MAX1441GUP/V+ Maxim Integrated Products, MAX1441GUP/V+ Datasheet - Page 9

• Manufacturer Part Number: MAX1441GUP/V+
• Description: Touch Screen Converters & Controllers PROXIMITY SENSR el Proximity and Tou
• Manufacturer: Maxim Integrated Products

Specifications of MAX1441GUP/V+

• Lead Free Status / RoHS Status: Lead free / RoHS Compliant

Figure 2. Capacitive-Sensing Function
the microcontroller can use the OUT1 or OUT2 pins to
signal the event to external modules. The GPIOs can
also provide system or configuration inputs to the micro-
controller.
The device has a power-saving standby mode for
power-sensitive applications. In the standby mode, the
microcontroller is powered down (CPU stop mode) and
the analog front-end runs conversions at a reduced
and programmable rate. A programmable hardware
discriminator monitors the C2D converters outputs and
brings the device out of standby mode when a potential
object-proximity event is detected. The microcontroller
can then analyze the capacitance data and validate the
object-proximity event.
The on-chip watchdog timer requires periodic servicing
from the microcontroller to ensure proper and continuous
operation. The watchdog timer resets the microcontroller
if it is not serviced. This prevents the microcontroller
from permanently hanging up due to unpredicted code
behavior.
The device features an on-chip voltage regulator allowing
the part to operate with a wide range of power-supply
voltage inputs: 5V to 28V with protection up to 45V. The
Automotive, Two-Channel Proximity and
SENSED OBJECT
GROUND
ELECTRIC
FIELD
SIGNAL
regulator provides power for all the circuits making the
device a very compact single-chip solution.
The device's analog front-end is controlled by a number
of control registers. The C2D conversion results and
the AFE status are accessible through status and result
registers. All AFE registers are available in the micro-
controller data space. The control registers support read
and write operations. The status and result registers are
read-only registers.
Communication between the CPU and the external inter-
face and AFE registers is performed using read/write
operations to CPU special-function registers (SFRs).
The SFRs are organized in three sections (Section
I–Section III); each section consists of six modules
(M0–M5). Table 1 shows the location of each SFR within
the SFR sections (see the Detailed Description for more
details).
The sensed capacitance range can be set independent-
ly for both channels. After power-up, the range is set to
20pF in both channels.
CURRENT FLOW INTO
EXCITATION: SINUSOIDAL
CAPACITANCE I
MAX1441
VOLTAGE SOURCE
C
Sensed Capacitance Range
Touch Sensor
Control Registers
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