AK4186EN

Overview

The AK4186EN is a low-power touch screen controller manufactured by Asahi Kasei Microdevices (AKM). It supports both 4-wire and 5-wire resistive touch screens and integrates a 12-bit SAR A/D converter with a sample-and-hold circuit. The device operates on a supply voltage of 1.6V to 3.6V, consuming 60µA at 1.8V in normal mode. It features an I2C serial interface supporting standard (100kHz) and fast (400kHz) modes, along with an integrated internal oscillator for sequence mode operation. The component includes a median averaging filter and automatic continuous measurement capabilities to reduce microprocessor overhead.

Feature Summary

• Supports 4-wire and 5-wire resistive touch screen interfaces with pen pressure measurement capability for 4-wire configurations.
• Integrates a 12-bit SAR A/D converter with a throughput rate of 22.2kHz and an internal median averaging filter.
• Features an I2C serial interface compatible with standard and fast modes, utilizing a CMOS PENIRQN buffer output for interrupt signaling.
• Operates from a single supply voltage ranging from 1.6V to 3.6V with low power consumption of 60µA at 1.8V.

Applications

• Cellular phones
• Digital Still Cameras (DSC)
• Digital Video Cameras (DVC)
• Smartphones
• Portable devices requiring low-voltage microprocessor connectivity

Procurement Notes

Verify the specific ordering suffix EN corresponds to the 16-pin QFN package (3mm x 3mm, 0.5mm pitch) as defined in the manufacturer's ordering guide. Confirm that the CAD0 pin configuration matches the intended I2C slave address requirements for the target system design.

Selection Notes

Select the AK4186EN when a 16-pin QFN footprint is required instead of the 12-pin CSP variant. Ensure the application utilizes 4-wire or 5-wire resistive touch panels, as the device does not support capacitive interfaces. Verify that the host microprocessor supports I2C communication at speeds up to 400kHz and operates within the 1.6V to 3.6V supply range.

Part Context

The AK4186EN is part of the AK4186 series of low-power touch screen controllers. It shares core functional specifications with the AK4186ECB but differs in physical packaging. The EN suffix specifically denotes the 16-pin QFN package, while the ECB suffix denotes the 12-pin CSP package. Both variants offer identical electrical performance and feature sets.

Replacement Considerations

Publicly confirmed substitute part numbers are not available in the provided documentation. Designers should consult the manufacturer for current alternative components if the AK4186EN is unavailable.

FAQ

Does the AK4186EN support High Speed Mode I2C-bus systems?

No, the AK4186EN supports only standard mode (100kHz) and fast mode (400kHz) I2C bus operations. It does not support High Speed Mode I2C-bus systems (3.4MHz).

How is pen pressure measured on this device?

Pen pressure measurement is supported only for 4-wire touch screens. The device calculates contact resistance using results from X-position, Z1-position, and Z2-position conversions.

What is the function of the NC pins on the AK4186EN?

Pins 5, 8, 13, and 16 are No Connection (NC) pins with no internal bonding. They must be connected to VSS (Ground) during PCB assembly.

Can the AK4186EN measure auxiliary analog inputs?

Yes, the device includes an Auxiliary Analog Input (IN/WIPER pin). In 4-wire mode, it functions as IN; in 5-wire mode, it functions as WIPER for top touch panel input.