Typ Max Unit

Note

Thcld

SDI input hold time (time

passed after propagating SCK

edge @ SDI data “not valid

anymore” )

FCLK_SPI = 10 MHz

20% of ½ Tclk @ 10 MHz

(Constrained by Slave spec)

Tlag

CLK toggle before NCS = high

FCLK_SPI = 8 MHz

1.51

μs

FCLK_SPI = 4 MHz

1.51

μs

FCLK_SPI = 1 MHz

7.72

μs

FCLK_SPI = 250 kHz

7.72

μs

Tonncs

CLK toggle before NCS = high

FCLK_SPI = 8 MHz

1.44

μs

FCLK_SPI = 4 MHz

1.44

μs

FCLK_SPI = 1 MHz

5.72

μs

FCLK_SPI = 250 kHz

5.72

μs

Tpchdz

NCS L/H to SDO high

impedance

Cload = 30 pF Valid for

SDO

<< Tonncs

Tcsdv

NCS H/L to SDO active

Cload = 30 pF Valid for

SDO

75% of Tlead important when

CPHA=0

3.4.4

Isolated Serial Peripheral Interface

The Isolated SPI interface allows units with different ground levels and/or on different boards to communicate with

each other. Physically the interface is based on twisted-pair wire.

The isolated SPI pinout is listed in the following tables:

Table 22. L9963T pins used as isolated SPI

L9963T Pin

SPI function

Configuration

ISOP

positive differential input/output

Analog Input/Output

ISOM

negative differential input/output

Analog Input/Output

Table 23. Isolated SPI quick look

Parameter

Description

Protocol

Half-Duplex / Out of frame

Max. Bit-rate

2.66 Mbps (high speed configuration, ISOFREQ = 1)

333 kbps (low speed configuration, ISOFREQ = 0, default if pin is left floating)

The transmission line on the isolated SPI exploits a single twisted pair. Communication data is transmitted/

received over a pulse-shaped signal, in a half-duplex protocol.

Line bit rate can be selected by programming the ISOFREQ device pin.

A single bit is made of a pulse time (TPULSE) followed by two pause slices (2TPULSE):

•

TPULSE = 2TBIT_HIGH_LOW_FAST for the high speed configuration (ISOFREQ = 1)

•

TPULSE = 2TBIT_HIGH_LOW_SLOW for the low speed configuration (ISOFREQ = 0)

L9963T

Serial communication interface

DS13590 - Rev 4

page 28/45

L9963T-TR Scheda tecnica(PDF) 28 Page - STMicroelectronics

L9963T-TR Scheda tecnica(HTML) 28 Page - STMicroelectronics

Html Pages

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45

Scheda tecnica Scarica

Link URL