19-3708; Rev 3; 4/07 10-Bit, Nonvolatile, Linear-Taper Digital Potentiometers ♦ 1024 Tap Positions ♦ Power-On Recall of Wiper Position from Nonvolatile Memory ♦ 16-Pin (3mm x 3mm x 0.8mm) TQFN or 14-Pin TSSOP Package ♦ 35ppm/°C End-to-End Resistance Temperature Coefficient ♦ 5ppm/°C Ratiometric Temperature Coefficient ♦ 10kΩ and 50kΩ End-to-End Resistor Values ♦ Pin-Selectable SPI-Compatible Serial Interface or Up/Down Digital Interface ♦ 1µA (max) Standby Current ♦ Single +2.7V to +5.25V Supply Operation ♦ Dual ±2.5V Supply Operation CS SCLK(INC) DIN(U/D) SPI/UD Pin Configurations 12 11 10 9 TOP VIEW 14 15 VSS 16 MAX5481* MAX5482* 1 2 PART PIN-PACKAGE MAX5481ETE 16 TQFN-EP* MAX5481EUD 14 TSSOP PKG CODE TOP MARK T1633F-3 ACP U14-1 — Note: All devices are specified over the -40°C to +85°C operating temperature range. 13 VDD 14 N.C. 15 VSS 16 SCLK(INC) DIN(U/D) SPI/UD 11 10 9 INTERFACE MAX5483 MAX5484 1 2 3 4 L Ordering Information GND 12 N.C. Pressure Sensors 7 N.C. 6 N.C. 5 N.C. 8 VSS 7 N.C. 6 N.C. 5 N.C. 4 CS Mechanical Potentiometer Replacement W LCD Contrast Adjustment VSS TQFN D.N.C. Low-Drift Programmable Gain Amplifiers 8 *SEE FUNCTIONAL DIAGRAM Applications Gain and Offset Adjustment 3 L VDD N.C. INTERFACE N.C. 13 H GND W The MAX5481–MAX5484 10-bit (1024-tap) nonvolatile, linear-taper, programmable voltage-dividers and variable resistors perform the function of a mechanical potentiometer, but replace the mechanics with a pinconfigurable 3-wire serial SPI™-compatible interface or up/down digital interface. The MAX5481/MAX5482 are 3-terminal voltage-dividers and the MAX5483/MAX5484 are 2-terminal variable resistors. The MAX5481–MAX5484 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. A pin-selectable up/down digital interface is also available. The MAX5481–MAX5484 are ideal for applications requiring digitally controlled potentiometers. Two end-toend resistance values are available (10kΩ and 50kΩ) in a voltage-divider or a variable-resistor configuration (see the Selector Guide). The nominal resistor temperature coefficient is 35ppm/°C end-to-end, and only 5ppm/°C ratiometric, making these devices ideal for applications requiring low-temperature-coefficient voltage-dividers, such as low-drift, programmable gain-amplifiers. The MAX5481–MAX5484 operate with either a +2.7V to +5.25V single power supply or ±2.5V dual power supplies. These devices consume 400µA (max) of supply current when writing data to the nonvolatile memory and 1.0µA (max) of standby supply current. The MAX5481–MAX5484 are available in a space-saving (3mm x 3mm), 16-pin TQFN, or a 14-pin TSSOP package and are specified over the extended (-40°C to +85°C) temperature range. Features TQFN Pin Configurations continued at end of data sheet. *EP = Exposed pad. Selector Guide appears at end of data sheet. Ordering Information continued at end of data sheet. SPI is a trademark of Motorola, Inc. ________________________________________________________________ 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 MAX5481–MAX5484 General Description MAX5481–MAX5484 10-Bit, Nonvolatile, Linear-Taper Digital Potentiometers ABSOLUTE MAXIMUM RATINGS VDD to GND ...........................................................-0.3V to +6.0V VSS to GND............................................................-3.5V to +0.3V VDD to VSS .............................................................-0.3V to +6.0V H, L, W to VSS ..................................(VSS - 0.3V) to (VDD + 0.3V) CS, SCLK(INC), DIN(U/D), SPI/UD to GND ..-0.3V to (VDD + 0.3V) Maximum Continuous Current into H, L, and W MAX5481/MAX5483.........................................................±5mA MAX5482/MAX5484......................................................±1.0mA Maximum Current into Any Other Pin ...............................±50mA Continuous Power Dissipation (TA = +70°C) 16-Pin TQFN (derate 17.5mW/°C above +70°C) .....1398.6mW 14-Pin TSSOP (derate 9.1mW/°C above +70°C) ..........727mW 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, unless otherwise noted.) (Note 1) PARAMETER SYMBOL CONDITIONS MIN DC PERFORMANCE (MAX5481/MAX5482 programmable voltage-divider) Resolution N VDD = 2.7V Integral Nonlinearity (Note 2) INL VDD = 5V VDD = 2.7V Differential Nonlinearity (Note 2) DNL VDD = 5V End-to-End Resistance Temperature Coefficient Zero-Scale Error ZSE End-to-End Resistance RH-L Wiper Capacitance CW Variable-Resistor Temperature Coefficient 2 TCVR LSB LSB 35 ppm/°C 5 ppm/°C MAX5481 -4 -2.5 0 MAX5482 -4 -0.75 0 MAX5481 0 +3.3 +5 MAX5482 0 +1.45 +5 MAX5481 7.5 10 12.5 MAX5482 37.5 50 62.5 60 W at code = 15, H and L shorted to VSS, measure Resistance from W to L and H resistance from W to H, Figures 1 and 2 DC PERFORMANCE (MAX5483/MAX5484 variable resistor) Resolution N VDD = 2.7V Integral Nonlinearity (Note 3) INL_R VDD = 3V VDD = 5V VDD = 2.7V Differential Nonlinearity (Note 3) DNL_R VDD = 3V VDD = 5V UNITS Bits ±2 ±2 ±1 ±1 Ratiometric Resistance Temperature Coefficient FSE MAX 10 TCR Full-Scale Error TYP MAX5481 6.3 MAX5482 25 LSB LSB kΩ pF kΩ VDD = 3V to 5.25V; code = 128 to 1024 10 -4 -4 -1 -1 Bits -1.6 -1.4 -1.3 +0.45 +0.4 +0.35 35 _______________________________________________________________________________________ +4 +4 LSB +1 +1 LSB ppm/°C 10-Bit, 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, unless otherwise noted.) (Note 1) PARAMETER Full-Scale Wiper-to-End Resistance SYMBOL RW-L MIN TYP MAX UNITS MAX5483 CONDITIONS 7.5 10 12.5 kΩ MAX5484 37.5 50 70 110 50 60 62.5 kΩ Zero-Scale Resistor Error RZ Code = 0 Wiper Resistance Wiper Capacitance RW CW VDD ≥ 3V (Note 4) MAX5483 MAX5484 Ω Ω pF DIGITAL INPUTS (CS, SCLK(INC), DIN(U/D), SPI/UD) (Note 5) Single-supply operation Input-High Voltage VIH Input-Low Voltage IIN Input Capacitance CIN 2.4 VDD = +2.7V to +3.6V 0.7 x VDD V Dual-supply operation VDD = +2.5V, VSS = -2.5V Single-supply operation VDD = +2.7V to +5.25V 0.8 Dual-supply operation VDD = +2.5V, VSS = -2.5V 0.6 VIL Input Leakage Current VDD = +3.6V to +5.25V 2.0 V ±1 5 µA pF DYNAMIC CHARACTERISTICS Wiper -3dB Bandwidth Wiper at code = 01111 01111, CLW = 10pF Total Harmonic Distortion VDD = 3V, wiper at code = 01111 01111, 1VRMS at 10kHz is applied at H, 10pF load on W THD MAX5481 250 MAX5482 50 MAX5481 0.026 MAX5482 0.03 kHz % NONVOLATILE MEMORY RELIABILITY Data Retention Endurance TA = +85°C 50 TA = +25°C 200,000 TA = +85°C 50,000 Years Stores POWER SUPPLY 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 During nonvolatile write; digital inputs = VDD or GND Peak Programming Current Standby Current IDD 220 During nonvolatile write only; digital inputs = VDD or GND 4 Digital inputs = VDD or GND, TA = +25°C 0.6 400 V V µA mA 1 µA _______________________________________________________________________________________ 3 MAX5481–MAX5484 ELECTRICAL CHARACTERISTICS (continued) MAX5481–MAX5484 10-Bit, Nonvolatile, Linear-Taper Digital Potentiometers TIMING 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, unless otherwise noted.) (Note 1) PARAMETER SYMBOL CONDITIONS MIN TYP MAX UNITS ANALOG SECTION Wiper Settling Time (Note 6) tS MAX5481 5 MAX5482 22 µs SPI-COMPATIBLE SERIAL INTERFACE (Figure 3) SCLK Frequency fSCLK 7 MHz SCLK Clock Period tCP 140 ns SCLK Pulse-Width High tCH 60 ns SCLK Pulse-Width Low tCL 60 ns CS Fall to SCLK Rise Setup tCSS 60 ns SCLK Rise to CS Rise Hold tCSH 0 ns DIN to SCLK Setup tDS 40 ns DIN Hold after SCLK tDH 0 ns SCLK Rise to CS Fall Delay tCS0 15 ns CS Rise to SCLK Rise Hold tCS1 60 ns CS Pulse-Width High tCSW 150 ns Write NV Register Busy Time tBUSY 12 ms UP/DOWN DIGITAL INTERFACE (Figure 8) CS to INC Setup tCI 25 ns INC High to U/D Change tID 20 ns U/D to INC Setup tDI 25 ns INC Low Period tIL 25 ns INC High Period tIH 25 ns INC Inactive to CS Inactive tIC 50 ns CS Deselect Time (Store) tCPH 50 ns INC Cycle Time tCYC 50 ns tIK 50 INC Active to CS Inactive Wiper Store Cycle tWSC ns 12 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 with the device configured as a 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_R and INL_R are measured with D.N.C. unconnected and L = VSS = 0. For VDD = 5V, the wiper terminal is driven with a source current of IW = 80µA for the 50kΩ device and 400µA for the 10kΩ device. For VDD = 3V, the wiper terminal is driven with a source current of 40µA for the 50kΩ device and 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 Supply Current vs. Digital Input Voltage in the Typical Operating Characteristics. Note 6: Wiper settling test condition uses the voltage-divider configuration with a 10pF load on W. Transition code from 00000 00000 to 01111 01111 and measure the time from CS going high to the wiper voltage settling to within 0.5% of its final value. 4 _______________________________________________________________________________________ 10-Bit, Nonvolatile, Linear-Taper Digital Potentiometers 0.2 0 0 -0.2 -0.4 -0.4 -0.6 -0.6 -0.8 -0.8 -1.0 1.0 128 256 384 512 640 768 896 1024 -1.0 -1.5 -2.0 0 CODE 0 128 256 384 512 640 768 896 1024 MAX5481 toc04 VDD = 3V DNL vs. CODE (MAX5481) INL vs. CODE (MAX5483) 2.0 VDD = 5V 1.5 1.0 1.0 0.5 0.5 1.0 MAX5481 toc05 INL vs. CODE (MAX5483) 128 256 384 512 640 768 896 1024 CODE CODE 2.0 1.5 0 -0.5 -1.0 0 0.5 VDD = 2.7V 0.8 0.6 MAX5481 toc06 0.2 VDD = 2.7V 1.5 INL (LSB) 0.4 INL vs. CODE (MAX5483) 2.0 MAX5481 toc03 0.6 0.4 -0.2 VDD = 5V 0.8 DNL (LSB) DNL (LSB) 0.6 MAX5481 toc01 VDD = 2.7V 0.8 DNL vs. CODE (MAX5483) 1.0 MAX5481 toc02 DNL vs. CODE (MAX5483) 1.0 0 -0.5 -0.5 -1.0 -1.0 -1.5 -1.5 -2.0 -2.0 128 256 384 512 640 768 896 1024 -0.6 -0.8 -1.0 0 CODE DNL vs. CODE (MAX5481) INL vs. CODE (MAX5481) VDD = 2.7V 0.8 0.6 INL vs. CODE (MAX5481) 0.6 0.2 0.2 -0.2 INL (LSB) 0.4 0.2 0 -0.2 0 -0.2 -0.4 -0.4 -0.4 -0.6 -0.6 -0.6 -0.8 -0.8 -0.8 -1.0 -1.0 0 128 256 384 512 640 768 896 1024 CODE VDD = 5V 0.8 0.4 0 128 256 384 512 640 768 896 1024 1.0 0.4 INL (LSB) DNL (LSB) 0 CODE 1.0 MAX5481 toc07 VDD = 5V 0.6 128 256 384 512 640 768 896 1024 CODE 1.0 0.8 0 -0.2 -0.4 MAX5481 toc08 0 0.2 MAX5481 toc09 0 DNL (LSB) INL (LSB) INL (LSB) 0.4 -1.0 0 128 256 384 512 640 768 896 1024 CODE 0 128 256 384 512 640 768 896 1024 CODE _______________________________________________________________________________________ 5 MAX5481–MAX5484 Typical Operating Characteristics (VDD = 5.0V, VSS = 0, TA = +25°C, unless otherwise noted.) Typical Operating Characteristics (continued) (VDD = 5.0V, VSS = 0, TA = +25°C, unless otherwise noted.) 0.6 0.2 0.2 0 -0.2 0 -0.2 -0.4 -0.4 -0.4 -0.6 -0.6 -0.6 -0.8 -0.8 -0.8 -1.0 -1.0 128 256 384 512 640 768 896 1024 -1.0 0 0 CODE 0.6 DNL vs. CODE (MAX5482) 1.0 MAX5481 toc13 VDD = 5V VDD = 2.7V 0.8 0.6 DNL vs. CODE (MAX5482) 1.0 0.6 0.2 0.2 -0.2 DNL (LSB) 0.4 0.2 DNL (LSB) 0.4 0 -0.2 0 -0.2 -0.4 -0.4 -0.4 -0.6 -0.6 -0.6 -0.8 -0.8 -0.8 -1.0 -1.0 128 256 384 512 640 768 896 1024 128 256 384 512 640 768 896 1024 0 128 256 384 512 640 768 896 1024 CODE CODE CODE INL vs. CODE (MAX5482) INL vs. CODE (MAX5482) WIPER RESISTANCE vs. CODE (VARIABLE RESISTOR, TA = -40°C) 0.6 0.4 0.2 0.2 INL (LSB) 0.4 0 -0.2 -0.4 -0.4 -0.6 -0.6 -0.8 -0.8 -1.0 -1.0 CODE 80 70 60 50 0 -0.2 128 256 384 512 640 768 896 1024 VDD = 5V 0.8 MAX5481 toc18 0.6 1.0 RW (Ω) VDD = 2.7V 0.8 MAX5481 toc17 1.0 0 -1.0 0 MAX5481 toc16 0 VDD = 5V 0.8 0.4 0 128 256 384 512 640 768 896 1024 CODE MAX5481 toc14 INL vs. CODE (MAX5484) 1.0 0.8 128 256 384 512 640 768 896 1024 MAX5481 toc15 -0.2 INL (LSB) 0.4 0.2 CODE INL (LSB) 0.6 0.4 0 VDD = 2.7V 0.8 0.4 0 6 INL vs. CODE (MAX5484) 1.0 MAX5481 toc12 VDD = 5V 0.8 DNL (LSB) DNL (LSB) 0.6 MAX5481 toc10 VDD = 2.7V 0.8 DNL vs. CODE (MAX5484) 1.0 MAX5481 toc11 DNL vs. CODE (MAX5484) 1.0 INL (LSB) MAX5481–MAX5484 10-Bit, Nonvolatile, Linear-Taper Digital Potentiometers 40 30 20 10 0 128 256 384 512 640 768 896 1024 CODE 0 0 128 256 384 512 640 768 896 1024 CODE _______________________________________________________________________________________ 10-Bit, Nonvolatile, Linear-Taper Digital Potentiometers 70 50 40 30 20 20 10 10 128 256 384 512 640 768 896 1024 10 0 0 128 256 384 512 640 768 896 1024 0 128 256 384 512 640 768 896 1024 CODE CODE W-TO-L RESISTANCE vs. CODE (MAX5483) WIPER RESISTANCE vs. WIPER VOLTAGE (VARIABLE RESISTOR) END-TO-END (RHL) % CHANGE vs. TEMPERATURE (VOLTAGE-DIVIDER) 21.0 10 20.5 RW (Ω) 8 6 20.0 19.5 4 19.0 2 18.5 0 2.0 18.0 128 256 384 512 640 768 896 1024 MAX5481 toc24 VDD = 5V CODE = 00 0000 21.5 END-TO-END RESISTANCE CHANGE (%) MAX5481 toc23 22.0 MAX5481 toc22 12 1.5 1.0 0.5 0 -0.5 -1.0 -1.5 -2.0 0 1 2 3 4 5 -40 -15 10 35 60 WIPER VOLTAGE (V) TEMPERATURE (°C) WIPER-TO-END RESISTANCE (RWL) % CHANGE vs. TEMPERATURE (VARIABLE RESISTOR) STANDBY SUPPLY CURRENT vs. TEMPERATURE DIGITAL SUPPLY CURRENT vs. DIGITAL INPUT VOLTAGE VDD = 5.25V 1.2 1.0 IDD (µA) 0.5 0 -0.5 -1.0 0.9 85 10,000 VDD = 5V 1000 IDD (µA) 1.5 1.5 MAX5481 toc25 CODE = 11 1111 1111 MAX5481 toc26 CODE 2.0 WIPER-TO-END RESISTANCE CHANGE (%) 30 CODE 14 0 40 20 0 0 RWL (kΩ) 40 30 0 50 MAX5481 toc27 50 60 RWL (kΩ) 60 RW (Ω) 60 70 MAX5481 toc20 70 RW (Ω) 80 MAX5481 toc19 80 W-TO-L RESISTANCE vs. CODE (MAX5484) WIPER RESISTANCE vs. CODE (VARIABLE RESISTOR, TA = +85°C) MAX5481 toc21 WIPER RESISTANCE vs. CODE (VARIABLE RESISTOR, TA = +25°C) 100 0.6 10 0.3 1 -1.5 -2.0 0.1 0 -40 -15 10 35 TEMPERATURE (°C) 60 85 -40 -15 10 35 TEMPERATURE (°C) 60 85 0 0.5 1.0 1.5 2.0 2.5 3.0 3.5 4.0 4.5 5.0 DIGITAL INPUT VOLTAGE (V) _______________________________________________________________________________________ 7 MAX5481–MAX5484 Typical Operating Characteristics (continued) (VDD = 5.0V, VSS = 0, TA = +25°C, unless otherwise noted.) Typical Operating Characteristics (continued) (Circuit of Figure 1, TA = +25°C, unless otherwise noted.) TAP-TO-TAP SWITCHING TRANSIENT RESPONSE (MAX5482) TAP-TO-TAP SWITCHING TRANSIENT RESPONSE (MAX5481) MAX5481 toc29 MAX5481 toc28 CS 2V/div CS 2V/div VW (AC-COUPLED) 20mV/div VW (AC-COUPLED) 20mV/div H = VDD, L = GND CW = 10pF FROM CODE 01 1111 1111 TO CODE 10 0000 0000 H = VDD, L = GND CW = 10pF FROM CODE 01 1111 1111 TO CODE 10 0000 0000 4µs/div 1µs/div WIPER RESPONSE vs. FREQUENCY (MAX5482) CW = 30pF -10 CW = 30pF -15 -15 -20 -20 100 0.0001 0.1 1000 1 10 100 1000 0.01 0.1 1 10 100 FREQUENCY (kHz) FREQUENCY (kHz) FREQUENCY (kHz) THD+N vs. FREQUENCY (MAX5482) RATIOMETRIC TEMPERATURE COEFFICIENT vs. CODE VARIABLE-RESISTOR TEMPERATURE COEFFICIENT vs. CODE 0.1 0.01 0.001 VOLTAGE-DIVIDER VDD = +3V TA = -40°C TO +85°C 180 160 0.1 1 FREQUENCY (kHz) 10 100 VDD = +3V TA = -40°C TO +85°C 600 500 140 120 100 80 60 400 300 200 40 50kΩ 20 0.0001 700 TCVR (ppm) 1 200 RATIOMETRIC TEMPCO (ppm) MAX5481 toc33 CODE 01111 01111 CW = 10pF 8 0.01 MAX5481 toc35 10 10 0.01 0.1 CODE = 01111 01111 -25 1 1 0.001 CODE = 01111 01111 -25 0.1 CODE 01111 01111 CW = 10pF THD+N (%) -10 CW = 10pF MAX5481 toc32 -5 10 MAX5481 toc34 GAIN (dB) -5 GAIN (dB) CW = 10pF 0 MAX5481 toc30 0 THD+N vs. FREQUENCY (MAX5481) MAX5481 toc31 WIPER RESPONSE vs. FREQUENCY (MAX5481) THD+N (%) MAX5481–MAX5484 10-Bit, Nonvolatile, Linear-Taper Digital Potentiometers 50kΩ 10kΩ 10kΩ 100 0 0 0 128 256 384 512 640 768 896 1024 0 128 256 384 512 640 768 896 1024 CODE _______________________________________________________________________________________ CODE 10-Bit, Nonvolatile, Linear-Taper Digital Potentiometers (MAX5481/MAX5482 Voltage-Dividers) PIN NAME FUNCTION TQFN TSSOP 1 12 H High Terminal 2 11 W Wiper Terminal 3 10 L Low Terminal 4–7, 15 7, 8, 9, 13 N.C. No Connection. Not internally connected. 8, 16 14 VSS Negative Power-Supply Input. For single-supply operation, connect VSS to GND. For dualsupply operation, -2.5V ≤ VSS ≤ -0.2V as long as (VDD - VSS) ≤ +5.25V. Bypass VSS to GND with a 0.1µF ceramic capacitor as close to the device as possible. 9 6 SPI/UD Interface-Mode Select. Select serial SPI interface when SPI/UD = 1. Select serial up/down interface when SPI/UD = 0. Serial SPI Interface Data Input (SPI/UD = 1) Up/Down Control Input (SPI/UD = 0). With DIN(U/D) low, a high-to-low SCLK(INC) transition decrements the wiper position. With DIN(U/D) high, a high-to-low SCLK(INC) transition increments the wiper position. 10 5 DIN(U/D) 11 4 SCLK(INC) 12 3 CS 13 2 GND Ground Positive Power-Supply Input (+2.7V ≤ VDD ≤ +5.25V). Bypass VDD to GND with a 0.1µF ceramic capacitor as close to the device as possible. Serial SPI Interface Clock Input (SPI/UD = 1) 14 1 VDD EP — EP Wiper-Increment Control Input (SPI/UD = 0). With CS low, the wiper position moves in the direction determined by the state of DIN(U/D) on a high-to-low transition. Active-Low Digital Input Chip Select Exposed Pad. Externally connect EP to VSS or leave unconnected. _______________________________________________________________________________________ 9 MAX5481–MAX5484 Pin Description MAX5481–MAX5484 10-Bit, Nonvolatile, Linear-Taper Digital Potentiometers Pin Description (continued) (MAX5483/MAX5484 Variable Resistors) PIN NAME FUNCTION TQFN TSSOP 4–7, 15 7, 8, 9, 13 N.C. 1 12 D.N.C. 2 11 W Wiper Terminal 3 10 L Low Terminal 8, 16 14 VSS Negative Power-Supply Input. For single-supply operation, connect VSS to GND. For dualsupply operation, -2.5V ≤ VSS ≤ -0.2V as long as (VDD - VSS) ≤ 5.25V. Bypass VSS to GND with a 0.1µF ceramic capacitor as close to the device as possible. 9 6 SPI/UD Interface-Mode Select. Select serial SPI interface when SPI/UD = 1. Select serial up/down interface when SPI/UD = 0. No Connection. Not internally connected. Do Not Connect. Leave unconnected for proper operation. Serial SPI Interface Data Input (SPI/UD = 1) 10 5 DIN(U/D) Up/Down Control Input (SPI/UD = 0). With DIN(U/D) low, a high-to-low SCLK(INC) transition decrements the wiper position. With DIN(U/D) high, a high-to-low SCLK(INC) transition increments the wiper position. Serial SPI Interface Clock Input (SPI/UD = 1) 10 11 4 SCLK(INC) 12 3 CS 13 2 GND Ground Positive Power-Supply Input (+2.7V ≤ VDD ≤ +5.25V). Bypass VDD to GND with a 0.1µF ceramic capacitor as close to the device as possible. 14 1 VDD EP — EP Wiper Increment Control Input (SPI/UD = 0). With CS low, the wiper position moves in the direction determined by the state of DIN(U/D) on a high-to-low transition. Active-Low Digital Input Chip Select Exposed Pad. Externally connect EP to VSS or leave unconnected. ______________________________________________________________________________________ 10-Bit, Nonvolatile, Linear-Taper Digital Potentiometers H VDD GND VSS 10-BIT NV MEMORY 10-BIT LATCH 10 10 DECODER W CS POR SCLK(INC) SPI INTERFACE DIN(U/D) L MUX UP/DOWN INTERFACE SPI/UD MAX5481 MAX5482 NOTE: THE MAX5481/MAX5482 ARE NOT INTENDED FOR CURRENT TO FLOW THROUGH THE WIPER (SEE THE MAX5481/MAX5482 PROGRAMMABLE VOLTAGE-DIVIDER SECTION). ______________________________________________________________________________________ 11 MAX5481–MAX5484 Functional Diagrams 10-Bit, Nonvolatile, Linear-Taper Digital Potentiometers MAX5481–MAX5484 Functional Diagrams (continued) VDD GND VSS 10-BIT NV MEMORY 10 10-BIT LATCH 10 DECODER H L CS POR SCLK(INC) SPI INTERFACE DIN(U/D) MUX UP/DOWN INTERFACE SPI/UD MAX5483 MAX5484 Detailed Description The MAX5481/MAX5482 linear programmable voltagedividers and the MAX5483/MAX5484 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 points through a pin-selectable 3-wire SPI-compatible serial interface or up/down interface. The MAX5481/MAX5483 provide a total end-to-end resistance of 10kΩ, and the MAX5482/MAX5484 have an end-to-end resistance of 50kΩ. The MAX5481/MAX5482 allow access to the high, low, and wiper terminals for a standard voltagedivider configuration. 12 MAX5481/MAX5482 Programmable Voltage-Dividers The MAX5481/MAX5482 programmable voltagedividers provide a weighted average of the voltage between the H and L inputs at the W output. Both devices feature 10-bit resolution and provide up to 1024 tap points between the H and L voltages. Ideally, the VL voltage occurs at the wiper terminal (W) when all data bits are zero and the VH voltage occurs at the wiper terminal when all data bits are one. The step size (1 LSB) voltage is equal to the voltage applied across terminals H and L divided by 210. Calculate the wiper voltage VW as follows: ( ) V HL − VFSE +VZSE + V +VZSE VW (D) = D L 1023 ______________________________________________________________________________________ 18 16 16 14 14 12 12 RW-L (kΩ) 18 10 8 10 8 6 6 4 4 2 2 0 0 0 0 128 256 384 512 640 768 896 1024 128 256 384 512 640 768 896 1024 CODE (DECIMAL) 50kΩ DEVICE SCALES BY A FACTOR OF FIVE CODE (DECIMAL) 50kΩ DEVICE SCALES BY A FACTOR OF FIVE Figure 1. Resistance from W to H vs. Code (10kΩ Voltage-Divider) Figure 2. Resistance from W to L vs. Code (10kΩ Voltage-Divider) 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: Table 1. RWL at Selected Codes V VFSE = FSE HL ,and 1024 V VZSE = ZSE HL 1024 The MAX5481 includes a total end-to-end resistance value of 10kΩ while the MAX5482 features an end-toend resistance value of 50kΩ. These devices are 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 1 and 2 show the behavior of the MAX5481’s resistance from W to H and from W to L. This does not apply to the variable-resistor devices MAX5483/MAX5484 Variable Resistors The MAX5483/MAX5484 provide a programmable resistance between W and L. The MAX5483 features a total end-to-end resistance value of 10kΩ, while the MAX5484 provides an end-to-end resistance value of 50kΩ. The programmable resolution of this resistance is equal to the nominal end-to-end resistance divided by 1024 (10-bit resolution). For example, each nominal segment resistance is 9.8Ω and 48.8Ω for the MAX5483 and the MAX5484, respectively. CODE (DECIMAL) MAX5483 (10kΩ DEVICE) MAX5484 (50kΩ DEVICE) RWL (Ω) RWL (Ω) 0 70 110 1 80 160 512 5070 25,110 1023 10,070 50,110 The 10-bit data in the 10-bit latch register selects a 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) by using the following formula: RWL (D) = 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 the values of RWL at selected codes for the MAX5483/MAX5484. Digital Interface Configure the MAX5481–MAX5484 by a pin-selectable, 3-wire, SPI-compatible serial data interface or an up/down interface. Drive SPI/UD high to select the 3wire SPI-compatible interface. Pull SPI/UD low to select the up/down interface. ______________________________________________________________________________________ 13 MAX5481–MAX5484 RW-H (kΩ) 10-Bit, Nonvolatile, Linear-Taper Digital Potentiometers MAX5481–MAX5484 10-Bit, Nonvolatile, Linear-Taper Digital Potentiometers Table 2. Command Decoding* CLOCK EDGE 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 Bit Name — — C1 C0 — — — — D9 D8 D7 D6 D5 D4 D3 D2 Write Wiper Register 0 0 0 0 0 0 0 0 D9 D8 D7 D6 D5 D4 D3 D2 Copy Wiper Register to NV Register 0 0 1 0 0 0 0 0 — — — — — — — — Copy NV Register to Wiper Register 0 0 1 1 0 0 0 0 — — — — — — — — 17 18 19 … 24 D1 D0 D1 D0 — … — X … X — — — … — — — — … — *D9 is the MSB and D0 is the LSB. X = Don’t care. CS tCSW tCSS tCL tCSO tCP tCH tCSH tCS1 SCLK(INC) tDS tDH DIN(U/D) Figure 3. SPI-Compatible Serial-Interface Timing Diagram (SPI/UD = 1) SPI-Compatible Serial Interface Drive SPI/UD high to enable the 3-wire SPI-compatible serial interface (see Figure 3). This write-only interface contains three inputs: chip select (CS), data in (DIN(U/D)), and data clock (SCLK(INC)). Drive CS low to load the data at DIN(U/D) synchronously into the shift register on each SCLK(INC) rising edge. The WRITE command (C1, C0 = 00) requires 24 clock cycles to transfer the command and data (Figure 4a). The COPY commands (C1, C0 = 10 or 11) use either eight clock cycles to transfer the command bits (Figure 4b) or 24 clock cycles with the last 16 data bits disregarded by the device. Write Wiper Register Data written to this register (C1, C0 = 00) controls the wiper position. The 10 data bits (D9–D0) indicate the position of the wiper. For example, if DIN(U/D) = 00 0000 0000, the wiper moves to the position closest to L. If DIN(U/D) = 11 1111 1111, the wiper moves closest to H. This command writes data to the volatile random access memory (RAM), leaving the NV register unchanged. When the device powers up, the data stored in the NV register transfers to the wiper register, moving the wiper to the stored position. Figure 5 shows how to write data to the wiper register. After loading the data into the shift register, drive CS high to latch the data into the appropriate control register. Keep CS low during the entire serial data stream to avoid corruption of the data. Table 2 shows the command decoding. 14 ______________________________________________________________________________________ 10-Bit, Nonvolatile, Linear-Taper Digital Potentiometers MAX5481–MAX5484 a) 24-BIT COMMAND/DATA WORD CS SCLK(INC) 1 2 3 4 5 6 7 8 C1 C0 DIN(U/D) 9 10 11 12 13 14 15 16 17 18 D9 D8 D7 D6 D5 D4 D3 D2 D1 D0 19 20 23 24 19 20 21 22 23 21 22 b) 8-BIT COMMAND WORD CS SCLK(INC) 1 2 3 4 5 6 7 8 C1 C0 DIN(U/D) Figure 4. Serial SPI-Compatible Interface Format CS 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 24 SCLK(INC) C1 C0 DIN(U/D) 0 0 0 0 0 0 0 0 D9 D8 D7 D6 D5 D4 D3 D2 D1 D0 X X X X X X WIPER REGISTER UPDATED ACTION Figure 5. Write Wiper Register Operation ______________________________________________________________________________________ 15 MAX5481–MAX5484 10-Bit, Nonvolatile, Linear-Taper Digital Potentiometers Table 3. Truth Table CS DIN(U/D) SCLK(INC) W L L ↓ Decrement L H ↓ Increment L X ↑ No Change H X X No Change ↓ X X No Change ↑ X L Position Not Stored ↑ X H Position Stored CS 1 2 3 4 5 6 7 8 SCLK(INC) DIN(U/D) 0 0 C1 C0 1 0 0 0 0 0 tBUSY ↑ = High-to-low transition. WRITE NV REGISTER (DEVICE IS BUSY) ↓ = Low-to-high transition. ACTION X = Don’t care. 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 6 shows how to copy data from wiper register to NV register. The operation takes up to 12ms (max) after CS goes high to complete and no other operation should be performed until completion. 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 7 shows how to copy data from the NV register to the wiper register. Figure 6. Copy Wiper Register to NV Register Operation CS 1 2 3 4 5 6 7 8 SCLK(INC) DIN(U/D) 0 0 C1 C0 1 1 0 0 0 0 Digital Up/Down Interface Figure 8 illustrates an up/down serial-interface timing diagram. In digital up/down interface mode (SPI/UD = 0), the logic inputs CS, DIN(U/D), and SCLK(INC) control the wiper position and store it in nonvolatile memory (see Table 3). The chip-select (CS) input enables the serial interface when low and disables the interface when high. The position of the wiper is stored in the nonvolatile register when CS transitions from low to high while SCLK(INC) is high. When the serial interface is active (CS low), a high-tolow (falling edge) transition on SCLK(INC) increments or decrements the internal 10-bit counter depending on the state of DIN(U/D). If DIN(U/D) is high, the wiper increments. If DIN(U/D) is low, the wiper decrements. The device stores the value of the wiper position in the nonvolatile memory when CS transitions from low to high while SCLK(INC) is high. The host system can disable 16 ACTION WIPER REGISTER UPDATED Figure 7. Copy NV Register to Wiper Register Operation the serial interface and deselect the device without storing the latest wiper position in the nonvolatile memory by keeping SCLK(INC) low while taking CS high. Upon power-up, the MAX5481–MAX5484 load the value of nonvolatile memory into the wiper register, and set the wiper position to the value last stored. ______________________________________________________________________________________ 10-Bit, Nonvolatile, Linear-Taper Digital Potentiometers Applications Information The MAX5481–MAX5484 are ideal 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. 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 the factory. The nonvolatile memory is guaranteed for 50 years of wiper data retention and up to 200,000 wiper write cycles. Positive LCD Bias Control Figures 9 and 10 show an application where a voltagedivider or a variable resistor is used to make an adjustable, positive LCD-bias voltage. The op amp provides buffering and gain to the voltage-divider network made by the programmable voltage-divider (Figure 9) or to a fixed resistor and a variable resistor (see Figure 10). Power-Up Upon power-up, the MAX5481–MAX5484 load the data stored in the nonvolatile wiper register into the volatile wiper register, updating the wiper position with the data stored in the nonvolatile wiper register. Programmable Gain and Offset Adjustment Figure 11 shows an application where a voltage-divider and a variable resistor are used to make a programmable gain and offset adjustment. WIPER POSITION STORED WIPER POSITION NOT STORED CS tCYC tCI tIC tIK tCPH tIH tIL SCLK(INC) tID tDI tWSC DIN(U/D) tS VW NOTES: VW IS NOT A DIGITAL SIGNAL. IT REPRESENTS A WIPER TRANSITION. SCLK(INC) MUST BE AT LOGIC HIGH WHEN DIN(U/D) CHANGES STATE. Figure 8. Up/Down Serial-Interface Timing Diagram (SPI/UD = 0) ______________________________________________________________________________________ 17 MAX5481–MAX5484 Standby Mode The MAX5481–MAX5484 feature a low-power standby mode. When the device is not being programmed, it enters into standby mode and supply current drops to 0.5µA (typ). MAX5481–MAX5484 10-Bit, Nonvolatile, Linear-Taper Digital Potentiometers VREF 5V H H 30V MAX5481 MAX5482 MAX5481 MAX5482 W MAX480 W VOUT VOUT L L MAX5483 MAX5484 W L VIN Figure 9. Positive LCD Bias Control Using a Voltage-Divider Figure 11. Programmable Gain/Offset Adjustment C 5V VIN VOUT 30V MAX480 VOUT R3 MAX5483 MAX5484 W L MAX5483 MAX5484 W MAX5483 MAX5484 L R2 W L Figure 10. Positive LCD Bias Control Using a Variable Resistor Programmable Filter Figure 12 shows the configuration for a 1st-order programmable filter using two variable resistors. Adjust R2 for the gain and adjust R3 for the cutoff frequency. Use the following equations to estimate the gain (G) and the 3dB cutoff frequency (fC): 18 Figure 12. Programmable Filter R1 G = 1+ R2 fC = 1 2π × R3 × C ______________________________________________________________________________________ R1 10-Bit, Nonvolatile, Linear-Taper Digital Potentiometers PART CONFIGURATION END-TO-END RESISTANCE (kΩ) Ordering Information (continued) PART PIN-PACKAGE MAX5481ETE Voltage-divider 10 MAX5482ETE 16 TQFN-EP* MAX5481EUD Voltage-divider 10 MAX5482EUD 14 TSSOP MAX5482ETE Voltage-divider 50 MAX5483ETE 16 TQFN-EP* PKG CODE TOP MARK T1633F-3 ACQ U14-1 — T1633F-3 ACR MAX5482EUD Voltage-divider 50 MAX5483EUD 14 TSSOP MAX5483ETE Variable resistor 10 MAX5484ETE 16 TQFN-EP* MAX5483EUD Variable resistor 10 MAX5484EUD 14 TSSOP Note: All devices are specified over the -40°C to +85°C operating temperature range. MAX5484ETE Variable resistor 50 MAX5484EUD Variable resistor 50 U14-1 — T1633F-3 ACS U14-1 — *EP = Exposed pad. Chip Information TRANSISTOR COUNT: 20,029 PROCESS: BiCMOS Pin Configurations (continued) TOP VIEW VDD 1 14 VSS VDD 1 14 VSS GND 2 13 N.C. GND 2 13 N.C. CS 3 12 H CS 3 12 D.N.C. SCLK(INC) 4 DIN(U/D) 5 MAX5481* MAX5482* 11 W SCLK(INC) 4 10 L DIN(U/D) 5 MAX5483 MAX5484 11 W 10 L SPI/UD 6 9 N.C. SPI/UD 6 9 N.C. N.C. 7 8 N.C. N.C. 7 8 N.C. TSSOP TSSOP *SEE FUNCTIONAL DIAGRAM ______________________________________________________________________________________ 19 MAX5481–MAX5484 Selector Guide 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.) (NE - 1) X e E MARKING 12x16L QFN THIN.EPS MAX5481–MAX5484 10-Bit, Nonvolatile, Linear-Taper Digital Potentiometers E/2 D2/2 (ND - 1) X e AAAA D/2 e CL D D2 k CL b 0.10 M C A B E2/2 L E2 0.10 C C L 0.08 C C L A A2 A1 L L e e PACKAGE OUTLINE 8, 12, 16L THIN QFN, 3x3x0.8mm 21-0136 PKG 8L 3x3 REF. 12L 3x3 16L 3x3 MIN. NOM. MAX. MIN. NOM. MAX. 0.70 0.75 0.80 0.70 0.75 0.80 0.70 0.75 0.80 b 0.25 0.30 0.35 0.20 0.25 0.30 0.20 0.25 0.30 D 2.90 3.00 3.10 2.90 3.00 3.10 2.90 3.00 3.10 E 2.90 3.00 3.10 2.90 3.00 3.10 2.90 3.00 3.10 L 0.35 0.55 0.50 BSC. 0.50 BSC. 0.65 BSC. 0.75 0.45 0.55 0.65 0.30 0.40 N 8 12 16 ND 2 3 4 2 NE 0 A1 A2 k 0.02 3 0.05 0 0.20 REF 0.25 - 0.02 - 0.25 - 0.50 4 0.05 0 0.20 REF 0.02 0.05 0.20 REF - 0.25 - 1 2 EXPOSED PAD VARIATIONS MIN. NOM. MAX. A e I PKG. CODES TQ833-1 E2 D2 PIN ID JEDEC MIN. NOM. MAX. MIN. NOM. MAX. 0.25 0.70 1.25 0.25 0.70 1.25 0.35 x 45° WEEC WEED-1 T1233-1 0.95 1.10 1.25 0.95 1.10 1.25 0.35 x 45° T1233-3 0.95 1.10 1.25 0.95 1.10 1.25 0.35 x 45° WEED-1 T1233-4 0.95 1.10 1.25 0.95 1.10 1.25 0.35 x 45° WEED-1 T1633-2 0.95 1.10 1.25 0.95 1.10 1.25 0.35 x 45° WEED-2 T1633F-3 0.65 0.80 0.95 0.65 0.80 0.95 0.225 x 45° WEED-2 T1633FH-3 0.65 0.80 0.95 0.65 0.80 0.95 0.225 x 45° WEED-2 T1633-4 0.95 1.10 1.25 0.95 1.10 1.25 0.35 x 45° WEED-2 T1633-5 0.95 1.10 1.25 0.95 1.10 1.25 0.35 x 45° WEED-2 - NOTES: 1. 2. 3. 4. 5. 6. 7. 8. 9. 10. 11. 12. DIMENSIONING & TOLERANCING CONFORM TO ASME Y14.5M-1994. ALL DIMENSIONS ARE IN MILLIMETERS. ANGLES ARE IN DEGREES. N IS THE TOTAL NUMBER OF TERMINALS. 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. DIMENSION b APPLIES TO METALLIZED TERMINAL AND IS MEASURED BETWEEN 0.20 mm AND 0.25 mm FROM TERMINAL TIP. ND AND NE REFER TO THE NUMBER OF TERMINALS ON EACH D AND E SIDE RESPECTIVELY. DEPOPULATION IS POSSIBLE IN A SYMMETRICAL FASHION. COPLANARITY APPLIES TO THE EXPOSED HEAT SINK SLUG AS WELL AS THE TERMINALS. DRAWING CONFORMS TO JEDEC MO220 REVISION C. MARKING IS FOR PACKAGE ORIENTATION REFERENCE ONLY. NUMBER OF LEADS SHOWN ARE FOR REFERENCE ONLY. WARPAGE NOT TO EXCEED 0.10mm. PACKAGE OUTLINE 8, 12, 16L THIN QFN, 3x3x0.8mm 21-0136 20 I 2 2 ______________________________________________________________________________________ 10-Bit, Nonvolatile, Linear-Taper Digital Potentiometers TSSOP4.40mm.EPS PACKAGE OUTLINE, TSSOP 4.40mm BODY 21-0066 I 1 1 Revision History Pages changed at Rev 3: 1, 11, 19, 20, 21 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. Maxim Integrated Products, 120 San Gabriel Drive, Sunnyvale, CA 94086 408-737-7600 ____________________ 21 © 2007 Maxim Integrated Products is a registered trademark of Maxim Integrated Products, Inc. MAX5481–MAX5484 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.)