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360
Revision 3.0
G
Electrical Specifications
(Continued)
8.1.4.3
Definition of System Conditions for Measur-
ing On Parameters
The SC2200’s current is highly dependent on two func-
tional characteristics, DCLK (DOT clock) and SDRAM fre-
quency. Table 8-4 shows how these factors are controlled
when measuring the typical average and absolute maxi-
mum processor current parameters.
8.1.4.4
Table 8-5 and Table 8-6 show the DC current measure-
ments of the SC2200. The SC2200 supports CRT and TFT
DC Current Measurements
displays, but it is expected that generally only one display
interface will be used. Power consumed by the SC2200 is
different with different displays. The CRT DAC requires cur-
rent, while the TFT interface even though it has no DAC to
power, also draws current while it is active. The CRT DAC
and the TFT interface are presented as separate line items.
The chosen display type I/O current should be added to the
Typical, Absolute Maximum, and Active Idle I/O currents to
get total current.
Table 8-4. System Conditions Used to Measure SC2200’s Current Used During the "On" State
CPU Current Measurement
System Conditions
V
CORE1
V
IO1
DCLK Freq.
SDRAM Freq.
Typical Average
Nominal
Nominal
50 MHz
2
Nominal
Absolute Maximum
Max
Max
135 MHz
3
Max
1.
2.
See Table 8-2 on page 358 for nominal and maximum voltages.
A DCLK frequency of 50 MHz is derived by setting the display mode to 800x600x8 bpp at 75 Hz, using a display image
of vertical stripes (4-pixel wide) alternating between black and white with power management disabled.
A DCLK frequency of 135 MHz is derived by setting the display mode to 1280x1024x8 bpp at 75 Hz, using a display
image of vertical stripes (1-pixel wide) alternating between black and white with power management disabled.
3.
Table 8-5. DC Characteristics On Mode
Symbol
Parameter
1
Typ Avg
Abs Max
Unit
Comments
I
CC3ON
f
CLK
= 233 MHz, I/O Current @ V
IO
= 3.3V
(Nominal); CPU mode = On, excludes TFT
interface contribution and CRT DAC
230
250
mA
I
CC
for V
IO
f
CLK
= 266 MHz, I/O Current @ V
IO
= 3.3V
(Nominal); CPU mode = On, excludes TFT
interface contribution and CRT DAC
240
260
f
CLK
= 300 MHz, I/O Current @ V
IO
= 3.3V
(Nominal); CPU mode = On, excludes TFT
interface contribution and CRT DAC
250
270
I
COREON
f
CLK
= 233 MHz, Core Current @ V
CORE
=
1.8V (Nominal); CPU mode = On
820
990
mA
I
CC
for V
CORE
f
CLK
= 266 MHz, Core Current @ V
CORE
=
1.8V (Nominal); CPU mode = On
900
1090
f
CLK
= 300 MHz, Core Current @ V
CORE
=
2.0V (Nominal); CPU mode = On
1050
1330
I
SBON
SB Current @ V
SB
= 3.3V (Nominal); CPU
mode = On
1
2
mA
I
SBLON
SBL Current @ V
SBL
= 1.8V (Nominal); CPU
mode = On
10
20
mA
SBL Current @ V
SBL
= 2.0V (Nominal); CPU
mode = On
10
20