ADSP-21469KBCZ-3 Analog Devices Inc, ADSP-21469KBCZ-3 Datasheet - Page 62

• Manufacturer Part Number: ADSP-21469KBCZ-3
• Description: 400MHz SHARC Processor W/5 Mbits Ram
• Manufacturer: Analog Devices Inc
• Series: SHARC®r
• Type: Floating Pointr

Specifications of ADSP-21469KBCZ-3

• Interface: DAI, DPI, EBI/EMI, I²C, SCI, SPI, SSP, UART/USART
• Clock Rate: 400MHz
• Non-volatile Memory: External
• On-chip Ram: 5Mb
• Voltage - I/o: 3.30V
• Voltage - Core: 1.05V
• Operating Temperature: -40°C ~ 85°C
• Mounting Type: Surface Mount
• Package / Case: 324-BGA, 324-CSP
• Package: 324CSP-BGA
• Numeric And Arithmetic Format: Floating-Point
• Maximum Speed: 400 MHz
• Ram Size: 640 KB
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant

ADSP-21469
Values of 
design considerations. Note that the thermal characteristics val-
ues provided in
Table 56. Thermal Characteristics for 324-Lead CSP_BGA
Thermal Diode
The ADSP-21469 processors incorporate thermal diodes to
monitor the die temperature. The thermal diode of is a
grounded collector PNP bipolar junction transistor (BJT). The
THD_P pin is connected to the emitter and the THD_M pin is
connected to the base of the transistor. These pins can be used
by an external temperature sensor (such as ADM 1021A or
LM86, or others) to read the die temperature of the chip.
The technique used by the external temperature sensor is to
measure the change in V
at two different currents. This is shown in the following
equation:
where:
Table 57. Thermal Diode Parameters—Transistor Model
1
2
3
4
5
Parameter







Symbol
I
I
n
R
See the Engineer-to-Engineer Note EE-346.
Analog Devices does not recommend operation of the thermal diode under reverse bias.
Not 100% tested. Specified by design characterization.
The ideality factor, nQ, represents the deviation from ideal diode behavior as exemplified by the diode equation: I
The series resistance (R
FW
E
q = electronic charge, V
JA
JMA
JMA
JC
Q
T
JT
JMT
JMT
4, 5
3, 4
2
JB
V
are provided for package comparison and PCB
BE
Table 56
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
=
n
T
BE
) can be used for more accurate readings as needed.

Parameter
Forward Bias Current
Emitter Current
Transistor Ideality
Series Resistance
= voltage across the diode, k = Boltzmann Constant, and T = absolute temperature (Kelvin).
kT
----- -
q
BE
are modeled values.

when the thermal diode is operated
In(N)
Typical
22.7
20.4
19.5
6.6
0.11
0.19
0.24
Rev. 0 | Page 62 of 72 | June 2010
Unit
°C/W
°C/W
°C/W
°C/W
°C/W
°C/W
°C/W
1
Min
10
10
1.012
0.12
n = multiplication factor close to 1, depending on process
variations
k = Boltzmann’s constant
T = temperature (°C)
q = charge of the electron
N = ratio of the two currents
The two currents are usually in the range of 10 μA to 300 μA for
the common temperature sensor chips available.
Table 57
transistor model. Note that Measured Ideality Factor already
takes into effect variations in beta ().
Typ
1.015
0.2
contains the thermal diode specifications using the
C
= I
S
× (e
qVBE/nqkT
Max
1.017
300
300
0.28
–1), where I
S
= saturation current,
Unit
A
A
