19-3511; Rev 1; 12/04 32-Tap, Nonvolatile, I2C, Linear, Digital Potentiometers The MAX5432–MAX5435 nonvolatile, linear-taper, digital potentiometers perform the function of a mechanical potentiometer, but replace the mechanics with a simple 2-wire serial interface. Each device performs the same function as a discrete potentiometer or a variable resistor and has 32 tap points. The MAX5432–MAX5435 feature an internal, nonvolatile, electrically erasable programmable read-only memory (EEPROM) that returns the wiper to its previously stored position at power-up. The fast-mode I2C†-compatible serial interface allows communication at data rates up to 400kbps, minimizing board space and reducing interconnection complexity. Each device is available with one of four factory-preset I 2 C addresses (see the Selector Guide). Use the MAX5432–MAX5435 in applications requiring digitally controlled resistors. Two resistance values are available (50kΩ and 100kΩ) in a voltage-divider or variable resistor configuration. The nominal resistor temperature coefficient is 35ppm/°C end-to-end, and only 5ppm/°C ratiometric, making the devices ideal for applications requiring a low-temperature-coefficient variable resistor such as low-drift, programmable-gain amplifier circuit configurations. Features ♦ Tiny 3mm x 3mm 8-Pin TDFN and 6-Pin Thin SOT23 Packages ♦ Power-On Recall of Wiper Position from Nonvolatile Memory ♦ 35ppm/°C End-to-End Resistance Temperature Coefficient ♦ 5ppm/°C Ratiometric Temperature Coefficient ♦ 50kΩ/100kΩ Resistor Values ♦ Fast 400kbps I2C-Compatible Serial Interface ♦ 500nA (typ) Static Supply Current ♦ +2.7V to +5.25V Single-Supply Operation ♦ 32 Tap Positions ♦ ±0.15 LSB INL (typ), ±0.15 LSB DNL (typ) Ordering Information PART TEMP RANGE PIN-PACKAGE -40°C to +85°C 8 TDFN-EP** MAX5432META* -40°C to +85°C 8 TDFN-EP** MAX5433LETA -40°C to +85°C 8 TDFN-EP** MAX5433META* -40°C to +85°C 8 TDFN-EP** The MAX5432/MAX5433 are available in a 3mm x 3mm 8pin TDFN package and the MAX5434/MAX5435 are available in a 6-pin thin SOT23 package. The MAX5432– MAX5435 are specified over the extended (-40°C to +85°C) temperature range. MAX5434LEZT-T -40°C to +85°C 6 Thin SOT23-6 MAX5434MEZT-T* -40°C to +85°C 6 Thin SOT23-6 MAX5434NEZT-T* -40°C to +85°C 6 Thin SOT23-6 MAX5434PEZT-T* -40°C to +85°C 6 Thin SOT23-6 Applications MAX5435LEZT-T -40°C to +85°C 6 Thin SOT23-6 MAX5435MEZT-T* -40°C to +85°C 6 Thin SOT23-6 MAX5432LETA Mechanical Potentiometer Replacement MAX5435NEZT-T* -40°C to +85°C 6 Thin SOT23-6 Low-Drift Programmable-Gain Amplifiers MAX5435PEZT-T* -40°C to +85°C 6 Thin SOT23-6 Volume Control Liquid-Crystal Display (LCD) Screen Adjustment *Future product—contact factory for availability. **EP = Exposed pad. Pin Configurations Selector Guide appears at end of data sheet. of I2C components from Maxim Integrated Products, Inc., or one of its sublicensed Associated Companies, conveys a license under the Philips I2C Patent Rights to use these components in an I2C system, provided that the system conforms to the I2C Standard Specification as defined by Philips. †Purchase TOP VIEW H 1 8 W VDD 1 6 L SDA 2 7 L GND 2 5 W 4 SDA GND 3 SCL 4 6 A0 MAX5432 MAX5433 5 VDD SCL 3 MAX5434 MAX5435 SOT23 TDFN ________________________________________________________________ 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 MAX5432–MAX5435 General Description MAX5432–MAX5435 32-Tap, Nonvolatile, I2C, Linear, Digital Potentiometers ABSOLUTE MAXIMUM RATINGS VDD to GND ...........................................................-0.3V to +6.0V SDA, SCL to GND..................................................-0.3V to +6.0V A0, H, L, and W to GND .............................-0.3V to (VDD + 0.3V) Maximum Continuous Current into H, L, and W MAX5432/MAX5434.....................................................±1.3mA MAX5433/MAX5435.....................................................±0.6mA Input/Output Latchup Immunity........................................±50mA Continuous Power Dissipation (TA = +70°C) 6-Pin Thin SOT23 (derate 9.1mW/°C above +70°C) ....727mW 8-Pin TDFN (derate 18.2mW/°C above +70°C) ......1454.5mW 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, VH = VDD, VL = GND, TA = -40°C to +85°C, unless otherwise noted. Typical values are at VDD = +5V, TA = +25°C.) (Note 1) PARAMETER SYMBOL CONDITIONS MIN TYP MAX UNITS DC PERFORMANCE Resolution 32 End-to-End Resistance RH-L End-to-End Resistance Temperature Coefficient TCR 37.5 50 62.5 MAX5433/MAX5435 75 100 125 Ratiometric Resistance Temperature Coefficient Variable resistor (Note 2) Integral Nonlinearity INL Voltage-divider, MAX5432/MAX5433 (Note 3) Variable resistor (Note 2) Differential Nonlinearity DNL Voltage-divider, MAX5432/MAX5433 (Note 3) Full-Scale Error (Note 4) Zero-Scale Error (Note 5) Wiper Resistance Taps MAX5432/MAX5434 35 ppm/°C 5 ppm/°C VDD = 5V ±0.15 ±0.5 VDD = 3V ±0.15 ±0.5 VDD = 5V ±0.15 ±0.5 VDD = 3V ±0.15 ±0.5 VDD = 5V ±0.15 ±0.5 VDD = 3V ±0.15 ±0.5 VDD = 5V ±0.15 ±0.5 VDD = 3V ±0.15 ±0.5 MAX5432, 50kΩ -0.5 MAX5433, 100kΩ -0.5 MAX5432, 50kΩ +0.5 MAX5433, 100kΩ +0.5 RW MAX5432/MAX5433 (Note 6) Input High Voltage VIH (Note 7) Input Low Voltage VIL (Note 7) kΩ 610 1200 LSB LSB LSB LSB Ω DIGITAL INPUTS Input Leakage Current Input Capacitance 2 0.7 x VDD V 0.3 x VDD ILEAK ±1 5 _______________________________________________________________________________________ V µA pF 32-Tap, Nonvolatile, I2C, Linear, Digital Potentiometers (VDD = +2.7V to +5.25V, VH = VDD, VL = GND, TA = -40°C to +85°C, unless otherwise noted. Typical values are at VDD = +5V, TA = +25°C.) (Note 1) PARAMETER SYMBOL CONDITIONS MIN TYP MAX UNITS DYNAMIC CHARACTERISTICS -3dB Bandwidth (Note 8) Wiper Settling Time (Note 9) MAX5432/MAX5434 500 MAX5433/MAX5435 250 MAX5432/MAX5434 0.5 MAX5433/MAX5435 1.0 kHz µs NONVOLATILE MEMORY RELIABILITY Data Retention Endurance TA = +85°C 50 TA = +25°C 200,000 TA = +85°C 50,000 Years Stores POWER SUPPLY Power-Supply Voltage VDD Standby Current IDD Programming Current 5.25 V Digital inputs = VDD or GND, TA = +25°C 2.70 0.5 2 µA During nonvolatile write; digital inputs = VDD or GND (Note 10) 200 900 µA TIMING CHARACTERISTICS (VDD = +2.7V to +5.25V, VH = VDD, VL = GND, TA = -40°C to +85°C, unless otherwise noted. Typical values are at VDD = +5V, TA = +25°C.) (Figures 1 and 2) (Note 11) PARAMETER SCL Clock Frequency SYMBOL CONDITIONS MIN TYP fSCL MAX UNITS 400 kHz Setup Time for START Condition tSU-STA 0.6 µs Hold Time for START Condition tHD-STA 0.6 µs CLK High Time tHIGH 0.6 µs CLK Low Time tLOW 1.3 µs Data Setup Time tSU-DAT 100 Data Hold Time tHD-DAT 0 SDA, SCL Rise Time SDA, SCL Fall Time ns tR tF 0.9 µs 300 ns 300 ns Setup Time for STOP Condition tSU-STO 0.6 µs Bus Free Time Between STOP and START Condition tBUF 1.3 µs Pulse Width of Spike Suppressed tSP Capacitive Load for Each Bus Line CB Nonvolatile Store Time (Note 12) Idle time required after a nonvolatile memory write (Note 13) 50 ns 400 pF 12 ms Note 1: All devices are production tested at TA = +25°C and are guaranteed by design and characterization for -40°C < TA < +85°C. _______________________________________________________________________________________ 3 MAX5432–MAX5435 ELECTRICAL CHARACTERISTICS (continued) TIMING CHARACTERISTICS (continued) (VDD = +2.7V to +5.25V, VH = VDD, VL = GND, TA = -40°C to +85°C, unless otherwise noted. Typical values are at VDD = +5V, TA = +25°C.) (Figures 1 and 2) (Note 1) Note 2: The DNL and INL are measured with the potentiometer configured as a variable resistor. For the 3-terminal potentiometers (MAX5432/MAX5433), H is unconnected and L = GND. At VDD = 5V, W is driven with a source current of 80µA for the 50kΩ configuration, and 40µA for the 100kΩ configuration. At VDD = 3V, W is driven with a source current of 40µA for the 50kΩ configuration, and 20µA for the 100kΩ configuration. Note 3: The DNL and INL are measured with the potentiometer configured as a voltage-divider with H = VDD and L = GND (MAX5432/MAX5433 only). The wiper terminal is unloaded and measured with an ideal voltmeter. Note 4: Full-scale error is defined as VW - VH . ⎛ VH ⎞ ⎜ ⎟ ⎝ 31 ⎠ Note 5: Zero-scale error is defined as VW - VL . ⎛ VH ⎞ ⎜ ⎟ ⎝ 31 ⎠ Note 6: The wiper resistance is the worst value measured by injecting the currents given in Note 2 into W with L = GND. RW = (VW - VH) / IW. Note 7: The device draws current in excess of the specified 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 8: Wiper is at midscale with a 10pF capacitive load. Potentiometer set to midscale, L = GND, an AC source is applied to H, and the output is measured as 3dB lower than the DC W/H value in dB. Note 9: This is measured from the STOP pulse to the time it takes the output to reach 50% of the output step size (divider mode). It is measured with a maximum external capacitive load of 10pF. Note 10: The programming current exists only during NV writes (12ms typ). Note 11: Digital timing is guaranteed by design and characterization, and is not production tested. Note 12: An appropriate bus pullup resistance must be selected depending on board capacitance. Refer to the I2C-bus specification document linked to this web address: www.semiconductors.philips.com/acrobat/literature/9398/39340011.pdf Note 13: The idle time begins from the initiation of the stop pulse. Typical Operating Characteristics (VDD = +5V, TA = +25°C, unless otherwise noted.) 0.6 VDD = 3V 0.3 0.6 0.4 0.2 0 -15 10 35 TEMPERATURE (°C) 60 85 VDD = 5V 100 10 VDD = 3V 1 0.1 0 -40 4 0.8 1000 SUPPLY CURRENT (µA) VDD = 5V MAX5432–35 toc02 1.2 DIGITAL INPUTS = GND OR VDD SUPPLY CURRENT (µA) DIGITAL INPUTS = GND OR VDD 0.9 1.0 MAX5432–35 toc01 1.5 SUPPLY CURRENT vs. DIGITAL INPUT VOLTAGE SUPPLY CURRENT vs. SUPPLY VOLTAGE MAX5432–35 toc03 STANDBY SUPPLY CURRENT vs. TEMPERATURE SUPPLY CURRENT (µA) MAX5432–MAX5435 32-Tap, Nonvolatile, I2C, Linear, Digital Potentiometers 2.5 3.0 3.5 4.0 4.5 SUPPLY VOLTAGE (V) 5.0 5.5 0 1 2 3 DIGITAL INPUT VOLTAGE (V) _______________________________________________________________________________________ 4 5 32-Tap, Nonvolatile, I2C, Linear, Digital Potentiometers END-TO-END RESISTANCE % CHANGE vs. TEMPERATURE 0.5 0 -0.5 MAX5432–35 toc06 1.0 MAX5432-35 toc05 50kΩ 100kΩ END-TO-END RESISTANCE % CHANGE MAX5432–35 toc04 1.0 END-TO-END RESISTANCE CHANGE ( %) TAP-TO-TAP SWITCHING TRANSIENT (0 TO MIDSCALE, CL = 10pF) END-TO-END RESISTANCE % CHANGE vs. TEMPERATURE 0.5 SDA 2V/div 0 VW 1V/div -0.5 50kΩ -1.0 -40 -15 10 35 60 -1.0 85 -40 -15 10 35 60 TEMPERATURE (°C) TEMPERATURE (°C) TAP-TO-TAP SWITCHING TRANSIENT (0 TO MIDSCALE, CL = 10pF) WIPER TRANSIENT AT POWER-ON 1µs/div 85 MIDSCALE WIPER TRANSIENT AT POWER-ON MAX5432–35 toc08 MAX5432–35 toc07 MAX5432–35 toc09 VDD 2V/div SDA 2V/div VDD 2V/div VW 1V/div VW 1V/div 50kΩ 100kΩ 1µs/div 10µs/div MIDSCALE WIPER RESPONSE vs. FREQUENCY (MAX5432) MIDSCALE WIPER RESPONSE vs. FREQUENCY (MAX5433) GAIN (dB) GAIN (dB) -9 CW = 33pF -9 CW = 33pF -12 -12 -15 -15 VDD = 3V 600 RESISTANCE (Ω) -6 -6 700 MAX5432–35 toc12 CW = 10pF CW = 10pF -3 WIPER RESISTANCE vs. TAP POSITION (MAX5432) MAX5432–35 toc11 -3 100kΩ 10µs/div 0 MAX5432 toc10 0 VW 1V/div 500 400 300 200 100 -18 -18 0.1 1 10 FREQUENCY (kHz) 100 1000 0 0.1 1 10 FREQUENCY (kHz) 100 1000 0 4 8 12 16 20 24 28 31 TAP POSITION _______________________________________________________________________________________ 5 MAX5432–MAX5435 Typical Operating Characteristics (continued) (VDD = +5V, TA = +25°C, unless otherwise noted.) Typical Operating Characteristics (continued) (VDD = +5V, TA = +25°C, unless otherwise noted.) WIPER RESISTANCE vs. TAP POSITION (MAX5432) 400 300 300 500 400 300 200 200 200 100 100 100 0 0 8 12 16 20 24 0 28 31 4 8 16 20 24 28 0 31 0 30 0.5 VARIABLE-RESISTOR MODE MAX5432/MAX5434 0.4 0.3 RESISTANCE DNL (LSB) MAX5432–35 toc16 100kΩ 60 50 40 0.2 0.1 0 -0.1 -0.2 0.1 0 -0.1 -0.2 -0.4 -0.5 20 TAP POSITION 24 28 31 28 31 0.2 0 16 24 0.3 10 12 20 VARIABLE-RESISTOR MODE MAX5432/MAX5434 0.4 -0.3 8 16 RESISTANCE INL vs. TAP POSITION -0.4 4 12 0.5 -0.3 50kΩ 0 8 TAP POSITION RESISTANCE DNL vs. TAP POSITION W-TO-L RESISTANCE vs. TAP POSITION 120 110 100 20 4 TAP POSITION TAP POSITION 90 80 70 12 RESISTANCE INL (LSB) 4 MAX5432–35 toc17 0 6 VDD = 5V 600 500 400 MAX5432-35 toc15 600 RESISTANCE (Ω) 500 VDD = 5V RESISTANCE (Ω) 600 700 MAX5432–35 toc14 VDD = 3V RESISTANCE (Ω) 700 MAX5432-35 toc13 700 WIPER RESISTANCE vs. TAP POSITION (MAX5433) MAX5432–35 toc18 WIPER RESISTANCE vs. TAP POSITION (MAX5433) W-TO-L RESISTANCE (kΩ) MAX5432–MAX5435 32-Tap, Nonvolatile, I2C, Linear, Digital Potentiometers -0.5 0 4 8 12 16 20 TAP POSITION 24 28 31 0 4 8 12 16 20 TAP POSITION _______________________________________________________________________________________ 24 28 31 32-Tap, Nonvolatile, I2C, Linear, Digital Potentiometers 0.1 0 -0.1 -0.2 0.2 0.1 0 -0.1 -0.2 0.2 0.1 0 -0.1 -0.2 -0.3 -0.3 -0.4 -0.4 -0.4 -0.5 -0.5 8 12 16 20 24 28 31 -0.5 0 4 8 16 20 24 28 31 0 RESISTANCE INL vs. TAP POSITION 0.1 0 -0.1 -0.2 VOLTAGE-DIVIDER MODE MAX5433 0.4 0.3 0.2 0.1 0 -0.1 -0.2 0.1 0 -0.1 -0.2 -0.3 -0.4 -0.5 -0.5 TAP POSITION 24 28 31 28 31 0.2 -0.4 20 24 0.3 -0.4 16 20 VOLTAGE-DIVIDER MODE MAX5433 0.4 -0.3 12 16 RESISTANCE INL vs. TAP POSITION -0.3 8 12 0.5 RESISTANCE INL (LSB) 0.2 0.5 RESISTANCE DNL (LSB) 0.3 4 8 TAP POSITION RESISTANCE DNL vs. TAP POSITION MAX5432-35 toc22 VARIABLE-RESISTOR MODE MAX5433/MAX5435 0 4 TAP POSITION 0.5 0.4 12 MAX5432-35 toc23 4 TAP POSITION RESISTANCE INL (LSB) 0.3 -0.3 0 VARIABLE-RESISTOR MODE MAX5433/MAX5435 0.4 MAX5432-35 toc24 0.2 0.5 MAX5432-35 toc21 0.3 RESISTANCE INL (LSB) RESISTANCE DNL (LSB) 0.3 VOLTAGE-DIVIDER MODE MAX5432 0.4 RESISTANCE DNL vs. TAP POSITION MAX5432–35 toc20 MAX5432–35 toc19 VOLTAGE-DIVIDER MODE MAX5432 0.4 RESISTANCE INL vs. TAP POSITION 0.5 RESISTANCE DNL (LSB) RESISTANCE DNL vs. TAP POSITION 0.5 -0.5 0 4 8 12 16 20 TAP POSITION 24 28 31 0 4 8 12 16 20 24 28 31 TAP POSITION _______________________________________________________________________________________ 7 MAX5432–MAX5435 Typical Operating Characteristics (continued) (VDD = +5V, TA = +25°C, unless otherwise noted.) Pin Description PIN NAME FUNCTION TDFN THIN SOT23 1 — H 2 4 SDA I2C-Compatible Interface Data Input 3 2 GND Ground 4 3 SCL I2C-Compatible Interface Clock Input 5 1 VDD 6 — A0 7 6 L 8 5 W Wiper Terminal EP — EP Exposed Pad. Internally connected to GND. High Terminal Power-Supply Input. Bypass with a 0.1µF capacitor from VDD to GND. Address Input. Sets the I2C address. Connect to VDD or GND. Do not leave A0 floating. Low Terminal Detailed Description The MAX5432–MAX5435 contain a resistor array with 31 resistive elements. The MAX5432/MAX5434 provide a total end-to-end resistance of 50kΩ, and the MAX5433/MAX5435 provide an end-to-end resistance of 100kΩ. The MAX5432/MAX5433 allow access to the high, low, and wiper terminals for a standard voltage-divider configuration. Connect H, L, and W in any desired configuration as long as their voltages fall between GND and V DD. The MAX5434/MAX5435 are variable resistors with H internally connected to the wiper. A simple 2-wire I2C-compatible serial interface moves the wiper among the 32 tap points. Eight data bits, an address byte, and a control byte program the wiper position. A nonvolatile memory stores and recalls the wiper position in the nonvolatile memory upon power-up. The nonvolatile memory is guaranteed for 200,000 wiper store cycles and 50 years for wiper data retention. Digital Interface The MAX5432–MAX5435 feature an internal, nonvolatile EEPROM that returns the wiper to its previously stored position at power-up. The shift register decodes the control and address bits, routing the data to the proper memory registers. Write data to the volatile memory register to immediately update the wiper position, or write data to the nonvolatile register for storage. Writing to the nonvolatile register takes a minimum of 12ms. The volatile register retains data as long as the device is enabled and powered. Removing power clears the volatile register. The nonvolatile register retains data even after power is removed. Upon power-up, the 8 power-on reset circuitry and internal oscillator control the transfer of data from the nonvolatile register to the volatile register. Serial Addressing The MAX5432–MAX5435 operate as a slave that sends and receives data through an I2C- and SMBus™-compatible 2-wire interface. The interface uses a serial data access (SDA) line and a serial clock line (SCL) to achieve bidirectional communication between master(s) and slave(s). A master, typically a microcontroller, initiates all data transfers to and from the MAX5432–MAX5435, and generates the SCL clock that synchronizes the data transfer (Figure 1). SDA operates as both an input and an open-drain output. SDA requires a pullup resistor, typically 4.7kΩ. SCL only operates as an input. SCL requires a pullup resistor (4.7kΩ typ) if there are multiple masters on the 2-wire interface, or if the master in a single-master system has an open-drain SCL output. Each transmission consists of a START (S) condition (Figure 3) sent by a master, followed by the MAX5432–MAX5435 7-bit slave address plus the 8th bit (Figure 4), 1 command byte (Figure 7) and 1 data byte, and finally a STOP (P) condition (Figure 3). Start and Stop Conditions Both SCL and SDA remain high when the interface is not busy. A master signals the beginning of a transmission with a START (S) condition by transitioning SDA from high to low while SCL is high. When the master has finished communicating with the slave, it issues a STOP (P) condition by transitioning the SDA from low to SMBus is a trademark of Intel Corporation. _______________________________________________________________________ MAX5432–MAX5435 MAX5432–MAX5435 32-Tap, Nonvolatile, I2C, Linear, Digital Potentiometers 32-Tap, Nonvolatile, I2C, Linear, Digital Potentiometers tF SDA tSU-DAT tHD-DAT tLOW tBUF tHD-STA tSU-STA tSU-STO SCL tHIGH tHD-STA tR tF S Sr A P S PARAMETERS ARE MEASURED FROM 30% TO 70%. Figure 1. I2C Serial-Interface Timing Diagram high while SCL is high. The bus is then free for another transmission (Figure 3). Bit Transfer One data bit is transferred during each clock pulse. The data on the SDA line must remain stable while SCL is high (Figure 5). Acknowledge The acknowledge bit is a clocked 9th bit that the recipient uses to handshake receipt of each byte of data (Figure 6). Each byte transferred effectively requires 9 bits. The master generates the 9th clock pulse, and the recipient pulls down SDA during the acknowledge clock pulse, so the SDA line is stable low during the high period of the clock pulse. When the master transmits to the MAX5432–MAX5435, the devices generate the acknowledge bit because the MAX5432–MAX5435 are the recipients. Slave Address The MAX5432–MAX5435 have a 7-bit-long slave address (Figure 4). The 8th bit following the 7-bit slave address is the NOP/W bit. Set the NOP/W bit low for a write command and high for a no-operation command. Table 1a shows four possible slave addresses for the MAX5432/MAX5433 and Table 1b shows four possible slave addresses for the MAX5434/MAX5435. The first 4 bits (MSBs) of the slave addresses are always 0101. Bits A2 and A1 are factory programmed for the MAX5432/MAX5433 (Table 1a). Connect the A0 input (MAX5432/MAX5433 only) to either GND or V DD to select one of two I2C device addresses. Each device must have a unique address to share the bus. A maximum of four MAX5432/MAX5433 devices can share the same bus. Bits A2, A1, and A0 are factory programmed for the MAX5434/MAX5435 (Table 1b). Table 1a. Address Codes (MAX5432/MAX5433 Only) ADDRESS BYTE PART SUFFIX A6 A5 A4 A3 A2 A1 A0 NOP/W L 0 1 0 1 0 0 0 NOP/W L 0 1 0 1 0 0 1 NOP/W M 0 1 0 1 1 0 0 NOP/W M 0 1 0 1 1 0 1 NOP/W A0 NOP/W Table 1b. Address Codes (MAX5434/MAX5435 Only) ADDRESS BYTE PART SUFFIX A6 A5 A4 A3 A2 A1 L 0 1 0 1 0 0 0 NOP/W M 0 1 0 1 1 0 0 NOP/W N 0 1 0 1 0 1 0 NOP/W P 0 1 0 1 1 1 0 NOP/W Message Format for Writing A write to the MAX5432–MAX5435 consists of the transmission of the device’s slave address with the 8th bit set to zero, followed by at least 1 byte of information. The 1st byte of information is the command byte. The bytes received after the command byte are the data bytes. The 1st data byte goes into the internal register of the MAX5432–MAX5435 as selected by the command byte (Figure 8). __________________________________________________________________________ MAX5432–MAX5435 tR VDD IOL = 3mA SDA VOUT SDA SCL 400pF IOH = 0mA Figure 2. Load Circuit SDA S P START CONDITION STOP CONDITION Figure 3. Start and Stop Conditions 0 1 0 1 0* 0* A0 MSB NOP/W ACK LSB SCL *SEE THE Selector Guide FOR OTHER ADDRESS OPTIONS. Figure 4. Slave Address Command Byte Use the command byte to select the destination of the wiper data (nonvolatile or volatile memory registers) and swap data between nonvolatile and volatile memory registers (see Table 2). Command Descriptions VREG: The data byte writes to the volatile memory register and the wiper position updates with the data in the volatile memory register. NVREG: The data byte writes to the nonvolatile memory register. The wiper position is unchanged. Data Byte The MAX5432–MAX5435 use the first 5 bits (MSBs, D7–D3) of the data byte to set the position of the wiper. The last 3 bits (D2, D1, and D0) are don’t care bits (see Table 2). NVREGxVREG: Data transfers from the nonvolatile memory register to the volatile memory register (wiper position updates). VREGxNVREG: Data transfers from the volatile memory register into the nonvolatile memory register. Table 2. Command Byte Summary ADDRESS BYTE START 1 2 3 4 5 6 COMMAND BTYE 7 8 DATA BYTE 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 A C K A C7 C6 C5 C4 C3 C2 C1 C0 C K D7 D6 D5 D4 D3 D2 D1 D0 VREG 0 1 0 1 A2 A1 A0 N O P/ W 0 0 0 0 1 0 0 0 1 D7 D6 D5 D4 D3 X X X NVREG 0 1 0 1 A2 A1 A0 0 0 0 1 0 0 0 0 1 D7 D6 D5 D4 D3 X X X NVREGxVREG 0 1 0 1 A2 A1 A0 0 0 1 1 0 0 0 0 1 D7 D6 D5 D4 D3 X X X VREGxNVREG 0 1 0 1 A2 A1 A0 0 0 1 0 1 0 0 0 1 D7 D6 D5 D4 D3 X X X SCL CYCLE NUMBER A6 A5 A4 A3 A2 A1 A0 X = Don’t care. 10 ______________________________________________________________________ A C K STOP REGISTER MAX5432–MAX5435 MAX5432–MAX5435 32-Tap, Nonvolatile, I2C, Linear, Digital Potentiometers 32-Tap, Nonvolatile, I2C, Linear, Digital Potentiometers SDA MAX5432–MAX5435 CLOCK PULSE FOR ACKNOWLEDGMENT START CONDITION SCL 1 2 8 9 NOT ACKNOWLEDGE SCL DATA STABLE, DATA VALID SDA CHANGE OF DATA ALLOWED ACKNOWLEDGE Figure 6. Acknowledge Figure 5. Bit Transfer COMMAND BYTE IS STORED ON RECEIPT OF STOP CONDITION SLAVE ADDRESS S D15 ACKNOWLEDGE FROM MAX5432–MAX5435 0 D14 D13 A D11 D12 D10 D9 D8 A COMMAND BYTE P ACKNOWLEDGE FROM MAX5432–MAX5435 NOP/W Figure 7. Command Byte Received ACKNOWLEDGE FROM MAX5432–MAX5435 ACKNOWLEDGE FROM MAX5432–MAX5435 HOW COMMAND BYTE AND DATA BYTE MAP INTO MAX5432–MAX5435's REGISTERS ACKNOWLEDGE FROM MAX5432–MAX5435 S D15 D14 D13 D12 D11 D10 0 SLAVE ADDRESS A COMMAND BYTE D9 D8 D7 A D6 D5 D4 D3 DATA BYTE X X X A P 1 BYTE NOP/W Figure 8. Command and Single Data Byte Received Nonvolatile Memory The internal EEPROM consists of a 5-bit nonvolatile register that retains the value written to it before the device is powered down. The nonvolatile register is programmed with the zeros at the factory. Wait a minimum of 12ms after writing to NVREG before sending another command. with the data stored in the nonvolatile memory register. This initialization period takes 20µs. Standby The MAX5432–MAX5435 feature a low-power standby mode. When the device is not being programmed, it goes into standby mode and current consumption is typically 0.5µA. Power-Up Upon power-up, the MAX5432–MAX5435 load the data stored in the nonvolatile memory register into the volatile memory register, updating the wiper position ______________________________________________________________________________________ 11 5V 5V H 30V 30V W MAX5432 MAX5433 VOUT VOUT H L MAX5432– MAX5435 W L Figure 9. Positive LCD Bias Control Using a Voltage-Divider W VIN Figure 10. Positive LCD Bias Control Using a Variable Resistor +5V L H R3 VIN C VOUT V0 REF OUT H R1 R1 MAX6160 ADJ GND W H MAX5432– MAX5435 R2 W L MAX5432 MAX5433 R2 L V0 = 1.23V 50kΩ FOR THE MAX5432 R2(kΩ) V0 = 1.23V 100kΩ FOR THE MAX5433 R2(kΩ) Figure 12. Adjustable Voltage Reference Figure 11. Programmable Filter Applications Information Use the MAX5432–MAX5435 in applications requiring digitally controlled adjustable resistance, such as LCD contrast control (where voltage biasing adjusts the display contrast), or for programmable filters with adjustable gain and/or cutoff frequency. Positive LCD Bias Control Figures 9 and 10 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 made by the potentiometer (Figure 9) or to a fixed resistor and a variable resistor (Figure 10). R2, and the cutoff frequency is adjusted by R3. Use the following equations to calculate the gain (G) and the 3dB cutoff frequency (fC). R1 R2 1 fC = 2π × R 3 × C G = 1+ Adjustable Voltage Reference Figure 12 shows the MAX5432/MAX5433 used as the feedback resistors in an adjustable voltage reference application. Independently adjust the output voltages of the MAX6160 from 1.23V to (VIN - 0.2V) by changing the wiper position of the MAX5432/MAX5433. Programmable Filter Figure 11 shows the configuration for a 1st-order programmable filter. The gain of the filter is adjusted by 12 ______________________________________________________________________________________ MAX5432–MAX5435 MAX5432–MAX5435 32-Tap, Nonvolatile, I2C, Linear, Digital Potentiometers 32-Tap, Nonvolatile, I2C, Linear, Digital Potentiometers H VDD GND SDA SCL 5-BIT SHIFT REGISTER 5-BIT LATCH 5 5 32POSITION DECODER 32 W L POR I2C INTERFACE 5-BIT NV MEMORY MAX5432 MAX5433 A0 MAX5434/MAX5435 Functional Diagram VDD GND SDA SCL 5-BIT SHIFT REGISTER I2C INTERFACE 5-BIT LATCH 5 5 32POSITION DECODER 32 W L POR 5-BIT NV MEMORY MAX5434 MAX5435 ______________________________________________________________________________________ 13 MAX5432–MAX5435 MAX5432/MAX5433 Functional Diagram Selector Guide PART TOP MARK I2C ADDRESS R (kΩ) MAX5432LETA ANG 010100A0 50 MAX5432META ANI 010110A0 50 MAX5433LETA ANF 010100A0 100 MAX5433META ANH 010110A0 100 MAX5434LEZT AABX 0101000 50 MAX5434MEZT AABY 0101100 50 MAX5434NEZT AABS 0101010 50 MAX5434PEZT AABU 0101110 50 MAX5435LEZT AABW 0101000 100 MAX5435MEZT AABV 0101100 100 MAX5435NEZT AABZ 0101010 100 MAX5435PEZT AABT 0101110 100 14 Chip Information TRANSISTOR COUNT: 7817 PROCESS: BiCMOS ______________________________________________________________________________________ MAX5432–MAX5435 MAX5432–MAX5435 32-Tap, Nonvolatile, I2C, Linear, Digital Potentiometers 32-Tap, Nonvolatile, I2C, Linear, Digital Potentiometers 6, 8, &10L, DFN THIN.EPS D N PIN 1 INDEX AREA E E2 DETAIL A C L A C L L L e e PACKAGE OUTLINE, 6,8,10 & 14L, TDFN, EXPOSED PAD, 3x3x0.80 mm -DRAWING NOT TO SCALE- 21-0137 G 1 2 COMMON DIMENSIONS SYMBOL MIN. MAX. A 0.70 0.80 D 2.90 3.10 E 2.90 3.10 A1 0.00 0.05 L 0.20 0.40 k 0.25 MIN. A2 0.20 REF. PACKAGE VARIATIONS PKG. CODE N D2 E2 e JEDEC SPEC b [(N/2)-1] x e DOWNBONDS ALLOWED T633-1 6 1.50±0.10 2.30±0.10 0.95 BSC MO229 / WEEA 0.40±0.05 1.90 REF NO T633-2 6 1.50±0.10 2.30±0.10 0.95 BSC MO229 / WEEA 0.40±0.05 1.90 REF NO T833-1 8 1.50±0.10 2.30±0.10 0.65 BSC MO229 / WEEC 0.30±0.05 1.95 REF NO T833-2 8 1.50±0.10 2.30±0.10 0.65 BSC MO229 / WEEC 0.30±0.05 1.95 REF NO T833-3 8 1.50±0.10 2.30±0.10 0.65 BSC MO229 / WEEC 0.30±0.05 1.95 REF YES T1033-1 10 1.50±0.10 2.30±0.10 0.50 BSC MO229 / WEED-3 0.25±0.05 2.00 REF NO T1433-1 14 1.70±0.10 2.30±0.10 0.40 BSC ---- 0.20±0.05 2.40 REF YES T1433-2 14 1.70±0.10 2.30±0.10 0.40 BSC ---- 0.20±0.05 2.40 REF NO PACKAGE OUTLINE, 6,8,10 & 14L, TDFN, EXPOSED PAD, 3x3x0.80 mm -DRAWING NOT TO SCALE- 21-0137 G 2 2 ______________________________________________________________________________________ 15 MAX5432–MAX5435 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.) 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.) 16 ______________________________________________________________________________________ MAX5432–MAX5435 MAX5432–MAX5435 32-Tap, Nonvolatile, I2C, Linear, Digital Potentiometers 32-Tap, Nonvolatile, I2C, Linear, Digital Potentiometers 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 ____________________ 17 © 2004 Maxim Integrated Products Printed USA is a registered trademark of Maxim Integrated Products. MAX5432–MAX5435 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.)