LTM2893/LTM2893-1

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Table 3. Configuration Registers

BIT 7 ADDRESS

(AD7)

BIT 6 (D6) BIT 5 (D5)

BIT 4 (D4)

BIT 3 (D3)

BIT 2 (D2)

BIT 1 (D1)

BIT 0 (D0)

Configuration

address 0

0

OSCDIV2

OSCDIV1

OSCDIV0

CRC enable

0 = disabled

1 = enabled

SC direction

0 = logic-to-iso

1 = Iso-to-logic

SB direction

0 = logic-to-iso

1 = Iso-to-logic

SA direction

0 = logic-to-iso

1 = Iso-to-logic

Configuration

address 1

1

Reserved

0

Reserved

0

DEVICECOUNT1 DEVICECOUNT0 WORDLENGTH2 WORDLENGTH1 WORDLENGTH0

Table 4. SCK2 Frequency Selection Table (Configuration Register 0 Bit 6, 5, 4)

OSCDIV2

(BIT 6)

OSCDIV1

(BIT 5)

OSCDIV0

(BIT 4)

NOMINAL SCK2

FREQUENCY

MINIMUM SCK2

FREQUENCY

LTM2893-1

MINIMUM SCK

FREQUENCY

0

0

0

100MHz

92.5MHz

824kHz

1.185µs

0

0

1

66MHz

61.5MHz

550kHz

1.84µs

0

1

0

50MHz

46.25MHz

412kHz

2.45µs

0

1

1

40MHz

36.5MHz

330kHz

3.08µs

1

0

0

33MHz

30.5MHz

274kHz

3.7µs

1

0

1

25MHz

23.1MHz

206kHz

4.9µs

1

1

0

12.5MHz

11.6MHz

103kHz

9.9µs

1

1

1

6.25MHz

5.8MHz

26kHz

39.0µs

Note: Factory Default Settings are in bold. The LTM2893 may exceed the Minimum SCK Frequency when reading ADC results when SS is low. The CSC

configuration register write requires adherence to the minimum SCK frequency specification.

APPLICATIONS INFORMATION

Table 5. SCK Frequency Selection Timing Specifications

SCK2 FREQUENCY, MAXIMUM

SCK FREQUENCY

LTM2893-1

MIN

MAX

MIN

MAX

MIN

MAX

MIN

MAX

100MHz

10

1185

9.5

10.8

20

1185

20

1185

66MHz

15

1840

14.25

16.2

20

1840

20

1840

50MHz

20

2450

19.0

21.6

20

2450

20

2450

40MHz

25

3080

23.75

27

20

3080

20

3080

33MHz

30

3700

28.0

32.4

20

3700

20

3700

25MHz

40

4900

38.0

43.2

20

4900

20

4900

12.5MHz

80

9900

76.0

86.4

20

9900

20

9900

6.25MHz

160

39000

152.0

172.8

20

39000

20

39000

Table 6. SPI Word Length Selection Table (Configuration Register 1 Bits 2, 1, 0)

BITS PER WORD (WORDLENGTH)

WORDLENGTH2 (BIT 2)

WORDLENGTH1 (BIT 1)

WORDLENGTH0 (BIT 0)

8

0

0

0

12

0

0

1

14

0

1

0

16

0

1

1

18

1

0

0

20

1

0

1

24

1

1

0

32

1

1

1