beautypg.com

Timing characteristics – Rainbow Electronics MAX3420E User Manual

Page 10

background image

MAX3420E

USB Peripheral Controller
with SPI Interface

10

______________________________________________________________________________________

Note 1: Parameters are 100% production tested at T

A

= +25°C, and guaranteed by correlation over temperature.

Note 2: Design guaranteed by bench testing. Limits are not production tested.
Note 3: At V

L

= 1.71V to 2.5V, derate all of the SPI timing characteristics by 50%. Not production tested.

Note 4: The minimum period is derived from SPI timing parameters.
Note 5: Time-to-exit suspend is dependent on the crystal used.
Note 6: Redesign in progress to meet USB specification.

PARAMETER

SYMBOL

CONDITIONS

MIN

TYP

MAX

UNITS

PARAMETER

SYMBOL

CONDITIONS

MIN

TYP

MAX

UNITS

USB TRANSMITTER TIMING CHARACTERISTICS

D+, D- Rise Time

t

RISE

C

L

= 50pF, Figures 6 and 7

4

20

ns

D+, D- Fall Time

t

FALL

C

L

= 50pF, Figures 6 and 7

4

20

ns

Rise-/Fall-Time Matching

C

L

= 50pF, Figures 6 and 7 (Note 2)

90

110

%

Output-Signal Crossover Voltage

C

L

= 50pF, Figures 6 and 7 (Note 2)

1.3

2.0

V

SPI BUS TIMING CHARACTERISTICS (V

L

= 2.5V, C

SS

= 33pF*) (Figures 8 and 9) (Note 3)

V

L

= 1.71V

77.0

S eri al C l ock ( SC LK) P eri od ( N ote 4)

t

CP

V

L

= 2.5V

38.4

ns

SCLK Pulse-Width High

t

CH

17

ns

SCLK Pulse-Width Low

t

CL

17

ns

SS Fall-to-MISO Valid

t

CSS

20

ns

SS Leading Time Before the First
SCLK Edge

t

L

30

ns

SS Trailing Time After the Last
SCLK Edge

t

T

30

ns

Data-In Setup Time

t

DS

5

ns

Data-In Hold Time

t

DH

10

ns

SS Pulse High

t

CSW

200

ns

SCLK Fall-to-MISO Propagation
Delay

t

DO

14.2

ns

SCLK Fall-to-MOSI Propagation
Delay

t

DI

14.2

ns

SCLK Rise-to-MOSI Drive

t

ON

3.5

ns

SS High-to-MOSI High
Impedance

t

OFF

20

ns

SUSPEND TIMING CHARACTERISTICS

Time-to-Enter Suspend

PWRDOWN = 1 to oscillator stop

5

µs

Time-to-Exit Suspend

PWRDOWN = 1 to 0 to OSCOKIRQ (Note 5)

3

ms

TIMING CHARACTERISTICS

(

V

CC

= +3V to +3.6V, V

L

= +1.71V to +3.6V, T

A

= T

MIN

to T

MAX

, unless otherwise noted. Typical values are at V

CC

= +3.3V, V

L

=

+2.5V, T

A

= +25

°C.) (Note 1

)

*33pF capacitor will not be required after redesign.