Burr-Brown Products ADS7846 from Texas Instruments SBAS125H-SEPTEMBER 1999-REVISED JANUARY 2005 TOUCH SCREEN CONTROLLER FEATURES DESCRIPTION SAME PINOUT AS ADS7843 The ADS7846 is a next-generation version to the industry 2.2V TO 5.25V OPERATION standard ADS7843 4-wire touch screen controller.The INTERNAL 2.5V REFERENCE ADS7846 is 100%pin-compatible with the existing ADS7843, and drops into the same socket.This allows for easy upgrade DIRECT BATTERY MEASUREMENT (OV to 6V) of current applications to the new version.Only software ON-CHIP TEMPERATURE MEASUREMENT changes are required to take advantage of the added fea- TOUCH-PRESSURE MEASUREMENT tures of direct battery measurement,temperature measure- QSPITM/SPITM 3-WIRE INTERFACE ment,and touch-pressure measurement.The ADS7846 also has an on-chip 2.5V reference that can be used for the ●AUTO POWER-DOWN auxiliary input,battery monitor,and temperature measure- TSSOP-16,SSOP-16,QFN-16, ment modes.The reference can also be powered down when AND VFBGA-48 PACKAGES not used to conserve power.The internal reference operates down to 2.7V supply voltage while monitoring the battery APPLICATIONS voltage from OV to 6V. PERSONAL DIGITAL ASSISTANTS The low-power consumption of 0.75mW (typ at 2.7V, reference off),high speed(up to 125kHz clock rate),and on- PORTABLE INSTRUMENTS chip drivers make the ADS7846 an ideal choice for battery- POINT-OF-SALE TERMINALS operated systems such as personal digital assistants(PDAs) ●PAGERS with resistive touch screens,pagers,cellular phones,and TOUCH SCREEN MONITORS other portable equipment.The ADS7846 is available in the small TSSOP-16,SSOP-16,QFN-16,and VFBGA-48 pack- ●CELLULAR PHONES ages and is specified over the-40C to +85C temperature US Patent No.6246394 range. QSPI and SPI are registered trademarks of Motorola. PENIRO SAR ADS784 -O DOUT -O BUSY 0 +O DCLK Please be aware that an important notice concerning availability,standard warranty,and use in critical applications of Texas Instruments semiconductor products and disclaimers thereto appears at the end of this data sheet. All trademarks are the property of their respective owners. Copyright 1999-2005,Texas Instruments Incorporated testing of all parameters. TEXAS INSTRUMENTS www.ti.com
FEATURES ● SAME PINOUT AS ADS7843 ● 2.2V TO 5.25V OPERATION ● INTERNAL 2.5V REFERENCE ● DIRECT BATTERY MEASUREMENT (0V to 6V) ● ON-CHIP TEMPERATURE MEASUREMENT ● TOUCH-PRESSURE MEASUREMENT ● QSPITM/SPITM 3-WIRE INTERFACE ● AUTO POWER-DOWN ● TSSOP-16, SSOP-16, QFN-16, AND VFBGA-48 PACKAGES APPLICATIONS ● PERSONAL DIGITAL ASSISTANTS ● PORTABLE INSTRUMENTS ● POINT-OF-SALE TERMINALS ● PAGERS ● TOUCH SCREEN MONITORS ● CELLULAR PHONES TOUCH SCREEN CONTROLLER DESCRIPTION The ADS7846 is a next-generation version to the industry standard ADS7843 4-wire touch screen controller. The ADS7846 is 100% pin-compatible with the existing ADS7843, and drops into the same socket. This allows for easy upgrade of current applications to the new version. Only software changes are required to take advantage of the added features of direct battery measurement, temperature measurement, and touch-pressure measurement. The ADS7846 also has an on-chip 2.5V reference that can be used for the auxiliary input, battery monitor, and temperature measurement modes. The reference can also be powered down when not used to conserve power. The internal reference operates down to 2.7V supply voltage while monitoring the battery voltage from 0V to 6V. The low-power consumption of < 0.75mW (typ at 2.7V, reference off), high speed (up to 125kHz clock rate), and onchip drivers make the ADS7846 an ideal choice for batteryoperated systems such as personal digital assistants (PDAs) with resistive touch screens, pagers, cellular phones, and other portable equipment. The ADS7846 is available in the small TSSOP-16, SSOP-16, QFN-16, and VFBGA-48 packages and is specified over the –40°C to +85°C temperature range. CDAC Internal 2.5V Reference SAR ADS7846 Comparator 6-Channel MUX Serial Data Out Temperature Sensor Battery Monitor DOUT BUSY CS DCLK DIN VBAT AUX VREF +VCC X+ X– Y+ Y– PENIRQ ADS7846 SBAS125H – SEPTEMBER 1999 – REVISED JANUARY 2005 www.ti.com PRODUCTION DATA information is current as of publication date. Products conform to specifications per the terms of Texas Instruments standard warranty. Production processing does not necessarily include testing of all parameters. Copyright © 1999-2005, Texas Instruments Incorporated US Patent No. 6246394 QSPI and SPI are registered trademarks of Motorola. AD ® S7846 ADS7846 ADS7846 Please be aware that an important notice concerning availability, standard warranty, and use in critical applications of Texas Instruments semiconductor products and disclaimers thereto appears at the end of this data sheet. All trademarks are the property of their respective owners
ABSOLUTE MAXIMUM RATINGS) ELECTROSTATIC +Vcc to GND -0.3Vto+6V Analog Inputs to GND -0.3V to +Vcc +0.3V DISCHARGE SENSITIVITY Digital Inputs to GND. -0.3V to +Vcc +0.3V Power Dissipation.250mw This integrated circuit can be damaged by ESD.Texas Instru- Maximum Junction Temperature +150°℃ ments recommends that all integrated circuits be handled with Operating Temperature Range .40°℃t0+85℃ appropriate precautions.Failure to observe proper handling Storage Temperature Range 65℃to+150℃ and installation procedures can cause damage. Lead Temperature (soldering,10s)..... .+300℃ NOTE:(1)Stresses above these ratings can cause permanent damage. ESD damage can range from subtle performance degradation Exposure to absolute maximum conditions for extended periods may degrade to complete device failure.Precision integrated circuits may be device reliability. more susceptible to damage because very small parametric changes could cause the device not to meet its published specifications. PACKAGE/ORDERING INFORMATION) MAXIMUM INTEGRAL SPECIFIED LINEARITY PACKAGE TEMPERATURE PACKAGE ORDERING PRODUCT ERROR (LSB) PACKAGE-LEAD DESIGNATOR RANGE MARKING NUMBER ADS7846E 轻 SSOP-16 DBQ 40°℃to+85℃ ADS7846E ADS7846E ADS7846E/2K5 ADS7846N 轻 TSSOP-16 PW -40°℃to+85℃ ADS7846N ADS7846N ADS7846N/2K5 ADS7846N/2K5G4 ADS78461 2 VFBGA-48 GQC 40°℃to+85C ADS7846 ADS7846IGQCR ADS7846I 积 QFN-16 RGV 40℃t0+85℃ ADS7846 ADS7846IRGVT ADS7846IRGVR NOTE:(1)For the most current package and ordering information,see the Package Option Addendum located at the end of this data sheet,or see the TI web site at www.ti.com. TEXAS 2 INSTRUMENTS ADS7846 www.ti.com SBAS125H
ADS7846 2 www.ti.com SBAS125H ABSOLUTE MAXIMUM RATINGS(1) +VCC to GND ........................................................................ –0.3V to +6V Analog Inputs to GND ............................................ –0.3V to +VCC + 0.3V Digital Inputs to GND ............................................. –0.3V to +VCC + 0.3V Power Dissipation .......................................................................... 250mW Maximum Junction Temperature ................................................... +150°C Operating Temperature Range ........................................ –40°C to +85°C Storage Temperature Range ......................................... –65°C to +150°C Lead Temperature (soldering, 10s) ............................................... +300°C NOTE: (1) Stresses above these ratings can cause permanent damage. Exposure to absolute maximum conditions for extended periods may degrade device reliability. MAXIMUM INTEGRAL SPECIFIED LINEARITY PACKAGE TEMPERATURE PACKAGE ORDERING PRODUCT ERROR (LSB) PACKAGE-LEAD DESIGNATOR RANGE MARKING NUMBER ADS7846E ±2 SSOP-16 DBQ –40°C to +85°C ADS7846E ADS7846E "" " " " " ADS7846E/2K5 ADS7846N ±2 TSSOP-16 PW –40°C to +85°C ADS7846N ADS7846N "" " " " " ADS7846N/2K5 "" " " " " ADS7846N/2K5G4 ADS7846I ±2 VFBGA-48 GQC –40°C to +85°C ADS7846 ADS7846IGQCR ADS7846I ±2 QFN-16 RGV –40°C to +85°C ADS7846 ADS7846IRGVT "" " " " " ADS7846IRGVR NOTE: (1) For the most current package and ordering information, see the Package Option Addendum located at the end of this data sheet, or see the TI web site at www.ti.com. PACKAGE/ORDERING INFORMATION(1) ELECTROSTATIC DISCHARGE SENSITIVITY This integrated circuit can be damaged by ESD. Texas Instruments recommends that all integrated circuits be handled with appropriate precautions. Failure to observe proper handling and installation procedures can cause damage. ESD damage can range from subtle performance degradation to complete device failure. Precision integrated circuits may be more susceptible to damage because very small parametric changes could cause the device not to meet its published specifications
ELECTRICAL CHARACTERISTICS At TA=-40C to +85C.+Vcc=+2.7V,VREF=2.5V internal voltage.fsAMPLE=125kHz,foLk=16.fsAMPLE=2MHz,12-bit mode,and digital inputs =GND or +Vcc. unless otherwise noted. ADS7846E PARAMETER CONDITIONS MIN TYP MAX UNITS ANALOG INPUT Full-Scale Input Span Positive Input-Negative Input 0 VREF Absolute Input Range Positive Input Negative Input +Vcc+0.2 +0.2 Capacitance Leakage Current 9 A SYSTEM PERFORMANCE Resolution Bits No Missing Codes 方 12 Bits Integral Linearity Error 2 LSB(1) Offset Error LSB Gain Error Extemal VREF LSB Noise Including Internal VREF 70 uVrms Power-Supply Rejection 70 dB SAMPLING DYNAMICS Conversion Time 12 CLK Cycles Acquisition Time 3 CLK Cycles Throughput Rate 125 kHz Multiplexer Settling Time 500 ns Aperture Delay Aperture Jitter Channel-to-Channel Isolation ViN 2.5Vp-p at 50kHz 100 B SWITCH DRIVERS On-Resistance Y+,X+ 6 Q Y-,X- Drive Current(2) Duration 100ms 50 mA REFERENCE OUTPUT Internal Reference Voltage 2.45 2.50 2.55 Internal Reference Drift 15 ppmC Quiescent Current 500 A REFERENCE INPUT Range 1.0 +Vcc Input Impedance SER/DFR =0.PD1=0. 1 GO Internal Reference Off Internal Reference On 250 0 BATTERY MONITOR Input Voltage Range 0.5 6.0 Input Impedance Sampling Battery kO Battery Monitor Off 1 Accuracy External VREF 2.5V -2 +2 % Intemal Reference -3 +3 TEMPERATURE MEASUREMENT Temperature Range -40 +85 C Resolution Differential Method(3) 1.6 TEMPO(4) . Accuracy Differential Method(3) 2 TEMP0(4) C DIGITAL INPUT/OUTPUT Logic Family CMOS Logic Levels,Except PENIRQ Vi |IH|≤+5uA +Vcc·0.7 +Vcc+0.3 1l|≤+5uA 0.3 +0.8 VoH 1oH=-250uA +Wcc·0.8 > o IoL =250uA 0.4 Dg的Fomat TA=0Cto+85℃，50k2Pu-Up 0.8 Straight Binary POWER-SUPPLY REQUIREMENTS +Vcc(5) Specified Performance 2.7 3.6 Operating Range 2.2 5.25 v Quiescent Current Internal Reference Off 280 650 Intemnal Reference On 780 fsAMPLE 12.5kHz 220 A Power-Down Mode with 3 CS=DCLK=DIN =+Vcc Power Dissipation +Vcc=+2.7V 1.8 mW TEMPERATURE RANGE Specified Performance -40 +85 ℃ NOTES:(1)LSB means least significant bit.With VREF equal to +2.5V.one LSB is 610uV.(2)Ensured by design,but not tested.Exceeding 50mA source current may result in device degradation.(3)Difference between TEMPO and TEMP1 measurement.No calibration necessary.(4)Temperature drift is -2.1mV/C. (5)ADS7846 operates down to 2.2V. ADS7846 TEXAS INSTRUMENTS 3 SBAS125H www.ti.com
ADS7846 3 SBAS125H www.ti.com ANALOG INPUT Full-Scale Input Span Positive Input-Negative Input 0 VREF V Absolute Input Range Positive Input –0.2 +VCC + 0.2 V Negative Input –0.2 +0.2 V Capacitance 25 pF Leakage Current 0.1 µA SYSTEM PERFORMANCE Resolution 12 Bits No Missing Codes 11 Bits Integral Linearity Error ±2 LSB(1) Offset Error ±6 LSB Gain Error External VREF ±4 LSB Noise Including Internal VREF 70 µVrms Power-Supply Rejection 70 dB SAMPLING DYNAMICS Conversion Time 12 CLK Cycles Acquisition Time 3 CLK Cycles Throughput Rate 125 kHz Multiplexer Settling Time 500 ns Aperture Delay 30 ns Aperture Jitter 100 ps Channel-to-Channel Isolation VIN = 2.5Vp-p at 50kHz 100 dB SWITCH DRIVERS On-Resistance Y+, X+ 5 Ω Y–, X– 6 Ω Drive Current(2) Duration 100ms 50 mA REFERENCE OUTPUT Internal Reference Voltage 2.45 2.50 2.55 V Internal Reference Drift 15 ppm/°C Quiescent Current 500 µA REFERENCE INPUT Range 1.0 +VCC V Input Impedance SER/DFR = 0, PD1 = 0, 1 GΩ Internal Reference Off Internal Reference On 250 Ω BATTERY MONITOR Input Voltage Range 0.5 6.0 V Input Impedance Sampling Battery 10 kΩ Battery Monitor Off 1 GΩ Accuracy External VREF = 2.5V –2 +2 % Internal Reference –3 +3 % TEMPERATURE MEASUREMENT Temperature Range –40 +85 °C Resolution Differential Method(3) 1.6 °C TEMP0(4) 0.3 °C Accuracy Differential Method(3) ±2 °C TEMP0(4) ±3 °C DIGITAL INPUT/OUTPUT Logic Family CMOS Logic Levels, Except PENIRQ VIH | IIH | ≤ +5µA +VCC • 0.7 +VCC + 0.3 VIL | IIL | ≤ +5µA –0.3 +0.8 V VOH IOH = –250µA +VCC • 0.8 V VOL IOL = 250µA 0.4 V PENIRQ VOL TA = 0°C to +85°C, 50kΩ Pull-Up 0.8 V Data Format Straight Binary POWER-SUPPLY REQUIREMENTS +VCC(5) Specified Performance 2.7 3.6 V Operating Range 2.2 5.25 V Quiescent Current Internal Reference Off 280 650 µA Internal Reference On 780 µA fSAMPLE = 12.5kHz 220 µA Power-Down Mode with 3 µA CS = DCLK = DIN = +VCC Power Dissipation +VCC = +2.7V 1.8 mW TEMPERATURE RANGE Specified Performance –40 +85 °C NOTES: (1) LSB means least significant bit. With VREF equal to +2.5V, one LSB is 610µV. (2) Ensured by design, but not tested. Exceeding 50mA source current may result in device degradation. (3) Difference between TEMP0 and TEMP1 measurement. No calibration necessary. (4) Temperature drift is –2.1mV/°C. (5) ADS7846 operates down to 2.2V. ADS7846E PARAMETER CONDITIONS MIN TYP MAX UNITS ELECTRICAL CHARACTERISTICS At TA = –40°C to +85°C, +VCC = +2.7V, VREF = 2.5V internal voltage, fSAMPLE = 125kHz, fCLK = 16 • fSAMPLE = 2MHz, 12-bit mode, and digital inputs = GND or +VCC, unless otherwise noted
PIN CONFIGURATION Top View SSOP,TSSOP Top View VFBGA DCLK DIN BUSY DOUT +Vcc 1 DCLK 2 3 5 X+ 2 cS A NC O 四 Y+ 34 DIN B○ © © © © © Q 太 BUSY +cc PENIRO Y- 5 ADS7846 43211 DOUT cO © 四 © © Q +Vcc GND 6 PENIRQ O © * © 四 © 四 Q VREF Vaur +Vcc 8 E○ 四 四 © © © Q AUX VREF AUX F© © © 四四 © X- Y-GND GND Top View QFN 5o0 odIN3d 9皇 9 BUSY 2 AUX DIN VaAT 23 ADS7846 10 GND DCLK Y- ooN PIN DESCRIPTION SSOP AND TSSOP PIN# VFBGA PIN QFN PIN NAME DESCRIPTION 1 B1 and C1 5 +Vcc Power Supply D1 X+ X+Position Input 3 7890 Y+ Y+Position Input 456 2 X-Position Input Y-Position Input G4 and G5 GND Ground G6 VBAT Battery Monitor Input 8910 ha 6 12 AUX Auxiliary Input to ADC er Voltage Reference Input/Output +Vo Digital 1/O Power Supply 1 B7 15 PENIRQ Pen Interrupt Open anode output (requires 10kn to 100k pull-up resistor extemally). DOUT Serial Data Output.Data is shifted on the falling edge of DCLK.This output is high impedance when CS is high. 13 A5 话 船 123 Busy Output.This output is high impedance when CS is high. 器 Serial Data Input.If CS is low,data is latched on rising edge of DCLK. pdontaeoCcW0nmntesesanpt6oiea 16 A2 4 DCLK Extemal Clock Input.This clock runs the SAR conversion process and synchronizes serial data VO. TEXAS 4 INSTRUMENTS ADS7846 www.ti.com SBAS125H
ADS7846 4 www.ti.com SBAS125H PIN CONFIGURATION Top View SSOP, TSSOP Top View VFBGA 1 2 3 4 5 6 7 8 +VCC X+ Y+ X– Y– GND VBAT AUX DCLK CS DIN BUSY DOUT PENIRQ +VCC VREF 16 15 14 13 12 11 10 9 ADS7846 NC A NC 1 2 3 4 5 6 7 DCLK +VCC +VCC X+ Y+ PENIRQ +VCC VREF AUX CS DIN BUSY DOUT X– Y– GND GND VBAT NC NC NC NC NC B C D E F NC NC NC NC NC NC NC NC NC NC NC NC NC NC NC NC NC NC NC NC NC NC G NC BUSY DIN CS DCLK AUX VBAT GND Y– 1 2 3 4 12 11 10 9 ADS7846 DOUT PENIRQ +VCC VREF 16 15 14 13 +VCC X+ Y+ X– 5 6 7 8 Top View QFN SSOP AND TSSOP PIN # VFBGA PIN # QFN PIN # NAME DESCRIPTION 1 B1 and C1 5 +VCC Power Supply 2 D1 6 X+ X+ Position Input 3 E1 7 Y+ Y+ Position Input 4 G2 8 X– X– Position Input 5 G3 9 Y– Y– Position Input 6 G4 and G5 10 GND Ground 7 G6 11 VBAT Battery Monitor Input 8 E7 12 AUX Auxiliary Input to ADC 9 D7 13 VREF Voltage Reference Input/Output 10 C7 14 +VCC Digital I/O Power Supply 11 B7 15 PENIRQ Pen Interrupt. Open anode output (requires 10kΩ to 100kΩ pull-up resistor externally). 12 A6 16 DOUT Serial Data Output. Data is shifted on the falling edge of DCLK. This output is high impedance when CS is high. 13 A5 1 BUSY Busy Output. This output is high impedance when CS is high. 14 A4 2 DIN Serial Data Input. If CS is low, data is latched on rising edge of DCLK. 15 A3 3 CS Chip Select Input. Controls conversion timing and enables the serial input/output register. CS high = power-down mode (ADC only). 16 A2 4 DCLK External Clock Input. This clock runs the SAR conversion process and synchronizes serial data I/O. PIN DESCRIPTION
TYPICAL CHARACTERISTICS At TA=+25C.+Vcc =+2.7V,VREF External +2.5V,fsAMPLE=125kHz,and foLk=16.fsAMPLE 2MHz,unless otherwise noted. POWER-DOWN SUPPLY CURRENT SUPPLY CURRENT vs TEMPERATURE vs TEMPERATURE 400 140 350 120 300 100 2 80 20 60 150 40 100 20 40 -20 0 20 40 60 80 100 40 -20 0 20 40 60 80 100 Temperature (C) Temperature (C) SUPPLY CURRENT vS +Vcc MAXIMUM SAMPLE RATE vs +Vcc 390 1M 370 50 fSAMPLE =12.5kHz 100K 30 3 10k 290 270 250 依 2.0 2.5 3.0 3.5 4.0 4.5 5.0 2.0 2.5 3.0 3.5 4.0 4.5 5.0 +Vcc (V) +Vcc (V) CHANGE IN GAIN Vs TEMPERATURE CHANGE IN OFFSET Vs TEMPERATURE 0.15 0.6 0.10 0.4 (as7) 0.05 0.2 0 0 -0.05 0.2 0.10 0.4 0.15 0.6 40 -20 0 2040 60 80 100 40 -20 0 204060 80 100 Temperature (C) Temperature(C) ADS7846 TEXAS INSTRUMENTS SBAS125H www.ti.com
ADS7846 5 SBAS125H www.ti.com TYPICAL CHARACTERISTICS At TA = +25°C, +VCC = +2.7V, VREF = External +2.5V, fSAMPLE = 125kHz, and fCLK = 16 • fSAMPLE = 2MHz, unless otherwise noted. SUPPLY CURRENT vs TEMPERATURE –40 100 –20 0 40 20 Temperature (°C) Supply Current (µA) 400 350 300 250 200 150 100 60 80 POWER-DOWN SUPPLY CURRENT vs TEMPERATURE –40 100 –20 0 40 20 Temperature (°C) Supply Current (nA) 140 120 100 80 60 40 20 60 80 SUPPLY CURRENT vs +VCC 2.0 5.0 2.5 4.0 3.5 +VCC (V) Supply Current (µA) 390 370 350 330 310 290 270 250 3.0 4.5 f SAMPLE = 12.5kHz MAXIMUM SAMPLE RATE vs +VCC 2.0 5.0 2.5 4.0 3.5 +VCC (V) Sample Rate (Hz) 1M 100k 10k 1k 3.0 4.5 CHANGE IN GAIN vs TEMPERATURE –40 100 –20 0 40 20 Temperature (°C) Delta from +25°C (LSB) 0.15 0.10 0.05 0 –0.05 –0.10 –0.15 60 80 CHANGE IN OFFSET vs TEMPERATURE –40 100 –20 0 40 20 Temperature (°C) Delta from +25°C (LSB) 0.6 0.4 0.2 0 –0.2 –0.4 –0.6 60 80