Datasheet
CY8C20xx6A/H CapSense Design Guide Doc. No. 001-65973 Rev. *A 30
4.2.1.1 Measure iDAC Gain
After following the steps to create a new PSoC Designer Project, use the following code snippet to route iDAC to port
pin P1[0]:
//configure P1[0] to HI-Z
PRT1DM0 &= ~0x01;
PRT1DM1 |= 0x01;
//connect P1[0] to analog mux bus
MUX_CR1 |= 0x01;
// set iDAC to full scale
IDAC_D = 0xFF;
// turn iDAC on, 4x range
CS_CR2 = 0x90;
Place a current meter between pin P1[0] and ground, and measure current, I
MEASURED
=
Equation 8
. Calculate the iDAC gain using
Equation 8.
4.2.1.2 Read SA Code
iDAC code found in the successive approximation is termed as SA code. SA codes computed by CSA_EMC
algorithm for each sensor can be read from array CSA_EMCbaDACCodeBaseline.
4.2.1.3 Estimate C
C
P
P
=
_
Equation 9
can be estimated by using an LCR meter or by applying the following equations.
=
×
×
×
Equation 10
Where:
V
ref
4.2.1.4 Estimate Settling Time
= 1.2 V
The minimum Settling Time is estimated using Equation 11.
,
=
×
×
×
×
Equation 11
Where:
V
ref
= 1.2 V