AD7147ACPZ-REEL

Overview

The AD7147ACPZ-REEL is a CapTouch programmable controller for single-electrode capacitance sensors, manufactured by Analog Devices Inc. It integrates a 16-bit, 250 kHz sigma-delta capacitance-to-digital converter (CDC) with 13 sensor inputs. The device operates on a 2.6 V to 3.6 V supply and features an SPI-compatible serial interface. Key specifications include a 9 ms update rate for all 13 inputs, femtofarad resolution, and on-chip automatic calibration logic for environmental compensation. It consumes 1 mA in full power mode and approximately 21.5 μA in low power mode.

Feature Summary

• Integrated 16-bit capacitance-to-digital converter with 13 sensor inputs
• SPI-compatible serial interface with separate VDRIVE level
• On-chip automatic calibration and adaptive threshold logic
• Low operating current: 1 mA (full power), 21.5 μA (low power)

Applications

• Cell phones
• Personal music and multimedia players
• Smart handheld devices
• Television, A/V, and remote controls
• Gaming consoles

Procurement Notes

Verify the REEL suffix indicates tape-and-reel packaging when sourcing. Confirm the specific lot date code and RoHS compliance status with the distributor or manufacturer prior to purchase. Ensure the ordering part number matches the exact package and interface requirements for the target design.

Selection Notes

Select the AD7147ACPZ-REEL for designs requiring an SPI interface; use the AD7147-1 variant if I2C compatibility is needed. Ensure the host processor supports the required SPI timing specifications. Verify that the application environment falls within the -40°C to +85°C operating temperature range for standard commercial grade parts.

Part Context

This component belongs to the AD7147 family of CapTouch controllers. It is functionally similar to the AD7142 but offers additional channels and enhanced calibration features. The 'ACPZ' designation refers to the 24-lead, 4 mm × 4 mm LFCSP package. The 'REEL' suffix specifies the bulk packaging format for high-volume manufacturing.

Replacement Considerations

The AD7147-1ACPZ-RL serves as a direct functional substitute if an I2C interface is acceptable instead of SPI. Other members of the AD714x family may require register map adjustments due to differences in channel count or feature sets.

FAQ

What is the maximum SCLK frequency for the SPI interface?

The maximum SCLK frequency is 5 MHz.

How does the AD7147 handle environmental changes?

It uses on-chip automatic calibration logic and adaptive threshold levels to compensate for environmental changes such as humidity and temperature variations.

What is the purpose of the ACSHIELD pin?

The ACSHIELD pin provides an active shield output at 250 kHz to minimize noise pickup in the external capacitance sensors.