 2004 Microchip Technology Inc.

Preliminary

DS21894B-page 23

MCP2122

FIGURE 4-7:

16XCLK AND THE TX AND TXIR WAVEFORMS

TABLE 4-7:

TX AND TXIR REQUIREMENTS

AC Characteristics

Standard Operating Conditions (unless otherwise specified)

Operating Temperature: –40

Section 4.1 “DC Characteristics”.

Param.

No.

Symbol

Characteristic

Min

Max

Units Conditions

IR113

TX pin rise time and fall time

—

—

25

ns

Note 2

IR114

TX to 16XCLK jitter

—

—

1

↓) to

TXIR rising edge (

7—

8

Smaller of

Smaller of

IR121A

3

—

3

IR121B

1.41

3.5

5

µs

At 9600 baud (Note 3)

IR122

TXIR bit period

—

16

—

20C

TXIR pin rise time

—

10

25

ns

≥ 2.7V (Note 2)

20D

—

10

60

ns

21C

TXIR pin fall time

—

10

25

ns

Note 2

Note 1: Data in the Typical (“Typ”) column is at 5V, +25

°C, unless otherwise stated. These parameters are for

design guidance only and are not tested.

2: These parameters (shaded) are characterized but are not tested. These values should be used for design

guidance only.

3: This specification is not tested. This value is from the design target

16XCLK

01

Data bit x

Data bit x+1

16 CLK

16 CLK

Bit Value

to TX

IR121A

6 CLK

TXIRI (3 * 16XCLK pulses)

IR113

IR122

IR113

IR114

IR115

TXIR Time Out

IR121C

TXIR pin

IR124

IR123

IR121B