MCP795W10-I/SL Microchip Technology, MCP795W10-I/SL Datasheet - Page 29

• Manufacturer Part Number: MCP795W10-I/SL
• Description: SPI GPP RTCC, 1Kb EE, 64B SRAM, WD Timer, Event Detect, ID 14 SOIC .150in TUBE
• Manufacturer: Microchip Technology

In the case where the MSB of the Calibration register
is set to ‘1’, the CLKOUT output waveforms that
appear when bits RS1 and RS0 are set to ‘01’ or ‘10’
are not as responsive to the setting of the Calibration
register. For example, when outputting the 4.096 kHz
waveform (RS1, RS0 set to ‘01’), the output waveform
is generated using only eight input clock cycles.
Consequently, attempting to subtract more than eight
input clock cycles from this output does not have a
meaningful affect on the resulting waveform. Any
affect on the output will appear as a modification in
both the frequency and duty cycle of the waveform
appearing on the CLKOUT output pin.
FIGURE 9-1:
 2011-2012 Microchip Technology Inc.
CLKOUT WAVEFORM
MCP795WXX/MCP795BXX
Preliminary
Delay
Method 2. RS2 bit set to ‘1’
With the RS2 bit set to ‘1’, the following internal timing
signal is output on the CLKOUT pin:
The frequency listed in the table presumes an input
clock source of exactly 32.768 kHz. In terms of the
equivalent number of input clock cycles, the table
becomes:
Unlike
calibration setting is continuously applied and affects
every cycle of the output waveform. This results in the
modulation of the frequency of the output waveform
based upon the setting of the Calibration register.
Using this setting, the calibration function can be
expressed as:
Since the calibration is done every cycle, the frequency
of the output CLKOUT waveform is constant.
where:
RS2
RS2
CALREG
1
1
T
T
T
output
output
input
the
RS1
RS1
x
x
method
=
=
=
=
(32768 +/- (2 * CALREG)) T
clock period of CLKOUT output
signal
clock period of input signal
decimal value of Calibration
register setting and the sign is
determined by the CALSGN bit.
RS0
RS0
x
x
previously
Output Signal
Output Signal
DS22280B-page 29
described,
1.0 Hz
32768
input
the