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Timing characteristics – Rainbow Electronics MAX7473 User Manual

Page 4

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MAX7472/MAX7473

HDTV Anti-Aliasing Filters with Triple-Input Mux

4

_______________________________________________________________________________________

TIMING CHARACTERISTICS

(AV

DD

= +5V ±5%, DV

DD

= 2.7V to 3.6V, T

A

= 0°C to +85°C, unless otherwise noted. Typical values are at T

A

= +25°C.) (Figure 1)

PARAMETER

SYMBOL

CONDITIONS

MIN

TYP

MAX

UNITS

Serial Clock Frequency

f

SCL

0

400

kHz

Bus Free Time Between STOP (P)
and START (S) Conditions

t

BUF

1.3

µs

Hold Time (Repeated) START (Sr)
Condition

t

HD;STA

After this period, the first clock pulse is
generated

0.6

µs

SCL Pulse-Width Low

t

LOW

1.3

µs

SCL Pulse-Width High

t

HIGH

0.6

µs

Setup Time for a Repeated START
(Sr) Condition

t

SU;STA

0.6

µs

Data Hold Time

t

HD;DAT

(Note 5)

0

0.9

µs

Data Setup Time

t

SU;DAT

100

ns

Rise Time of Both SDA and SCL
Signals, Receiving

t

r

0

300

ns

Fall Time of Both SDA and SCL
Signals, Receiving

t

f

0

300

ns

Fall Time of SDA Signal,
Transmitting

t

f

(Note 6)

20 +

0.1C

b

300

ns

Setup Time for STOP (P) Condition

t

SU;STO

0.6

µs

Capacitive Load for Each Bus Line

C

b

400

pF

Pulse Width of Spikes Suppressed
by the Input Filter

t

SP

(Note 7)

0

50

ns

Note 1: The filter passband edge is set to code 255.
Note 2: The filter passband edge is set to code 40.
Note 3: 1H is the total line period, depending on the video standard. For NTSC, this is 63.5µs, for HDTV, the line period is 29.64µs.
Note 4: The clamp level is at the sync tip for signals with sync pulses, and is at the blanking level otherwise.
Note 5: A master device must provide a hold time of at least 300ns for the SDA signal (referred to V

IL

of the SCL signal) to bridge

the undefined region of SCL’s falling edge.

Note 6: C

b

= total capacitance of one bus line in pF. t

R

and t

F

measured between 0.3V

DD

and 0.7V

DD

.

Note 7: Input filters on the SDA and SCL inputs suppress noise spikes less than 50ns.

SDA

SCL

t

r

t

f

S

r

t

SP

t

r

P

S

t

LOW

t

HD;STA

t

HD;DAT

t

SU;STA

t

HIGH

t

SU;DAT

t

HD;STA

t

SU;STO

t

BUF

t

f

S

Figure 1. 2-Wire Serial-Interface Timing Diagram