tb62802fg TOSHIBA Semiconductor CORPORATION, tb62802fg Datasheet - Page 7

• Manufacturer Part Number: tb62802fg
• Description: Ccd Clock Drivers
• Manufacturer: TOSHIBA Semiconductor CORPORATION

Reference Characteristics
Thermal Design
The junction temperature is expressed as follows:
T
T
Ta: Ambient temperature
θjc: Thermal resistance from chip to case (a specific value not affected by environment)
θja: Thermal resistance from chip to ambient temperature (affected by environment)
Pd: Power dissipation when driving external load
should be so designed that the calculated value is within the specified range.
j
j
: Junction temperature
Here, the thermal performance of the heat dispersion on the PCB and of the ambient temperature setting
= Ta + ( θ jc + θ ca) × Pd
= Ta + θ ja × Pd
1.00
0.90
0.80
0.70
0.60
0.50
0.40
0.30
0.20
0.10
0.00
1.2
0.8
0.6
0.4
0.2
1
0
1.0
0
Condition:
(1) Power dissipation
IC internal equivalent capacitance
CCD input capacitance
Driver supply voltage = 5.0 V
Driver output amplitude = 5.0 V
The main clock and control clock oscillate at
the same frequency.
20
3.0
40
Power Dissipation and Junction Temperature (reference value)
60
5.0
80
Load Capacitance vs. Power Dissipation
7.0
100
Heavy load = 57 pF
Light load = 18 pF
Main clock = 250 pF
Control clock = 20 pF
120 140 160 180 200
9.0
Load capacitance pF
Drive frequency MHz
11.0
13.0
(2) Junction temperature
Ta = 25°C
θ ja = 83.3°C/W
(typical value for the IC itself)
7
15.0
Drive frequency: 25 MHz
Supply voltage: 5.0 V
Light load capacitance: 20 pF
Light load internal equivalent capacitance:
Heavy load internal equivalent capacitance:
Ambient temperature: 25°C
18 pF
57 pF
220 240 260 280 300
(all bits are driven at the same frequency)
17.0
19.0
Power dissipation
Junction temperature
21.0
23.0
25.0
120
100
80
60
40
20
0
TB62802FG
2006-06-14