MXB7846
2.375V to 5.25V, 4-Wire Touch-Screen Controller
with Internal Reference and Temperature Sensor
4 _______________________________________________________________________________________
Note 1: Tested at V
DD
= 2.7V.
Note 2: Relative accuracy is the deviation of the analog value at any code from its theoretical value after the full-scale range has
been calibrated.
Note 3: Offset nulled.
Note 4: Conversion time is defined as the number of clock cycles multiplied by the clock period; clock has 50% duty cycle.
Note 5: Resistance measured from the source to drain of the switch.
Note 6: External load should not change during conversion for specified accuracy.
Note 7: ADC performance is limited by the conversion noise floor, typically 300µV
P-P
. An external reference below 2.5V can com-
promise the ADC performance.
Note 8: Difference between Temp0 and Temp1. No calibration necessary.
TIMING CHARACTERISTICS (Figure 1)
(V
DD
= 2.7V to 3.6V, V
REF
= 2.5V, f
DCLK
= 2MHz (50% duty cycle), f
SAMPLE
= 125kHz, 12-bit mode, 0.1µF capacitor at REF, T
A
=
T
MIN
to T
MAX
, unless otherwise noted. Typical values are at T
A
= +25°C.)
