E l e c t r i c a l C h a r a c t e r i s t i c s

Serial internal/external timing

Operating conditions:

Temperature:

-15.00 (min)

110.00 (max)

Voltage:

1.60 (min)

1.40 (max)

Output load:

25.0pf

 

Input drive:

CMOS buffer

 

Note: SPI timing diagrams are in Chapter 10, "Serial Controller Module." See Figure 25, "SPI master mode 0 and 1 two-byte transfer," on page 219 and Figure 26, "SPI slave mode 0 and 1 two-byte transfer," on page 222. Only SPI modes 0 and 1 are supported.

Serial internal timing characteristics

Num

Description

Min

Max

Unit

 

 

 

 

 

76

SCLK to ENABLE high

1

 

TSCLK

77

SCLK to TXD (PORTA7/C7)

 

1 TSYS*

ns

78

RXD (PORTA3/C3) setup to SCLK

1

 

ns

 

 

 

 

 

79

RXD hold to SCLK

1

 

ns

* The TSYS parameter represents one period of the internal system clock.

Serial external timing characteristics

Num

Description

Min

Max

Unit

 

 

 

 

 

80

SCLK frequency

 

10

MHz

 

 

 

 

 

 

SCLK duty cycle

45

55

%

 

 

 

 

 

81

SCLK to ENABLE

1

 

TSCLK

82

SCLK to TXD (PORTA7/C7)

 

2TSYS*

ns

83

RXD (PORTA3/C3) setup to SCLK

2

 

ns

 

 

 

 

 

84

RXD hold to SCLK

1.5

 

ns

* The TSYS parameter represents one period of the internal system clock.

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Digi NS7520 manual Serial internal/external timing, Serial internal timing characteristics, 2T SYS