Rainbow Electronics MAX11835 User Manual

Preliminary, C interface

PRELIMINARY

_______________________________________________________________ Maxim Integrated Products 1

For pricing, delivery, and ordering information, please contact Maxim Direct at 1-888-629-4642,

or visit Maxim’s website at www.maxim-ic.com.

MAX11835

Haptic Piezo Controller with I

C Interface

19-xxxx; Rev 0; 1/10

General Description

The MAX11835 haptic (tactile) piezo controller provides
a complete solution to drive ceramic piezo actuators
to create haptic feedback for products featuring user
touch interfaces. The MAX11835 can drive single-layer
or multilayer piezo actuators over a wide range of volt-
ages up to 250V. It efficiently generates any type of user-
programmable waveforms including sine, trapezoidal,
square, and pulse to drive the piezo loads to create cus-
tom haptic sensations. The low-power MAX11835 direct-
ly interfaces with an application processor/host controller
through a standard serial interface and integrates vari-
ous blocks including a boost regulator, pattern storage
memory, and waveform generator block in one package,
thus providing a complete piezo driver solution.
The MAX11835 contains a boost regulator that uses
an external flyback to efficiently generate high-voltage
waveforms up to 250V to drive piezo actuators while lim-
iting current drain. The boost regulator features an inter-
nal n-channel MOSFET to set current limit and control the
drain from the battery or power supply.
The MAX11835 features user-programmable touch feed-
back pattern storage memory that drives the waveform
generator with piecewise linear data using 8-bit resolu-
tion. The device also offers a trigger feature that makes
it possible to use multiple haptic piezo controllers in
parallel to provide haptic sensations for larger displays.
Its smart, low-power, and standby modes reduce power
consumption before, during, and after waveform genera-
tion. The MAX11835 goes into low-power mode after a
haptic event to save power automatically.
The MAX11835 offers a fast 400kHz, I

C serial interface

to allow programming of various modes of operation,
status checking, and haptic waveforms. The operating
supply range includes 1.7V to 3.6V for digital supply and
2.7V to 5.25V for V

BATT

and A

VDD

Applications

Features

• Drives Single-Layer Piezo or Multilayer Actuators

with Waveform Peak Voltages up to 250V

• Creates Custom, User-Programmable Waveforms

with Up to 8-Bit Resolution

• Automatic Haptics Creation Without the Need for

Application Processor Intervention

• Audio Input Mode
• On-Chip, DC Boost Regulator

On-Chip, 33V, High-Voltage Boost Switch with

Programmable Maximum Peak Current

Flyback Converter Generates Piezo High-

Voltage Supply

Undervoltage Lockout Feature
Efficient Design to Minimize Drain on Battery

Applications

• On-Chip Multiple Haptic Waveform Storage Up to

192 Bytes

• TRIGb to Optionally Start a Preprogrammed

Waveform

• DISb to Disable or Enter Lower Power Boost

Operation During PA Burst

• 1.7V to 3.6V Digital Supply
• Boost/Flyback and 2.7V to 5.25V Analog Power

Supply (V

BATT

)

• Programmable Low-Power Modes

1µA Deep Sleep Shutdown Current

• Thermal Shutdown
• Available in 400kHz I

C Interface

ESD Protection: ±1kV HBM, ±1kV CDM, ±200V MM

Lead(Pb)-Free/RoHS-Compliant Package (0.4mm
Pitch)

Mobile Communication
Devices
PDA, GPS
Media Players,
Handheld Games

Portable Instruments
Resistive Touch-Enabled
Equipment
Capacitive Touch-Enabled
Equipment

Ordering Information

PART

TEMP RANGE

PIN-PACKAGE

MAX11835EWA+

-40NC to +85NC

25 WLP

Table of contents

Document Outline

Absolute Maximum Ratings
Electrical Characteristics
Timing Characteristics
Miscellaneous Timing Characteristics
Typical Operating Characteristics
Functional Diagram
Pin Configuration
Pin Description
Detailed Description
- FSR Calibration
- Force-Sense Resistor Signal Conditioning Interface
  - Purpose
  - Force-Sensor Characteristics
  - FSR Interface Architecture
  - Gain and Offset Range
- Reference Generator
- ADC
- Flyback Boost Controller
- Discharge Control Operational Amplifier
- Control Scheme
- Capacitor Fault Protection
- UVLO (Undervoltage Lockout)
Applications Information
- FSR Calibration
- Transformer Design
  - Minimum Transformer Turns Ratio
  - Primary Inductance
  - Leakage Inductance
  - Transformer Secondary Capacitance
  - Rectifying Diode
- Detailed Pin and Operational Description
  - GSMBL
  - RESET
  - WAKEUP
  - SDA
  - SCL
  - ADD5
  - IRQ
  - VLL, VUL, VLR, and VUR
  - DGND, AGND
  - VDD
  - VDDIO
  - VBAT
  - PGND, PGND2
  - SW, SW2
  - SEC
  - VFB
  - VDRIVE, VRTN
- Digital Interface
  - User-Accessible Address Locations
  - Hardware Configuration Register 1 (R/W): HCFG1 (0x20)
  - Hardware Configuration Register 2 (R/W): HCFG2 (0x21)
  - Scan Interval Counter Register (R/W): INTRV (0x01)
  - Press Threshold Register (R/W): PRTH (0x22)
  - VLR Calibration Register (R/W): CAL0 (0x23)
  - VLL Calibration Register (R/W): CAL1 (0x24)
  - VUR Calibration Register (R/W): CAL2 (0x25)
  - VUL Calibration Register (R/W): CAL3 (0x26)
  - Waveform Start Address Register (R/W): WVST (0x27)
  - Waveform Repetitions Register (R/W): WVREP (0x28)
  - Waveform Scaling Register (R/W): WVSCA (0x29)
  - ADC Scan Register (R/W): ADCSC (0x2A)
  - Software Reset Register (W): SRST (0x02)
  - Waveform Memory Address Pointer Register (W): WADDH (0x04) and WADDL (0x03)
  - Waveform Memory Data Register (R/W): WVDAT (0x05)
  - Flags/Status Register (R): FLAG (0x06)
  - Interrupt Mask Register (R/W): IMR (0x07)
  - FIFO Read Address Register (R): FIFOH (0x09) and FIFOL (0x08)
  - ID (Version Code) Register (R/W): IDREG (0x3F)
- Waveform SRAM Organization
- I2C-Compatible 2-Wire Interface
  - START (S) and STOP (P) Conditions
  - Early STOP Conditions
  - Slave Address
  - Acknowledge
  - Default Reads in I2C Mode
  - Example I2C Bus Cycles
- FIFO Detailed Operation
- MAX11836 Power States
  - DEEP_SLEEP
  - CHK_NXT
  - SCAN
  - DORMANT
  - WAKE
  - WAVE
  - SLEEP
Chip Information
Package Information