CS4953xx Data Sheet

32-bit Audio Decoder DSP Family

DS705PP3

Copyright 2008 Cirrus Logic

11

5.4 Power Supply Characteristics

(measurements performed under operating conditions)

5.5 Thermal Data (144 LQFP)

5.6 Thermal Data (128 LQFP)

of the top & bottom layers.

2.

Four-layer board is specified as a 76 mm X 114 mm, 1.6 mm thick FR-4 material with 1-oz copper covering 20 %

of the top & bottom layers and 0.5-oz copper covering 90 % of the internal power plane and ground plane layers.

3.

To calculate the die temperature for a given power dissipation

4.

Τ

θ

5.

To calculate the case temperature for a given power dissipation

6.

Τ

Τ

5.7 Switching Characteristics— RESET

Parameter

Min

Typ

Max

Unit

Power supply current:

PLL operating: VDDA

With external memory and most ports operating: VDDIO

1. Dependent on application firmware and DSP clock speed.

-

-

-

500

3.5

120

-

-

-

mA

mA

mA

Parameter

Symbol

Min

Typ

Max

Unit

Thermal Resistance (Junction to Ambient)

Two-layer Board1

Four-layer Board2

θ

ja

-

-

48

40

-

-

°C / Watt

Thermal Resistance (Junction to Top of Package)

Two-layer Board1

Four-layer Board2

ψ

jt

-

-

.39

.33

-

-

°C / Watt

Parameter

Symbol

Min

Typ

Max

Unit

Thermal Resistance (Junction to Ambient)

Two-layer Board1

Four-layer Board2

θ

ja

-

-

53

44

-

-

°C / Watt

Thermal Resistance (Junction to Top of Package)

Two-layer Board1

Four-layer Board2

ψ

jt

-

-

.45

.39

-

-

°C / Watt

Parameter

Symbol

Min

Max

Unit

RESET# minimum pulse width low

1-

μs

All bidirectional pins high-Z after RESET# low

-100

ns

Configuration pins setup before RESET# high

50

-

ns

Configuration pins hold after RESET# high

20

-

ns