SX8661Z datasheet(24/87 Pages) SEMTECH

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ADVANCED COMMUNICATIONS & SENSING

DATASHEET

Revision v4.0, February 2016

www.semtech.com

SX8661Z

Low Power, Capacitive Button Touch and Proximity Controller

(8 sensors) with LED Drivers and Analog Output

micro

processor

MTP

NVM

I2C

HOST

SPM

SX8661Z

Figure 20

Host NVM mode

The writing of the host towards the NVM is not done directly but done in 2 steps (Figure 20).

In the first step the host writes to the SPM (as in Figure 19). In the second step the host signals the SX8661Z to

copy the SPM content into the NVM.

Initially the NVM memory is empty and it is required to determine a valid parameter set for the application. This

can be done during the development phase using dedicated evaluation hardware representing the final

application. This development phase uses probably initially the host SPM mode which allows faster iterations.

Once the parameter set is determined this can be written to the NVM over the I2C using the 2 steps approach by

the host or a dedicated programmer for large volumes production (as described in the paragraphs 6.6 and 6.7).

3.12 Power Management

The SX8661Z uses on-chip voltage regulators which are controlled by the on-chip microprocessor. The regulators

need to be stabilized with an external capacitor between VANA and ground and between VDIG and ground (see

Table 5). Both regulators are designed to only drive the SX8661Z internal circuitry and must not be loaded

externally.

3.13 Clock Circuitry

The SX8661Z has its own internal clock generation circuitry that does not require any external components. The

clock circuitry is optimized for low power operation and is controlled by the on-chip microprocessor. The typical

operating frequency of the oscillating core is 16.7MHz from which all other lower frequencies are derived.

3.14 I2C interface

The I2C interface allows the communication between the host and the SX8661Z.

The I2C slave implemented on the SX8661Z is compliant with the standard (100kb/s) and fast mode (400kb/s)

The default SX8661Z I2C address equals 0b010 1011.

A different I2C address can be programmed by the user in the NVM.

SX8661Z Datasheet(PDF) 24 Page - Semtech Corporation