Global Control
Table 3: SCLK Frequency Synthesizer Programmable Values (Sheet 2 of 2)
Frequency Range
fOUT < 2 x fXCLK AND fOUT ≥ fXCLK
fOUT < fXCLK AND fOUT ≥ fXCLK / 2
fOUT < fXCLK/2 AND fOUT ≥ fXCLK / 4
fOUT < fXCLK/4 AND fOUT ≥ fXCLK / 8
fOUT < fXCLK/8 AND fOUT ≥ fXCLK / 16
fOUT < fXCLK/16 AND fOUT ≥ fXCLK / 32
SDIV
2
3
4
5
6
7
ADE3700
MD = INT(fXCLK x (2(6 + NDIV - SDIV)) / fOUT)
PE = INT((215) x (MD + 1 - fXCLK x (2(6 + NDIV - SDIV)) / fOUT))
where fXCLK is the external crystal frequency in MHz (typically 27). The maximum SCLK frequency
generated by this block is fXTAL x 2(2+NDIV).
For the lowest power operation, all clock sources should be set to the “zero” setting and the analog
power disables should be set. In this condition, only the crystal clock domain (XCLK) is running and
blocks in INCLK or DOTCLK domains may not be accessible through the I²C interface.
The following modules can have their clocks disabled to reduce power consumption when the chip
is in steady-state mode: FLK, OSD, PGEN, DFT, and DMEAS. Also, the clock to the TCON can be
disabled for non-Smart Panel applications. Note that the OSD module has a special power bypass
bit that must be enabled when the OSD clock is disabled.
Also, the clock to all I²C registers associated with modules in the INCLK and DOTCLK domains can
be disabled after the chip is configured to reduce power in steady-state mode. Note that during chip
configuration, all I²C clocks must be enabled.
An asynchronous clock enable override signal must be disabled to allow control of individual
module clock signals.
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