BU21170MUV

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TSZ02201-0L5L0F300830-1-2

© 2013 ROHM Co., Ltd. All rights reserved.

14.Jul.2016 Rev.002

www.rohm.com

TSZ22111・15・001

Block Diagram

LDO15

LDO28

VREF

OSC

Sensor

AFE

C/V

Converter

A/D

AVDD

DVDD

SIN0-4

LED0-4

LOGIC

AFE

MPU

WRAM

PROM

LEDDRV

VDD

VSS

SDA

SCL

TEST

AFE_CNT

PWM_CNT

INT

DTG

WDTR

POR

HOST

I/F

ADR

Block Descriptions

Sensor AFE , C/V Converter

Convert from capacitance to voltage following the order of sensors.

A/D

Convert from voltage to the detected result the digital value.

LDO28

2.73V output LDO for Sensor AFE, C/V Converter and A/D.

LDO15

1.5V output LDO for OSC and digital blocks.

OSC

Ring oscillator as the system clock.

POR

Power-On-Reset monitoring VDD as the system reset.

MPU

Based on the detection result, detect switch operations (Touch/Release/Hold) and run Auto-calibration.

Inform by the INT port to the host about that the switch operations are detected.

LED ports are controlled by the commands from the host.

HOST I/F

2-wire serial bus interface compatible with I

AFE_CNT

Sequencer of Sensor AFE, C/V converter and A/D.

PWM_CNT

PWM timers for the LED ports.

LEDDRV

LED port drivers.

WDTR

Watchdog timer Timeout Reset. It releases the system reset after 0.6sec from that MPU cannot clear WDTR.

(If MPU cannot clear WDTR, MPU is hung up.)

PROM

Program ROM for the included MPU.

WRAM

Work RAM for the included MPU.

Figure 6. Block Diagram