19-3562; Rev 1; 6/05 10-Bit, Dual, Nonvolatile, Linear-Taper Digital Potentiometers ♦ 35ppm/°C End-to-End Resistance Temperature Coefficient ♦ 5ppm/°C Ratiometric Temperature Coefficient ♦ 10kΩ and 50kΩ End-to-End Resistor Values ♦ 3-Wire SPI-Compatible Serial Interface ♦ Reliability (TA = +85°C) 50,000 Wiper Store Cycles 50 Years Wiper Data Retention ♦ 1.5µA (max) Standby Current ♦ Single +2.7V to +5.25V Supply Operation ♦ Dual ±2.5V Supply Operation N.C. 14 N.C. 15 L1 H1 9 MAX5494 MAX5495 2 3 L2 8 VSS 7 N.C. 6 N.C. 5 VDD 8 VSS 7 N.C. 6 N.C. 5 VDD 4 H2 1 GND W1 L1 D.N.C. 12 11 10 9 N.C. 14 T1655-2 MAX5495ETE -40°C to +85°C 16 TQFN-EP* T1655-2 *EP = Exposed pad. Ordering Information continued at end of data sheet. Selector Guide appears at end of data sheet. SPI is a trademark of Motorola, Inc. 1 2 3 4 D.N.C. -40°C to +85°C 16 TQFN-EP* SCLK 16 L2 MAX5494ETE MAX5496 MAX5497 W2 PKG CODE INTERFACE DIN 13 CS TEMP RANGE 10 5mm × 5mm × 0.8mm TQFN N.C. 15 PART 11 SCLK 16 Ordering Information PINPACKAGE 12 DIN 13 Applications Gain and Offset Adjustment LCD Contrast Adjustment Pressure Sensors Low-Drift Programmable-Gain Amplifiers Mechanical Potentiometer Replacement Volume Control W1 TOP VIEW GND Pin Configurations W2 The MAX5494–MAX5499 operate with either a single power supply (+2.7V to +5.25V) or dual power supplies (±2.5V). The devices consume 400µA (max) of supply current when writing data to the nonvolatile memory and 1.5µA (max) of standby supply current. The devices are available in space-saving (5mm x 5mm x 0.8mm), 16-pin TQFN package and are specified over the extended (-40°C to +85°C) temperature range. ♦ 16-Pin, 5mm x 5mm x 0.8mm TQFN Package INTERFACE The MAX5494–MAX5499 are ideal for applications requiring digitally controlled potentiometers. End-to-end resistance values of 10kΩ and 50kΩ are available with a 35ppm/°C end-to-end temperature coefficient. The ratiometric temperature coefficient is 5ppm/°C for each channel, making these devices ideal for applications requiring low-temperature-coefficient programmable voltagedividers such as low-drift, programmable-gain amplifiers. ♦ Wiper Position Stored in Nonvolatile Memory and Recalled Upon Power-Up CS The MAX5494–MAX5499 10-bit (1024-tap), dual, nonvolatile, linear-taper, programmable voltage-dividers and variable resistors perform the function of a mechanical potentiometer, but replace the mechanics with a 3-wire SPI™-compatible serial interface. The MAX5494/MAX5495 are dual, 3-terminal, programmable voltage-dividers; the MAX5496/MAX5497 are dual, 2-terminal variable resistors; and the MAX5498/ MAX5499 include one 2-terminal variable resistor and one 3-terminal programmable voltage-divider. The MAX5494–MAX5499 feature an internal, nonvolatile, electrically erasable programmable read-only memory (EEPROM) that stores the wiper position for initialization during power-up. The 3-wire SPI-compatible serial interface allows communication at data rates up to 7MHz. Features 5mm × 5mm × 0.8mm TQFN Pin Configurations continued at end of data sheet. ________________________________________________________________ Maxim Integrated Products For pricing, delivery, and ordering information, please contact Maxim/Dallas Direct! at 1-888-629-4642, or visit Maxim’s website at www.maxim-ic.com. 1 MAX5494–MAX5499 General Description MAX5494–MAX5499 10-Bit, Dual, Nonvolatile, Linear-Taper Digital Potentiometers ABSOLUTE MAXIMUM RATINGS VDD to GND ...........................................................-0.3V to +6.0V VSS to GND............................................................-6.0V to +0.3V VDD to VSS .............................................................-0.3V to +6.0V H1, H2, L1, L2, W1, W2 to VSS.........(VSS - 0.3V) to (VDD + 0.3V) CS, SCLK, DIN to GND ..............................-0.3V to (VDD + 0.3V) Maximum Continuous Current into H_, L_, and W_ MAX5494/MAX5496/MAX5498 ....................................±5.0mA MAX5495/MAX5497/MAX5499 ....................................±1.0mA Maximum Current Into Other Pins .................................±50.0mA Continuous Power Dissipation (TA = +70°C) 16-Pin TQFN (derate 20.8mW/°C above +70°C) ....1666.7mW Operating Temperature Range ...........................-40°C to +85°C Junction Temperature ......................................................+150°C Storage Temperature Range .............................-60°C to +150°C Lead Temperature (soldering, 10s) .................................+300°C Stresses beyond those listed under “Absolute Maximum Ratings” may cause permanent damage to the device. These are stress ratings only, and functional operation of the device at these or any other conditions beyond those indicated in the operational sections of the specifications is not implied. Exposure to absolute maximum rating conditions for extended periods may affect device reliability. ELECTRICAL CHARACTERISTICS (VDD = +2.7V to +5.25V, VSS = GND = 0, VH_ = VDD, VL_ = 0, TA = -40°C to +85°C, unless otherwise noted. Typical values are at VDD = +5.0V, TA = +25°C.) (Note 1) PARAMETER SYMBOL CONDITIONS MIN TYP MAX UNITS DC PERFORMANCE (MAX5494/MAX5495/MAX5498/MAX5499 Programmable Voltage-Divider) Resolution N Integral Nonlinearity (Note 2) INL Differential Nonlinearity (Note 2) DNL End-to-End Resistance Temperature Coefficient TCR 10 ±2 VDD = 5V ±2 VDD = 2.7V ±1 VDD = 5V ±1 Ratiometric Temperature Coefficient Full-Scale Error FSE Zero-Scale Error ZSE Wiper Capacitance CW End-to-End Resistance RHL Channel-to-Channel Division Ratio Matching Bits VDD = 2.7V ppm/°C 5 ppm/°C MAX5494/MAX5498 -4 -2.5 0 -4 -0.75 0 MAX5494/MAX5498 0 3.3 5 MAX5495/MAX5499 0 1.45 5 60 7.5 10 12.5 MAX5495/MAX5499 37.5 50 62.5 MAX5494 0.05 MAX5495 0.15 LSB kΩ % 6.3 kΩ Resistance from W_ to L_ and H_ MAX5495/MAX5499, W_ at 15 code, H_ and L_ shorted to VSS, measure resistance from W_ to H_ (Figures 4 and 5) 2 LSB pF MAX5494/MAX5498 MAX5494/MAX5498, W_ at 15 code, H_ and L_ shorted to VSS, measure resistance from W_ to H_ (Figures 4 and 5) LSB 35 MAX5495/MAX5499 VDD = 3V, midcode: 512 LSB 25 _______________________________________________________________________________________ 10-Bit, Dual, Nonvolatile, Linear-Taper Digital Potentiometers (VDD = +2.7V to +5.25V, VSS = GND = 0, VH_ = VDD, VL_ = 0, TA = -40°C to +85°C, unless otherwise noted. Typical values are at VDD = +5.0V, TA = +25°C.) (Note 1) PARAMETER SYMBOL CONDITIONS MIN TYP MAX UNITS DC PERFORMANCE (MAX5496–MAX5499 Variable Resistor) Resolution N 10 VDD = 2.7V Integral Nonlinearity (Note 3) INL_R VDD = 3V -4 VDD = 5V -4 VDD = 2.7V Differential Nonlinearity (Note 3) Variable-Resistor Temperature Coefficient Wiper Resistance DNL_R TCVR RW Wiper Capacitance CWR Full-Scale Wiper-to-End Resistance RW-L Zero-Scale Resistor Error RZ Two-Channel Resistance Matching Bits -1.6 -1.4 +4 -1.3 +4 +0.45 VDD = 3V -1 +0.4 +1 VDD = 5V -1 +0.35 +1 VDD = 3V to 5.25V; code = 128 to 1024 35 VDD ≥ 3V (Note 4) 50 Ω 60 pF 7.5 10 12.5 MAX5497/MAX5499 37.5 50 62.5 VDD = 3V to 5.25V LSB ppm/°C MAX5496/MAX5498 Code = 0 LSB MAX5494/MAX5498 70 MAX5495/MAX5499 110 MAX5496/MAX5498, Code >128 0.1 MAX5497/MAX5499, Code >200 0.15 kΩ Ω % DIGITAL INPUTS (CS, SCLK, DIN) (Note 5) VDD = 3.6V to 5.25V 2.4 VDD = 2.7V to 3.6V 0.7 x VDD Dual-supply operation With respect to GND, VDD = 2.5V, VSS = -2.5V 2.0 Single-supply operation VDD = 2.7V to 5.25V 0.8 Dual-supply operation With respect to GND, VDD = 2.5V, VSS = -2.5V 0.6 Single-supply operation Input High Voltage VIH Input Low Voltage VIL Input Leakage Current IIN Input Capacitance CIN V V ±1 5 µA pF DYNAMIC CHARACTERISTICS Wiper -3dB Bandwidth BW Wiper at code 495 (01111 01111), 10pF load at wiper MAX5494/MAX5498 250 MAX5495/MAX5499 50 kHz _______________________________________________________________________________________ 3 MAX5494–MAX5499 ELECTRICAL CHARACTERISTICS (continued) MAX5494–MAX5499 10-Bit, Dual, Nonvolatile, Linear-Taper Digital Potentiometers ELECTRICAL CHARACTERISTICS (continued) (VDD = +2.7V to +5.25V, VSS = GND = 0, VH_ = VDD, VL_ = 0, TA = -40°C to +85°C, unless otherwise noted. Typical values are at VDD = +5.0V, TA = +25°C.) (Note 1) PARAMETER SYMBOL CONDITIONS MIN MAX5494/MAX5498; VDD = 3V; wiper at code 495; 10kHz, 1VRMS signal is applied at H_; 10pF load at wiper Total Harmonic Distortion TYP MAX 0.026 THD Analog Crosstalk UNITS % MAX5495/MAX5499; VDD = 3V; wiper at code 495; 10kHz, 1VRMS signal is applied at H_; 10pF load at wiper 0.03 CH2 = 11111 11111, CH1 = 01111 01111, CW_ = 10pF, VH1 = VDD = +2.5V, VL1 = VSS = -2.5V, measure VW1 with VW2 = 5VP-P at f = 1kHz -93 dB TA = +85°C 50 Years TA = +25°C 200,000 TA = +85°C 50,000 NONVOLATILE MEMORY RELIABILITY Data Retention Endurance Stores POWER SUPPLIES Single-Supply Voltage Dual-Supply Voltage Average Programming Current VDD VSS = GND = 0 2.70 5.25 VDD GND = 0 2.50 5.25 VSS (VDD - VSS) ≤ 5.25V -2.5 -0.2 IPG Peak Programming Current Standby Current 4 IDD During nonvolatile write only; digital inputs = VDD or GND During nonvolatile write only; digital inputs = VDD or GND Digital inputs = VDD or GND, TA = +25°C 220 400 4 0.6 _______________________________________________________________________________________ V V µA mA 1.5 µA 10-Bit, Dual, Nonvolatile, Linear-Taper Digital Potentiometers (VDD = +2.7V to +5.25V, VSS = GND = 0, VH_ = VDD, VL_ = 0, TA = -40°C to +85°C, unless otherwise noted. Typical values are at VDD = +5.0V, TA = +25°C.) (Note 1) PARAMETER SYMBOL CONDITIONS MIN TYP MAX UNITS ANALOG SECTION Wiper Settling Time (Note 6) tS MAX5494/MAX5498 5 MAX5495/MAX5499 22 µs SPI-COMPATIBLE SERIAL INTERFACE (Figure 6) SCLK Frequency SCLK Clock Period SCLK Pulse-Width High SCLK Pulse-Width Low CS Fall to SCLK Rise Setup SCLK Rise to CS Rise Hold DIN to SCLK Setup DIN Hold After SCLK SCLK Rise to CS Fall Delay CS Rise to SCLK Rise Hold CS Pulse-Width High Write NV Register Busy Time fSCLK tCP tCH tCL tCSS tCSH tDS tDH tCS0 tCS1 tCSW tBUSY 7 140 60 60 60 0 40 0 15 60 150 12 MHz ns ns ns ns ns ns ns ns ns ns ms Note 1: 100% production tested at TA = +25°C and TA = +85°C. Guaranteed by design to TA = -40°C. Note 2: The DNL and INL are measured for the voltage-divider with H_ = VDD and L_ = VSS. The wiper terminal (W_) is unloaded and measured with a high-input-impedance voltmeter. Note 3: The DNL and INL are measured with L_ = VSS = 0. For VDD = 5V, the wiper terminal is driven with a current source of IW = 80µA for the 50kΩ device and IW = 400µA for the 10kΩ device. For VDD = 3V, the wiper terminal is driven with a current source of IW = 40µA for the 50kΩ device and IW = 200µA for the 10kΩ device. Note 4: The wiper resistance is measured using the source currents given in Note 3. Note 5: The device draws higher supply current when the digital inputs are driven with voltages between (VDD - 0.5V) and (GND + 0.5V). See the Supply Current vs. Digital Input Voltage graph in the Typical Operating Characteristics. Note 6: Wiper settling test condition uses the voltage-divider with a 10pF load on W_. Transition code from 0 to 495 and measure the time from CS going high to the wiper voltage settling to within 0.5% of its final value. _______________________________________________________________________________________ 5 MAX5494–MAX5499 TIMING CHARACTERISTICS Typical Operating Characteristics (VDD = +5.0V, VSS = 0, TA = +25°C, unless otherwise noted.) VDD = 3V 1.0 0.8 0.6 0.4 0 DNL (LSB) 0.5 0.2 INL (LSB) 0 -0.2 -0.5 -0.4 -0.6 0 -0.2 -0.4 -0.6 -1.0 -0.8 -0.8 -1.5 -1.0 0 -1.0 0 128 256 384 512 640 768 896 1024 2.5 128 256 384 512 640 768 896 1024 3.0 3.5 4.0 4.5 CODE CODE VDD (V) MAXIMUM INTEGRAL NONLINEARITY vs. SUPPLY VOLTAGE (VARIABLE RESISTOR) DIFFERENTIAL NONLINEARITY vs. CODE (VOLTAGE-DIVIDER) INTEGRAL NONLINEARITY vs. CODE (VOLTAGE-DIVIDER) 0.5 VDD = 3V 0.8 1.5 MAX5494 toc05 1.0 MAX5494 toc04 1.0 0.6 VDD = 3V 1.0 0.4 -0.5 -1.0 0 0 -0.2 -0.5 -0.4 -0.6 -1.5 5.0 0.5 0.2 INL (LSB) DNL (LSB) 0 INL (LSB) 0.2 MAX5494 toc06 DNL (LSB) 0.4 MAX5494 toc03 0.6 1.0 MAX5494 toc02 VDD = 3V 0.8 1.5 MAX5494 toc01 1.0 MAXIMUM DIFFERENTIAL NONLINEARITY vs. SUPPLY VOLTAGE (VARIABLE RESISTOR) INTEGRAL NONLINEARITY vs. CODE (VARIABLE RESISTOR) DIFFERENTIAL NONLINEARITY vs. CODE (VARIABLE RESISTOR) -1.0 -0.8 -2.0 -1.5 -1.0 3.0 3.5 4.0 4.5 5.0 0 VDD (V) END-TO-END RESISTANCE vs. CODE (MAX5497/MAX5499) 70 END-TO-END RESISTANCE vs. CODE (MAX5496/MAX5498) 12 MAX5494 toc08 MAX5494 toc07 60 50 128 256 384 512 640 768 896 1024 CODE CODE WIPER RESISTANCE vs. CODE (VARIABLE RESISTOR) 80 0 128 256 384 512 640 768 896 1024 MAX5494 toc09 2.5 10 60 40 40 30 8 RWL (kΩ) RWL (kΩ) 50 RW (Ω) MAX5494–MAX5499 10-Bit, Dual, Nonvolatile, Linear-Taper Digital Potentiometers 30 6 20 4 10 2 20 10 0 0 0 128 256 384 512 640 768 896 1024 CODE 6 0 0 128 256 384 512 640 768 896 1024 CODE 0 128 256 384 512 640 768 896 1024 CODE _______________________________________________________________________________________ 10-Bit, Dual, Nonvolatile, Linear-Taper Digital Potentiometers END-TO-END RESISTANCE (RHL) % CHANGE vs. TEMPERATURE (VOLTAGE-DIVIDER) 19 18 17 0.4 0.2 0 -0.2 -0.4 -0.6 -0.8 -1.0 16 0 1 2 3 4 -15 STANDBY SUPPLY CURRENT vs. TEMPERATURE 0.4 0.2 0 -0.2 -0.4 -0.6 -0.8 10 35 60 85 -40 0.6 VDD = 5V 1000 100 160 120 100 80 60 40 10kΩ 35 60 85 TEMPERATURE (°C) VARIABLE RESISTOR TEMPERATURE COEFFICIENT vs. CODE 0 1 2 3 4 600 128 256 384 512 640 768 896 1024 DIGITAL INPUT VOLTAGE (V) CODE TAP-TO-TAP SWITCHING TRANSIENT (MAX5494/MAX5498) TAP-TO-TAP SWITCHING TRANSIENT (MAX5495/MAX5499) MAX5494 toc16 VDD = 3V TA = -40°C TO +85°C 0 5 MAX5494 toc17 700 50kΩ 0 0.1 10 85 140 20 -15 60 VOLTAGE-DIVIDER VDD = 3V TA = -40°C TO +85°C 180 1 0 35 200 10 0.3 10 RATIOMETRIC TEMPERATURE COEFFICIENT vs. CODE MAX5494 toc14 10,000 IDD (µA) 0.9 -40 -15 TEMPERATURE (°C) DIGITAL SUPPLY CURRENT vs. DIGITAL INPUT VOLTAGE MAX5494 toc13 VDD = 5.25V 1.2 IDD (µA) 0.6 TEMPERATURE (°C) WIPER VOLTAGE (V) 1.5 CODE IS 11 1111 1111 0.8 -1.0 -40 5 MAX5494 toc12 0.6 1.0 RATIOMETRIC TEMPCO (ppm/°C) RW (Ω) 20 0.8 MAX5494 toc15 21 1.0 MAX5494 toc11 VDD = 5V CODE IS 00 0000 0000 END-TO-END RESISTANCE CHANGE (%) MAX5494 toc10 22 WIPER-TO-END RESISTANCE (RWL) % CHANGE vs. TEMPERATURE (VARIABLE RESISTOR) WIPER-TO-END RESISTANCE CHANGE (%) WIPER RESISTANCE vs. WIPER VOLTAGE (VARIABLE RESISTOR) MAX5494–MAX5499 Typical Operating Characteristics (continued) (VDD = +5.0V, VSS = 0, TA = +25°C, unless otherwise noted.) MAX5494 toc18 CS 2V/div CS 2V/div TCVR (ppm/°C) 500 400 VW_ 20mV/div VW_ 20mV/div 300 H_ = VDD L_ = GND FROM CODE 01111 11111 TO CODE 10000 00000 CW_ = 10pF 200 50kΩ 10kΩ 100 H_ = VDD L_ = GND FROM CODE 01111 11111 TO CODE 10000 00000 CW_ = 10pF 0 0 128 256 384 512 640 768 896 1024 1µs/div 4µs/div CODE _______________________________________________________________________________________ 7 Typical Operating Characteristics (continued) (VDD = +5.0V, VSS = 0, TA = +25°C, unless otherwise noted.) CROSSTALK CROSSTALK vs. FREQUENCY VW2 2V/div 0 MAX5494 toc20 MAX5494 toc19 CW_ = 10pF CODE = 01111 01111 VW1 20mV/div CROSSTALK (dB) -20 VH2 = VDD VL2 = VL1 = VH1 = GND CW_ = 10pF -40 -60 -80 MAX5494/MAX5498 -100 MAX5495/MAX5499 -120 400ns/div 0.01 0.1 1 10 100 1000 FREQUENCY (kHz) THD+N vs. FREQUENCY (MAX5495/MAX5499) THD+N vs. FREQUENCY (MAX5494/MAX5498) CW_ = 10pF CODE = 01111 01111 1 THD+N (%) 0.1 0.01 0.1 0.01 0.001 0.001 0.0001 0.0001 0.01 0.1 1 10 0.01 100 0.1 WIPER RESPONSE vs. FREQUENCY (MAX5494/MAX5498) 0 -5 GAIN (dB) -10 CW_ = 30pF -15 -20 CW_ = 10pF -10 CW_ = 30pF -15 -20 CODE = 01111 01111 0.1 1 -25 10 FREQUENCY (kHz) 8 100 MAX5494 toc24 CW_ = 10pF -5 10 WIPER RESPONSE vs. FREQUENCY (MAX5495/MAX5499) MAX5494 toc23 0 1 FREQUENCY (kHz) FREQUENCY (kHz) -25 MAX5494 toc22 CW_ = 10pF CODE = 01111 01111 1 THD+N (%) 10 MAX5494 toc21 10 GAIN (dB) MAX5494–MAX5499 10-Bit, Dual, Nonvolatile, Linear-Taper Digital Potentiometers 100 1000 CODE = 01111 01111 0.1 1 10 100 1000 FREQUENCY (kHz) _______________________________________________________________________________________ 10-Bit, Dual, Nonvolatile, Linear-Taper Digital Potentiometers PIN MAX5494/ MAX5495 MAX5496/ MAX5497 MAX5498/ MAX5499 NAME FUNCTION 1 1 1 CS Active-Low Chip-Select Input. Drive CS low to enable the serial interface. Drive CS high to disable the serial interface and put the device in standby mode. 2 2 2 W2 Wiper Terminal 2 3 3 3 L2 Low Terminal 2 4 — — H2 High Terminal 2 5 5 5 VDD 6, 7,14,15 6, 7,14,15 6, 7,14,15 N.C. No Connection. Not internally connected. Positive Power-Supply Input. 2.7V ≤ VDD ≤ 5.25V. Bypass with a 0.1µF capacitor from VDD to GND as close to the device as possible 8 8 8 VSS Negative Power-Supply Input. Single-supply operation: VSS = GND = 0. Dual-supply operation: -2.5V ≤ VSS ≤ -0.2V (VSS can vary as long as (VDD - VSS) ≤ 5.25V). Bypass with a 0.1µF capacitor from VSS to GND as close to the device as possible. 9 — 9 H1 High Terminal 1 10 10 10 L1 Low Terminal 1 11 11 11 W1 Wiper Terminal 1 12 12 12 GND Ground 13 13 13 DIN Serial-Data Input. The data at DIN synchronously loads into the serial shift register on each SCLK rising edge. 16 16 16 SCLK Serial-Clock Input . SCLK clocks in the data when CS is low. — 4, 9 4 D.N.C Do Not Connect. Leave unconnected for proper operation. EP EP EP Exposed Pad Exposed Pad. Externally connect EP to VSS to provide a low thermal resistance path from the IC junction to the PC board or leave unconnected. _______________________________________________________________________________________ 9 MAX5494–MAX5499 Pin Descriptions 10-Bit, Dual, Nonvolatile, Linear-Taper Digital Potentiometers MAX5494–MAX5499 Functional Diagrams H1 VDD GND VSS CS SCLK DIN POR 2 x 10 BIT NVM 10-BIT LATCH 10 10-BIT LATCH 10 DECODER 1024 TAPS W1 SPI INTERFACE L1 H2 MAX5494 MAX5495 DECODER 1024 TAPS W2 L2 NOTE: THE PROGRAMMABLE VOLTAGE-DIVIDER IS NOT INTENDED FOR CURRENT TO FLOW THROUGH THE WIPER. NOTE: SEE THE MAX5494/MAX5495/MAX5498/MAX5499 PROGRAMMABLE VOLTAGE-DIVIDERS SECTION. Figure 1. MAX5494/MAX5495 Functional Diagram 10 ______________________________________________________________________________________ 10-Bit, Dual, Nonvolatile, Linear-Taper Digital Potentiometers VDD GND VSS 2 x 10 BIT NVM POR CS SCLK DIN 10-BIT LATCH 10 DECODER 1024 TAPS W1 L1 SPI INTERFACE 10-BIT LATCH 10 DECODER MAX5496 MAX5497 1024 TAPS W2 L2 Figure 2. MAX5496/MAX5497 Functional Diagram H1 VDD GND VSS CS SCLK DIN 2 x 10 BIT NVM POR 10-BIT LATCH 10 10-BIT LATCH 10 DECODER 1024 TAPS W1 SPI INTERFACE L1 MAX5498 MAX5499 DECODER 1024 TAPS W2 L2 NOTE: THE PROGRAMMABLE VOLTAGE-DIVIDER IS NOT INTENDED FOR CURRENT TO FLOW THROUGH THE WIPER. NOTE: SEE THE MAX5494/MAX5495/MAX5498/MAX5499 PROGRAMMABLE VOLTAGE-DIVIDERS SECTION. Figure 3. MAX5498/MAX5499 Functional Diagram ______________________________________________________________________________________ 11 MAX5494–MAX5499 Functional Diagrams (continued) Detailed Description The MAX5494–MAX5499 dual, nonvolatile, linear-taper, programmable voltage-dividers and variable resistors feature 1024 tap points (10-bit resolution) (see the Functional Diagrams). These devices consist of multiple strings of equal resistor segments with a wiper contact that moves among the 1024 effective tap points by a 3-wire SPI-compatible serial interface. The MAX5494/MAX5496/MAX5498 provide a total 10kΩ end-to-end resistance, and the MAX5495/MAX5497/ MAX5499 feature a 50kΩ end-to-end resistance. The MAX5494/MAX5495/MAX5498/MAX5499 allow access to the high, low, and wiper terminals for a standard voltage-divider configuration. Ensure that the terminal voltages fall between VSS and VDD. MAX5494/MAX5495/MAX5498/MAX5499 Programmable Voltage-Dividers The MAX5494/MAX5495/MAX5498/MAX5499 programmable voltage-dividers provide a weighted average of the voltage between the H_ and L_ inputs at the W_ output. The MAX5494/MAX5495/MAX5498/MAX5499 programmable voltage-divider network provides up to 1024 division ratios between the H_ and L_ voltage. Ideally, the VL voltage occurs at the wiper terminal when all data bits are zeros and the VH voltage occurs at the wiper terminal when all data bits are one (see the wiper voltage equation). The step-size voltage (1 LSB) is equal to the voltage applied across terminals H and L divided by 210. Calculate the wiper voltage VW as follows: where D is the decimal equivalent of the 10 data bits written (0 to 1023), VHL is the voltage difference between the H_ and L_ terminals, and: V VFSE = FSE HL 1024 V VZSE = ZSE HL 1024 The MAX5494/MAX5498 provide a 10kΩ end-to-end resistance value, while the MAX5495/MAX5499 feature a 50kΩ end-to-end resistance value. Note that the programmable voltage-divider is not intended to be used as a variable resistor. Wiper current creates a nonlinear voltage drop in series with the wiper. To ensure temperature drift remains within specifications, do not pull current through the voltage-divider wiper. Connect the wiper to a high-impedance node. Figures 4 and 5 show the behavior of the programmable voltage-divider resistance from W_ to H_ and W_ to L_, respectively. This does not apply to the variable-resistor devices. MAX5496–MAX5499 Variable Resistors The MAX5496–MAX5499 provide a programmable resistance from W_ to L_. The MAX5496/MAX5498 provide a 10kΩ end-to-end resistance value, while the MAX5497/MAX5499 feature a 50kΩ end-to-end resistance value. The programmable resolution of this 18 18 16 16 14 14 12 12 10 8 10 8 6 6 4 4 2 2 0 0 0 128 256 384 512 640 768 896 1024 CODE (DECIMAL) 50kΩ SCALES BY A FACTOR OF FIVE Figure 4. Resistance from W_ to H_ vs. Code (10kΩ VoltageDivider) 12 VHL − (| VFSE | + | VZSE |) D + VL + | VZSE | 1023 RW_L_ (kΩ) RW_H_ (kΩ) MAX5494–MAX5499 10-Bit, Dual, Nonvolatile, Linear-Taper Digital Potentiometers 0 128 256 384 512 640 768 896 1024 CODE (DECIMAL) 50kΩ SCALES BY A FACTOR OF FIVE Figure 5. Resistance from W_ to L_ vs. Code (10kΩ VoltageDivider) ______________________________________________________________________________________ 10-Bit, Dual, Nonvolatile, Linear-Taper Digital Potentiometers D RWL (D) = × RW−L + RZ 1023 where D is decimal equivalent of the 10 data bits written, RW-L is the nominal end-to-end resistance, and RZ is the zero-scale error. Table 1 shows RWL at selected codes. either eight clock cycles to transfer the command bits (Figure 7b) or 24 clock cycles with 16 bits disregarded by the device (Figure 7a). After the loading of data into the shift register, drive CS high to latch the data into the appropriate control register (specified by RA1 and RA0) and disable the serial interface. Keep CS low during the entire serial data stream to avoid corruption of the data. Table 2 shows the register map. Write Wiper Register The “write wiper register” command (C1, C0 = 00) controls the wiper positions. The 10 data bits (D9–D0) indicate the position of the wiper. For example, if DIN = 000000 0000, the wiper moves to the position closest to L_. If DIN = 11 1111 1111, the wiper moves closest to H_. Table 1. RWL at Selected Codes SPI-Compatible Serial Interface The MAX5494–MAX5499 use a 3-wire, SPI-compatible, serial data interface (Figure 6). This write-only interface contains three inputs: chip-select (CS), data input (DIN), and data clock (SCLK). Drive CS low to enable the serial interface and clock data synchronously into the shift register on each SCLK rising edge. The WRITE commands (C1, C0 = 00 or 01) require 24 clock cycles to transfer the command and data (Figure 7a). The COPY commands (C1, C0 = 10 or 11) use END-TO-END RESISTANCE VALUE CODE (DECIMAL) 10kΩ 50kΩ RWL (Ω) RWL (Ω) 0 70 110 1 80 160 512 5,070 25,110 1023 10,070 50,110 CS tCSW tCSS tCL tCSO tCH tCP tCSH tCS1 SCLK tDS tDH DIN Figure 6. SPI-Interface Timing Diagram ______________________________________________________________________________________ 13 MAX5494–MAX5499 resistance is equal to the nominal end-to-end resistance divided by 1024 (10-bit resolution). For example, the programmable resolution is 9.8Ω and 48.8Ω for the MAX5496/MAX5498 and the MAX5497/MAX5499, respectively. The 10-bit data in the 10-bit latch register selects the wiper position from the 1024 possible positions, resulting in 1024 values for the resistance from W_ to L_. Calculate the resistance from W_ to L_ (RWL) from the formula below: MAX5494–MAX5499 10-Bit, Dual, Nonvolatile, Linear-Taper Digital Potentiometers a) 24-BIT COMMAND/DATA WORD CS SCLK 1 2 3 4 5 6 8 9 RA1 RA0 D9 C1 C0 DIN 7 10 11 12 13 14 15 16 17 18 D8 D7 D6 D5 D4 D3 D2 D1 D0 19 20 21 22 23 24 b) 8-BIT COMMAND WORD CS SCLK 1 2 DIN 3 4 5 6 C1 C0 7 8 RA1 RA0 Figure 7. SPI-Compatible Serial-Interface Format Table 2. Register Map* 1 2 3 4 5 6 Bit Name CLOCK EDGE — — C1 C0 — — 7 Write Wiper Register 1 0 0 0 0 0 0 0 Write Wiper Register 2 0 0 0 0 0 0 Write NV Register 1 0 0 0 1 0 0 Write NV Register 2 0 0 0 1 0 Copy Wiper Register 1 to NV Register 1 0 0 1 0 Copy Wiper Register 2 to NV Register 2 0 0 1 Copy Wiper Register 1 to NV Register 1 and Copy Wiper Register 2 to NV Register 2 Simultaneously 0 0 Copy NV Register 1 to Wiper Register 1 0 Copy NV Register 2 to Wiper Register 2 Copy NV Register 1 to Wiper Register 1 and Copy NV Register 2 to Wiper Register 2 Simultaneously 8 9 10 11 12 13 14 15 16 17 18 … 24 D9 D8 D7 D6 D5 D4 D3 D2 D1 D0 — — 1 D9 D8 D7 D6 D5 D4 D3 D2 D1 D0 — — 1 0 D9 D8 D7 D6 D5 D4 D3 D2 D1 D0 — — 0 1 D9 D8 D7 D6 D5 D4 D3 D2 D1 D0 — — 0 1 0 D9 D8 D7 D6 D5 D4 D3 D2 D1 D0 — — 0 0 0 1 — — — — — — — — — — — — 0 0 0 1 0 — — — — — — — — — — — — 1 0 0 0 1 1 — — — — — — — — — — — — 0 1 1 0 0 0 1 — — — — — — — — — — — — 0 0 1 1 0 0 1 0 — — — — — — — — — — — — 0 0 1 1 0 0 1 1 — — — — — — — — — — — — RA1 RA0 *D9 is the MSB and D0 is the LSB of the data bits. 14 ______________________________________________________________________________________ 10-Bit, Dual, Nonvolatile, Linear-Taper Digital Potentiometers Write NV Register The “write NV register” command (C1, C0 = 01) stores the position of the wiper to the NV registers for use at power-up. Alternatively, the “copy wiper register to NV register” command writes to the NV register. Writing to the NV register does not affect the position of the wipers. The operation takes up to 12ms (max) after CS goes high to complete and no other operation should be performed until completion. Figure 9 shows how to write data to the NV register 1. Copy Wiper Register to NV Register The “copy wiper register to NV register” command (C1, C0 = 10) stores the current position of the wiper to the NV register for use at power-up. Figure 10 shows how to copy data from wiper register 1 to NV register 1. CS 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 SCLK C1 C0 DIN 0 0 0 RA1 RA0 0 0 0 0 1 D9 D8 D7 D6 D5 D4 D3 D2 D1 D0 X X X X X X WIPER REGISTER 1 UPDATED ACTION Figure 8. Write Wiper Register 1 CS 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 SCLK C1 C0 DIN 0 0 0 1 RA1 RA0 0 0 0 1 D9 D8 D7 D6 D5 D4 D3 D2 D1 D0 X X X X X X tBUSY WRITE NV REGISTER 1 (DEVICE IS BUSY) ACTION Figure 9. Write NV Register 1 ______________________________________________________________________________________ 15 MAX5494–MAX5499 The “write wiper register” command writes data to the volatile random access memory (RAM), leaving the NV registers unchanged. When the device powers up, the data stored in the NV registers transfers to the wiper register, moving the wiper to the stored position. Figure 8 shows how to write data to wiper register 1. MAX5494–MAX5499 10-Bit, Dual, Nonvolatile, Linear-Taper Digital Potentiometers Copy NV Register to Wiper Register The “copy NV register to wiper register” (C1, C0 = 11) restores the wiper position to the current value stored in the NV register. Figure 11 shows how to copy data from NV register 1 to wiper register 1. Standby Mode The MAX5494–MAX5499 feature a low-power standby mode. When the device is not being programmed, it enters into standby mode and supply current drops to 0.6µA (typ). Nonvolatile Memory The internal EEPROM consists of a nonvolatile register that retains the last value stored prior to power-down. The nonvolatile register is programmed to midscale at CS Power-Up Upon power-up, the MAX5494–MAX5499 load the data stored in the nonvolatile wiper register into the wiper register, updating the wiper position with the data stored in the nonvolatile wiper register. Applications Information The MAX5494–MAX5499 are intended for circuits requiring digitally controlled adjustable resistance, such as LCD contrast control (where voltage biasing adjusts the display contrast), or programmable filters with adjustable gain and/or cutoff frequency. CS 1 2 3 4 5 6 7 8 1 SCLK DIN the factory. The nonvolatile memory is guaranteed for 50 years for wiper data retention and up to 200,000 wiper write cycles. 2 3 4 5 6 7 8 RA1 RA0 0 1 SCLK 0 0 C1 C0 1 0 0 0 RA1 RA0 0 1 DIN 0 0 C1 C0 1 1 0 0 tBUSY ACTION WRITE NV REGISTER 1 (DEVICE IS BUSY) Figure 10. Copy Wiper Register 1 to NV Register 1 16 ACTION Figure 11. Copy NV Register 1 to Wiper Register 1 ______________________________________________________________________________________ WIPER REGISTER 1 UPDATED 10-Bit, Dual, Nonvolatile, Linear-Taper Digital Potentiometers R1 R2 1 fC = 2π × R3 × C G = 1+ Programmable Filter Figure 14 shows the configuration for a 1st-order programmable filter. The gain of the filter is adjusted by R2, and the cutoff frequency is adjusted by R3. Use the following equations to calculate the gain (G) and the 3dB cutoff frequency (fC). Gain and Offset Voltage Adjustment Figure 15 shows an application using the MAX5498/ MAX5499 to adjust the gain and nullify the offset voltage. 5V 5V H_ 30V 30V 1/2 MAX5494/MAX5495 1/2 MAX5498/MAX5499 W_ VOUT MAX480 MAX480 VOUT L_ 1/2 MAX5496–MAX5499 W_ L_ Figure 12. Positive LCD Bias Control Using a Voltage-Divider Figure 13. Positive LCD Bias Control Using a Variable Resistor C VREF VIN H_ VOUT 1/2 MAX5498/MAX5499 R3 1/2 MAX5496–MAX5499 W_ W_ R1 VOUT L_ L_ 1/2 MAX5496–MAX5499 R2 1/2 MAX5498/MAX5499 W_ W_ L_ Figure 14. Programmable Filter VIN L_ Figure 15. Gain- and Offset-Voltage Adjustment Circuit ______________________________________________________________________________________ 17 MAX5494–MAX5499 Positive LCD Bias Control Figures 12 and 13 show an application where the voltage-divider or variable resistor is used to make an adjustable, positive LCD-bias voltage. The op amp provides buffering and gain to the resistor-divider network. Selector Guide PART END-TO-END RESISTANCE (kΩ) CONFIGURATION MAX5494ETE Two programmable voltagedividers 10 MAX5495ETE Two programmable voltagedividers 50 MAX5496ETE Two variable resistors 10 MAX5497ETE Two variable resistors 50 MAX5498ETE One programmable voltagedivider and one variable resistor 10 MAX5499ETE One programmable voltagedivider and one variable resistor 50 Ordering Information (continued) PART PINPACKAGE TEMP RANGE MAX5496ETE -40°C to +85°C 16 TQFN-EP* T1655-2 -40°C to +85°C 16 TQFN-EP* T1655-2 MAX5498ETE -40°C to +85°C 16 TQFN-EP* T1655-2 MAX5499ETE -40°C to +85°C 16 TQFN-EP* T1655-2 *EP = Exposed pad. Chip Information TRANSISTOR COUNT: 32,262 PROCESS: BiCMOS GND W1 L1 H1 TOP VIEW 12 11 10 9 N.C. 14 N.C. 15 INTERFACE DIN 13 MAX5498 MAX5499 1 2 3 4 W2 L2 D.N.C. SCLK 16 8 VSS 7 N.C. 6 N.C. 5 VDD 5mm × 5mm × 0.8mm TQFN 18 PKG CODE MAX5497ETE Pin Configurations (continued) CS MAX5494–MAX5499 10-Bit, Dual, Nonvolatile, Linear-Taper Digital Potentiometers ______________________________________________________________________________________ 10-Bit, Dual, Nonvolatile, Linear-Taper Digital Potentiometers QFN THIN.EPS D2 D MARKING b C L 0.10 M C A B D2/2 D/2 k L XXXXX E/2 E2/2 C L (NE-1) X e E DETAIL A PIN # 1 I.D. e/2 E2 PIN # 1 I.D. 0.35x45° e (ND-1) X e DETAIL B e L1 L C L C L L L e e 0.10 C A C 0.08 C A1 A3 PACKAGE OUTLINE, 16, 20, 28, 32, 40L THIN QFN, 5x5x0.8mm -DRAWING NOT TO SCALE- 21-0140 H 1 2 ______________________________________________________________________________________ 19 MAX5494–MAX5499 Package Information (The package drawing(s) in this data sheet may not reflect the most current specifications. For the latest package outline information go to www.maxim-ic.com/packages.) MAX5494–MAX5499 10-Bit, Dual, Nonvolatile, Linear-Taper Digital Potentiometers Package Information (continued) (The package drawing(s) in this data sheet may not reflect the most current specifications. For the latest package outline information go to www.maxim-ic.com/packages.) COMMON DIMENSIONS PKG. 16L 5x5 20L 5x5 EXPOSED PAD VARIATIONS 28L 5x5 32L 5x5 40L 5x5 SYMBOL MIN. NOM. MAX. MIN. NOM. MAX. MIN. NOM. MAX. MIN. NOM. MAX. MIN. NOM. MAX. A A1 A3 b D E e k L L1 N ND NE JEDEC 0.70 0.75 0.80 0.70 0.75 0.80 0.70 0.75 0.80 0.70 0.75 0.80 0.70 0.75 0.80 0 0.02 0.05 0 0.02 0.05 0.20 REF. 0.20 REF. 0.25 0.30 0.35 0.25 0.30 0.35 4.90 5.00 5.10 4.90 5.00 5.10 4.90 5.00 5.10 4.90 5.00 5.10 0.80 BSC. 0.65 BSC. 0.25 - 0.25 - 0 0.02 0.05 0 0.02 0.05 0.20 REF. 0.20 REF. 0.20 0.25 0.30 4.90 5.00 5.10 4.90 5.00 5.10 0.50 BSC. 0.25 - 0.20 0.25 0.30 4.90 5.00 5.10 4.90 5.00 5.10 0.50 BSC. 0.25 - 0 0.02 0.05 0.20 REF. 0.15 0.20 0.25 4.90 5.00 5.10 4.90 5.00 5.10 0.40 BSC. 0.25 0.35 0.45 0.30 0.40 0.50 0.45 0.55 0.65 0.45 0.55 0.65 0.30 0.40 0.50 0.40 0.50 0.60 - 0.30 0.40 0.50 16 20 28 32 40 4 5 7 8 10 4 5 7 8 10 WHHB WHHC WHHD-1 WHHD-2 ----- NOTES: 1. DIMENSIONING & TOLERANCING CONFORM TO ASME Y14.5M-1994. 2. ALL DIMENSIONS ARE IN MILLIMETERS. ANGLES ARE IN DEGREES. 3. N IS THE TOTAL NUMBER OF TERMINALS. 4. THE TERMINAL #1 IDENTIFIER AND TERMINAL NUMBERING CONVENTION SHALL CONFORM TO JESD 95-1 SPP-012. DETAILS OF TERMINAL #1 IDENTIFIER ARE OPTIONAL, BUT MUST BE LOCATED WITHIN THE ZONE INDICATED. THE TERMINAL #1 IDENTIFIER MAY BE EITHER A MOLD OR MARKED FEATURE. D2 L E2 PKG. CODES MIN. NOM. MAX. T1655-1 T1655-2 T1655N-1 3.00 3.00 3.00 3.10 3.20 3.00 3.10 3.20 3.00 3.10 3.20 3.00 3.10 3.10 3.10 3.20 3.20 3.20 T2055-2 T2055-3 T2055-4 3.00 3.00 3.00 3.10 3.20 3.00 3.10 3.20 3.00 3.10 3.20 3.00 3.10 3.10 3.10 3.20 3.20 3.20 T2055-5 T2855-1 T2855-2 T2855-3 T2855-4 T2855-5 T2855-6 T2855-7 T2855-8 T2855N-1 T3255-2 T3255-3 T3255-4 T3255N-1 3.15 3.15 2.60 3.15 2.60 2.60 3.15 2.60 3.15 3.15 3.00 3.00 3.00 3.00 3.25 3.25 2.70 3.25 2.70 2.70 3.25 2.70 3.25 3.25 3.10 3.10 3.10 3.10 3.15 3.15 2.60 3.15 2.60 2.60 3.15 2.60 3.15 3.15 3.00 3.00 3.00 3.00 3.25 3.25 2.70 3.25 2.70 2.70 3.25 2.70 3.25 3.25 3.10 3.10 3.10 3.10 3.35 3.35 2.80 3.35 2.80 2.80 3.35 2.80 3.35 3.35 3.20 3.20 3.20 3.20 T4055-1 3.20 3.30 3.40 3.20 3.30 3.40 3.35 3.35 2.80 3.35 2.80 2.80 3.35 2.80 3.35 3.35 3.20 3.20 3.20 3.20 MIN. NOM. MAX. ±0.15 ** ** ** ** ** ** 0.40 DOWN BONDS ALLOWED NO YES NO NO YES NO YES ** NO NO YES YES NO ** ** 0.40 ** ** ** ** ** NO YES YES NO NO YES NO NO ** YES ** ** ** ** ** SEE COMMON DIMENSIONS TABLE 5. DIMENSION b APPLIES TO METALLIZED TERMINAL AND IS MEASURED BETWEEN 0.25 mm AND 0.30 mm FROM TERMINAL TIP. 6. ND AND NE REFER TO THE NUMBER OF TERMINALS ON EACH D AND E SIDE RESPECTIVELY. 7. DEPOPULATION IS POSSIBLE IN A SYMMETRICAL FASHION. 8. COPLANARITY APPLIES TO THE EXPOSED HEAT SINK SLUG AS WELL AS THE TERMINALS. 9. DRAWING CONFORMS TO JEDEC MO220, EXCEPT EXPOSED PAD DIMENSION FOR T2855-1, T2855-3, AND T2855-6. 10. WARPAGE SHALL NOT EXCEED 0.10 mm. 11. MARKING IS FOR PACKAGE ORIENTATION REFERENCE ONLY. 12. NUMBER OF LEADS SHOWN ARE FOR REFERENCE ONLY. 13. LEAD CENTERLINES TO BE AT TRUE POSITION AS DEFINED BY BASIC DIMENSION "e", ±0.05. PACKAGE OUTLINE, 16, 20, 28, 32, 40L THIN QFN, 5x5x0.8mm 21-0140 -DRAWING NOT TO SCALE- H 2 2 Maxim cannot assume responsibility for use of any circuitry other than circuitry entirely embodied in a Maxim product. No circuit patent licenses are implied. Maxim reserves the right to change the circuitry and specifications without notice at any time. 20 ____________________Maxim Integrated Products, 120 San Gabriel Drive, Sunnyvale, CA 94086 408-737-7600 © 2005 Maxim Integrated Products Printed USA is a registered trademark of Maxim Integrated Products, Inc.