DSP56374UMSLASHD datasheet(29/64 Pages) FREESCALE

29 / 64 page

AC Electrical Characteristics

DSP56374 Data Sheet, Rev. 4.2

Freescale Semiconductor

AC Electrical Characteristics

The timing waveforms shown in the AC electrical characteristics section are tested with a VIL maximum

of 0.8 V and a VIH minimum of 2.0 V for all pins. AC timing specifications, which are referenced to a

device input signal, are measured in production with respect to the 50% point of the respective input

signal’s transition. DSP56374 output levels are measured with the production test machine VOL and VOH

reference levels set at 1.0 V and 1.8 V, respectively.

Internal Clocks

External Clock Operation

The DSP56374 system clock is derived from the on-chip oscillator or is externally supplied. To use the

on-chip oscillator, connect a crystal and associated resistor/capacitor components to EXTAL and XTAL;

an example is shown below.

Table 18. INTERNAL CLOCKS1

No.

Characteristics

Symbol

Min

Typ

Max

Unit

Condition

Comparison Frequency

Fref

—

MHz

Fref = FIN/NR

Input Clock Frequency

FIN

Fref*NR

NR is input divider value

Output clock Frequency (with

PLL enabled)2,3

FOUT

13.3

(Ef

× MF x FM)/

(PDF

× DF x OD)

150

MHz

FOUT=FVCO/NO where

NO is output divider value

Output clock Frequency (with

PLL disabled)2,3

FOUT

—

150

MHz

—

Duty Cycle

—

FVCO=300MHz~600MHz

Note:

1 See users manual for definition.

2 DF = Division Factor

Ef = External Frequency

Mf = Multiplication Factor

PDF = Predivision Factor

FM= Frequency Multiplier

OD = Output Divider

Tc = Internal Clock Period

3 Maximum frequency will vary depending on the ordered part number.

DSP56374UM/D Datasheet(PDF) 29 Page - Freescale Semiconductor, Inc

DSP56374UM/D Datasheet(HTML) 29 Page - Freescale Semiconductor, Inc

Html Pages

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64

Datasheet Download

Link URL