Circuit Note

CN-0274

Rev. A | Page 5 of 6

Figure 3. Photo of EVAL-CN0274-SDPZ PCB

COMMON VARIATIONS

The maximum continuous operating current of the ADP195 is

fixed at 1.1 A. For applications requiring more downstream power,

a higher current rated switch can be used in place of the ADP195.

By sacrificing approximately 15 µA of quiescent current, the

ADP197 is capable of providing 3 A of current to downstream

circuitry. For applications requiring less downstream power, the

ADP190 can be used. It has a continuous current of 500 mA

and is available in a smaller WLCSP package than the ADP195.

A second variant of the provided solution is to create a free fall

detection system. This function can be implemented using the

inactivity interrupt. When an object is in true free-fall, acceleration

on all axes is 0 g. Thus, free-fall detection is achieved by looking

for acceleration on all axes to fall below a certain threshold (close to

0 g) for a certain amount of time.

The ADXL362 functions as a free-fall detector by setting the

inactivity threshold (300 mg to 600 mg) and inactivity time

(150 ms to 350 ms). The register setting for these values varies

based on the g-range setting of the device.

CIRCUIT EVALUATION AND TEST

This circuit uses the EVAL-SDP-CS1Z System Demonstration

Platform (SDP) evaluation board and the EVAL-CN0274-SDPZ

circuit board. The two boards have 120-pin mating connectors,

allowing for the quick setup and evaluation of the performance

of the circuit.

The EVAL-CN0274-SDPZ contains the circuit to be evaluated,

as described in this note, and the EVAL-SDP-CS1Z is used with

the CN0274 evaluation software to capture the data from the

EVAL-CN0274-SDPZ.

Because the ADXL362 requires a relatively small amount of

power in both the asleep and awake states, it is possible to

power the EVAL-CN0274-SDPZ from the digital data lines

coming out of the EVAL-SDP-CS1Z.

Equipment Needed

The following equipment is needed:

• A PC with a USB port and Windows® XP or Windows Vista®

(32-bit), or Windows® 7 (32-bit)

• The EVAL-CN0274-SDPZ evaluation board

• The EVAL-SDP-CS1Z evaluation board

• The CN0274 Evaluation Software

• A power supply: 3.0 V or 2 AAA batteries.

Getting Started

Load the evaluation software by placing the CN0274 evaluation

software CD into the PC. Using My Computer, locate the drive

that contains the evaluation software CD and open the Readme

file. Follow the instructions contained in the Readme file for

installing and using the evaluation software.