Cirrus Logic CS48DV2B - Manual (Page 11)

CS48DV2B Data Sheet
32-bit Audio DSP for Dedicated Dolby Volume and Audistry by Dolby
DS875F2 Copyright 2009 Cirrus Logic 11
CONFIDENTIAL
CONFIDENTI
A
L
DRA
FT
DELP
HI
5.4 Power Supply Characteristics
(Measurements performed under operating conditions)
5.5 Thermal Data (48-Pin LQFP)
1. Two-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.
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 & ground plane layers.
3. To calculate the die temperature for a given power dissipation
T
j
= Ambient Temperature + [ (Power Dissipation in Watts) *
θ
ja
]
4. To calculate the case temperature for a given power dissipation
T
c
=
T
j
- [ (Power Dissipation in Watts) *
ψ
jt
]
Parameter Min Typ Max Unit
Operational Power Supply Current:
VDD: Core and I/O operating
1
VDDA: PLL operating
VDDIO: With most ports operating
Total Operational Power Dissipation:
Standby Power Supply Current:
VDD: Core and I/O not clocked
VDDA: PLL halted
VDDIO: All connected I/O pins 3-stated by other ICs in system
Total Standby Power Dissipation:
1. Dependent on application firmware and DSP clock speed.
-
-
-
-
-
-
-
203
8
27
480
100
1
50
348
-
-
-
-
-
-
-
mA
mA
mA
mW
μ A
μ A
μ A
μ W
Parameter Symbol Min Typ Max Unit
Junction Temperature T
j
- - 125 °C
Thermal Resistance (Junction to Ambient)
Two-layer Board
1
Four-layer Board
2
θ
ja
-
- 63.5
54
-
-
°C / Watt
Thermal Resistance (Junction to Top of Package)
Two-layer Board 3
Four-layer Board
4
ψ
jt
-
- 0.70
0.64 -
-
°C / Watt