ADSP-21477 View Datasheet(PDF) - Analog Devices
Part Name
Description
MFG CO.
'ADSP-21477' PDF : 76 Pages View PDF
ADSP-21477/ADSP-21478/ADSP-21479
14
TYPE A DRIVE FALL
12
y = 0.0748x + 0.4601
TYPE A DRIVE RISE
10
y = 0.0567x + 0.482
TYPE B DRIVE FALL
8
y = 0.0367x + 0.4502
6
TYPE B DRIVE RISE
4
y = 0.0314x + 0.5729
2
0
0
25
50
75
100
125 150 175 200
LOAD CAPACITANCE (pF)
Figure 51. Typical Output Rise/Fall Time (20% to 80%,
VDD_EXT = Min)
4.5
TYPE A DRIVE FALL
y = 0.0199x + 1.1083
4
TYPE A DRIVE RISE
y = 0.015x + 1.4889
3.5
3
TYPE B DRIVE RISE
y = 0.0088x + 1.6008
2.5
2
TYPE B DRIVE FALL
y = 0.0102x + 1.2726
1.5
1
0.5
0
0
25
50
75
100
125 150 175 200
LOAD CAPACITANCE (pF)
Figure 52. Typical Output Delay or Hold vs. Load Capacitance
(at Ambient Temperature)
THERMAL CHARACTERISTICS
The processor is rated for performance over the temperature
range specified in Operating Conditions on Page 21.
Table 58 airflow measurements comply with JEDEC standards
JESD51-2 and JESD51-6 and the junction-to-board measure-
ment complies with JESD51-8. Test board design complies with
JEDEC standards JESD51-7 (PBGA). The junction-to-case mea-
surement complies with MIL- STD-883. All measurements use a
2S2P JEDEC test board.
To determine the junction temperature of the device while on
the application PCB, use:
TJ = TCASE + JT PD
where:
TJ = junction temperature (°C)
TCASE = case temperature (°C) measured at the top center of the
package
JT = junction-to-top (of package) characterization parameter is
the typical value from Table 58
PD = power dissipation
Values of θJA are provided for package comparison and PCB
design considerations. θJA can be used for a first order approxi-
mation of TJ by the equation:
TJ = TA + JA PD
where:
TA = ambient temperature °C
Values of θJC are provided for package comparison and PCB
design considerations when an external heatsink is required.
Note that the thermal characteristics values provided in
Table 58 are modeled values.
Table 57. Thermal Characteristics for 88-Lead LFCSP_VQ
Parameter
JA
JMA
JMA
JC
JT
JMT
JMT
Condition
Airflow = 0 m/s
Airflow = 1 m/s
Airflow = 2 m/s
Airflow = 0 m/s
Airflow = 1 m/s
Airflow = 2 m/s
Typical
22.6
18.2
17.3
7.9
0.22
0.36
0.44
Unit
°C/W
°C/W
°C/W
°C/W
°C/W
°C/W
°C/W
Table 58. Thermal Characteristics for 100-Lead LQFP_EP
Parameter
θJA
θJMA
θJMA
θJC
ΨJT
ΨJMT
ΨJMT
Condition
Airflow = 0 m/s
Airflow = 1 m/s
Airflow = 2 m/s
Airflow = 0 m/s
Airflow = 1 m/s
Airflow = 2 m/s
Typical
18.1
15.5
14.6
2.4
0.22
0.36
0.50
Unit
°C/W
°C/W
°C/W
°C/W
°C/W
°C/W
°C/W
Table 59. Thermal Characteristics for 196-Ball CSP_BGA
Parameter
θJA
θJMA
θJMA
θJC
ΨJT
ΨJMT
ΨJMT
Condition
Airflow = 0 m/s
Airflow = 1 m/s
Airflow = 2 m/s
Airflow = 0 m/s
Airflow = 1 m/s
Airflow = 2 m/s
Typical
29.0
26.1
25.1
8.8
0.23
0.42
0.52
Unit
°C/W
°C/W
°C/W
°C/W
°C/W
°C/W
°C/W
Rev. C | Page 66 of 76 | July 2013
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