The following specification apply for V+ = +3.0 V

T

specification revision 0.98. Please refer to that speciation for further details.

Symbol

Parameter

Conditions

Typical

(Note 7)

Limits

(Note 8)

Units

(Limits)

t

r

SWD rise time (Note 16)

R

C

1000

ns (max)

t

INACT

Minimum inactive time (bus at high level)

guaranteed by the slave before an attention

request

11

µs (min)

t

Mtr0

Master drive for Data Bit 0 write and for Data

Bit 0-1read

11.8

µs (min)

17.0

µs (max)

t

Mtr1

Master drive for Data Bit 1 write

35.4

µs (min)

48.9

µs (max)

t

SFEdet

Time allowed for LM40 activity detection

9.6

µs (max)

t

SLout1

LM40 drive for Data Bit 1 read by master

28.3

µs (min)

38.3

µs (max)

t

MtrS

Master drive for Start Bit

80

µs (min)

109

µs (max)

t

SLoutA

LM40 drive for Attention Request

165

µs (min)

228

µs (max)

t

RST

Master or LM40 drive for Reset

354

µs (min)

t

RST_MAX

Maximum drive of SWD by an LM40, after the

power supply is raised above 3V

500

ms (max)

Note 1: Absolute Maximum Ratings indicate limits beyond which damage to the device may occur. Operating Ratings indicate conditions for which the device is

functional, but do not guarantee performance limits. For guaranteed specifications and test conditions, see the Electrical Characteristics. The guaranteed

specifications apply only for the test conditions listed. Some performance characteristics may degrade when the device is not operated under the listed test

conditions.

Note 2: All voltages are measured with respect to GND, unless otherwise noted.

components and/or ESD protection circuitry are shown below for the LM40’s pins. The nominal breakdown voltage of the zener is 6.5 V. SNP stands for snap-back

device.

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