Dual, 8-Bit, Low-Power, 2-Wire, Serial Voltage-Output DAC

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19-3538; Rev ; 2/5 Dual, 8-Bit, Low-Power, 2-Wire, Serial Voltage-Output General Description The is a dual, 8-bit voltage-output, digital-toanalog converter () with an I 2 C*-compatible, 2-wire interface that operates at clock rates up to 4kHz. The device operates from a single 2.7V to 5.5V supply (115µA at = 3.6V). A power-down mode decreases current consumption to less than 1µA. The features three software-selectable power-down output impedances: 1kΩ, 1kΩ, and high impedance. Other features include internal precision rail-to-rail output buffers and a power-on reset (POR) circuit that powers up the in the 1kΩ power-down mode. The features a double-buffered I 2 C-compatible serial interface that allows multiple devices to share a single bus. All logic inputs are CMOS-logic compatible and buffered with Schmitt triggers, allowing direct interfacing to optocoupled and transformer-isolated interfaces. The minimizes digital noise feedthrough by disconnecting the clock () signal from the rest of the device when an address mismatch is detected. The is specified over the extended (-4 C to +85 C) temperature range and is available in a small 8-pin µmax package. Refer to the MAX5822 data sheet for the 12-bit version and to the MAX5821 data sheet for a 1-bit version. Applications Digital Gain and Offset Adjustments Programmable Voltage and Current Sources Programmable Attenuation VCO/Varactor Diode Control Low-Cost Instrumentation Battery-Operated Instrumentation Pin Configuration Features Ultra-Low Supply Current 115µA at = 3.6V 135µA at = 5.5V 3nA Low-Power Power-Down Mode Single 2.7V to 5.5V Supply Voltage Fast 4kHz I 2 C-Compatible 2-Wire Serial Interface Schmitt-Trigger Inputs for Direct Interfacing to Optocouplers Rail-to-Rail Output Buffer Amplifiers Three Software-Selectable Power-Down Output Impedances 1kΩ, 1kΩ, and High Impedance Readback Mode for Bus and Data Checking Power-On Reset to Zero 8-Pin µmax Package PART µc Ordering Information TEMP RANGE R P R P PIN- PACKAGE ADDRESS LEUA -4 C to +85 C 8 µmax 111 X MEUA -4 C to +85 C 8 µmax 111 X Typical Operating Circuit TOP VIEW 1 8 OUTB R S R S REF OUTA OUTB GND ADD 2 3 4 7 6 5 OUTA REF R S R S OUTA REF OUTB µmax REF µmax is a registered trademark of Maxim Integrated Products, Inc. *Purchase of I 2 C components from Maxim Integrated Products, Inc., or one of its sublicensed Associate Companies, conveys a license under the Philips I 2 C Patent Rights to use these components in an I 2 C system, provided that the system conforms to the I 2 C Standard Specification defined by Philips. Maxim Integrated Products 1 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.

Voltage-Output ABSOLUTE MAXIMUM RATINGS,, to GND...-.3V to +6V, REF, ADD to GND...-.3V to +.3V Maximum Current into Any Pin...5mA Continuous Power Dissipation (T A = +7 C) 8-Pin µmax (derate 4.5mW above +7 C)...362mW Operating Temperature Range...-4 C to +85 C Storage Temperature Range...-65 C to +15 C Maximum Junction Temperature...+15 C Lead Temperature (soldering, 1s)...+3 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 ( = +2.7V to +5.5V, GND =, V REF =, R L = 5kΩ, C L = 2pF, T A = T MIN to T MAX, unless otherwise noted. Typical values are at = +5V, T A = +25 C.) (Note 1) PARAMETER SYMBOL CONDITIONS MIN TYP MAX UNITS STATIC ACCURACY (NOTE 2) Resolution N 8 Bits Integral Nonlinearity INL (Note 3) ±.5 ±1 LSB Differential Nonlinearity DNL Guaranteed monotonic (Note 2) ±.5 LSB Zero-Code Error ZCE Code = hex, = 2.7V 6 4 mv Zero-Code Error Tempco 2.3 ppm/ o C Gain Error GE Code = FF hex -.8-3 %FSR Gain-Error Tempco.26 ppm/ o C Power-Supply Rejection Ratio PSRR Code = FF hex, = 4.5V to 5.5V 58.8 db DC Crosstalk 3 µv REFERENCE INPUT Reference Input Voltage Range V REF V Reference Input Impedance 65 9 kω Reference Current Power-down mode.3 1 µa OUTPUT Output Voltage Range No load (Note 4) V DC Output Impedance Code = 8 hex 1.2 Ω Short-Circuit Current Wake-Up Time Output Leakage Current DIGITAL INPUTS (, ) = 5V, V OUT = full scale (short to GND) 42.2 = 3V, V OUT = full scale (short to GND) 15.1 = 5V 8 = 3V 8 Power-down mode = high impedance, = 5.5V, V OUT _ = to GND Input High Voltage V IH.7 x ma µs ±.1 ±1 µa V Input Low Voltage V IL.3 x V 2

Voltage-Output ELECTRICAL CHARACTERISTICS (continued) ( = +2.7V to +5.5V, GND =, V REF =, R L = 5kΩ, C L = 2pF, T A = T MIN to T MAX, unless otherwise noted. Typical values are at = +5V, T A = +25 C.) (Note 1) PARAMETER SYMBOL CONDITIONS MIN TYP MAX UNITS.5 x Input Hysteresis V Input Leakage Current Digital inputs = or ±.1 ±1 µa Input Capacitance 6 pf DIGITAL OUTPUT () Output Logic-Low Voltage V OL I SINK = 3mA.4 V Tri-State Leakage Current I L Digital inputs = or ±.1 ±1 µa Tri-State Output Capacitance 6 pf DYNAMIC PERFORMANCE Voltage-Output Slew Rate SR.5 V/µs Voltage-Output Settling Time To.5 LSB code 4 hex to C hex or C hex to 4 hex (Note 5) 4 12 µs Digital Feedthrough Code = hex, digital inputs from to.2 nv-s Digital-to-Analog Glitch Impulse Major carry transition (code = 7F hex to 8 hex and 8 hex to 7F hex) 12 nv-s -to- Crosstalk 2.4 nv-s POWER SUPPLIES Supply Voltage Range 2.7 5.5 V All digital inputs at or = 3.6V 115 25 Supply Current with No Load I DD All digital inputs at or = 5.5V 135 215 µa Power-Down Supply Current I DDPD All digital inputs at or = 5.5V.3 1 µa TIMING CHARACTERISTICS (FIGURE 1) Serial Clock Frequency f 4 khz Bus Free Time Between STOP and START Conditions t BUF 1.3 µs START Condition Hold Time t HD, STA.6 µs Pulse-Width Low t LOW 1.3 µs Pulse-Width High t HIGH.6 µs Repeated START Setup Time t SU, STA.6 µs Data Hold Time t HD, DAT.9 µs Data Setup Time t SU, DAT 1 ns and Receiving Rise Time t r (Note 5) 3 ns and Receiving Fall Time t f (Note 5) 3 ns Transmitting Fall Time t f (Note 5) 2 +.1C b 25 ns 3

Voltage-Output ELECTRICAL CHARACTERISTICS (continued) ( = +2.7V to +5.5V, GND =, V REF =, R L = 5kΩ, C L = 2pF, T A = T MIN to T MAX, unless otherwise noted. Typical values are at = +5V, T A = +25 C.) (Note 1) PARAMETER SYMBOL CONDITIONS MIN TYP MAX UNITS STOP Condition Setup Time t SU, STO.6 µs Bus Capacitance C b (Note 5) 4 pf Maximum Duration of Suppressed Pulse Widths t SP 5 ns Note 1: All devices are 1% production tested at T A = +25 C and are guaranteed by design for T A = T MIN to T MAX. Note 2: Static specifications are tested with the output unloaded. Note 3: Linearity is guaranteed from codes 7 to 248. Note 4: Offset and gain error limit the FSR. Note 5: Guaranteed by design. Not production tested. ( = +5V, R L = 5kΩ, T A = +25 C.) Typical Operating Characteristics 1..75.5 INTEGRAL NONLINEARITY vs. INPUT CODE toc1 1.25 1. INTEGRAL NONLINEARITY vs. SUPPLY VOLTAGE toc2 1.25 1. INTEGRAL NONLINEARITY vs. TEMPERATURE toc3 INL (LSB).25 -.25 INL (LSB).75.5 INL (LSB).75.5 -.5 -.75.25.25-1. 64 128 192 256 INPUT CODE 2.7 3.4 4.1 4.8 5.5 SUPPLY VOLTAGE (V) -4-15 1 35 6 85 TEMPERATURE ( C) 1..75.5 DIFFERENTIAL NONLINEARITY vs. INPUT CODE toc4 -.1 DIFFERENTIAL NONLINEARITY vs. SUPPLY VOLTAGE toc5 -.1 DIFFERENTIAL NONLINEARITY vs. TEMPERATURE toc6 DNL (LSB).25 -.25 DNL (LSB) -.2 -.3 DNL (LSB) -.2 -.3 -.5 -.4 -.4 -.75-1. 64 128 192 256 INPUT CODE -.5 2.7 3.4 4.1 4.8 5.5 SUPPLY VOLTAGE (V) -.5-4 -15 1 35 6 85 TEMPERATURE ( C) 4

Voltage-Output ( = +5V, R L = 5kΩ, T A = +25 C.) ZERO-CODE ERROR (mv) 1 8 6 4 2 ZERO-CODE ERROR vs. SUPPLY VOLTAGE toc7 ZERO-CODE ERROR (mv) Typical Operating Characteristics (continued) 1 8 6 4 2 ZERO-CODE ERROR vs. TEMPERATURE toc8 GAIN ERROR (%FSR) -2. -1.6-1.2 -.8 -.4 GAIN ERROR vs. SUPPLY VOLTAGE toc9 2.7 3.4 4.1 4.8 5.5 SUPPLY VOLTAGE (V) -4-15 1 35 6 85 TEMPERATURE ( C) 2.7 3.4 4.1 4.8 5.5 SUPPLY VOLTAGE (V) -2. -1.6 GAIN ERROR vs. TEMPERATURE toc1 6 5 OUTPUT VOLTAGE vs. OUTPUT SOURCE CURRENT (NOTE 6) toc11 2.5 2. OUTPUT VOLTAGE vs. OUTPUT SINK CURRENT (NOTE 6) toc12 GAIN ERROR (%FSR) -1.2 -.8 -.4 OUTPUT VOLTAGE (V) 4 3 2 1 OUTPUT VOLTAGE (V) 1.5 1..5 CODE = 4 hex -4-15 1 35 6 85 TEMPERATURE ( C) CODE = FF hex 2 4 6 8 1 OUTPUT SOURCE CURRENT (ma) 2 4 6 8 1 OUTPUT SINK CURRENT (ma) SUPPLY CURRENT (µa) 18 16 14 12 SUPPLY CURRENT vs. INPUT CODE toc13 SUPPLY CURRENT (µa) 18 16 14 12 SUPPLY CURRENT vs. TEMPERATURE toc14 SUPPLY CURRENT (µa) 18 16 14 12 SUPPLY CURRENT vs. SUPPLY VOLTAGE toc15 1 51 12 153 24 256 INPUT CODE CODE = FF hex 1-4 -15 1 35 6 85 TEMPERATURE ( C) CODE = FF hex 1 2.7 3.4 4.1 4.8 5.5 SUPPLY VOLTAGE (V) 5

Voltage-Output POWER-DOWN SUPPLY CURRENT (na) ( = +5V, R L = 5kΩ, T A = +25 C.) 5 4 3 2 1 POWER-DOWN SUPPLY CURRENT vs. SUPPLY VOLTAGE Z OUT = HIGH IMPEDANCE T A = +25 C T A = -4 C T A = +85 C 2.7 3.4 4.1 4.8 5.5 SUPPLY VOLTAGE (V) toc16 Typical Operating Characteristics (continued) POWER-UP GLITCH 1µs/div toc17 5V 1mV/div EXITING SHUTDOWN 2µs/div toc18 C LOAD = 2pF CODE = 8 hex 5mV/div MAJOR CARRY TRANSITION (POSITIVE) toc19 MAJOR CARRY TRANSITION (NEGATIVE) toc2 SETTLING TIME (POSITIVE) toc21 5mV/div 5mV/div 5mV/div C LOAD = 2pF R L = 5kΩ CODE = 7F hex TO 8 hex 2µs/div C LOAD = 2pF R L = 5kΩ CODE = 8 hex TO 7F hex 2µs/div C LOAD = 2pF CODE = 4 hex TO C hex 2µs/div SETTLING TIME (NEGATIVE) toc22 DIGITAL FEEDTHROUGH toc23 CROSSTALK toc24 2V/div V OUTA 2V/div 5mV/div C LOAD = 2pF CODE = C hex TO 4 hex C LOAD = 2pF f = 12kHz CODE = hex 2mV/div V OUTB 1mV/div 2µs/div 4µs/div 4µs/div Note 6: The ability to drive loads greater than 5kΩ is not implied. 6

Voltage-Output Pin Description PIN NAME FUNCTION 1 Power Supply 2 GND Ground 3 ADD Address Select. A logic-high sets the address LSB to 1; a logic-low sets the address LSB to zero. 4 Serial Clock Input 5 Bidirectional Serial Data Interface 6 REF Reference Input 7 OUTA A Output 8 OUTB B Output Detailed Description The is a dual, 8-bit, voltage-output with an I 2 C/SMBus -compatible 2-wire interface. The device consists of a serial interface, power-down circuitry, dual input and registers, two 8-bit resistor string s, two unity-gain output buffers, and output resistor networks. The serial interface decodes the address and control bits, routing the data to the proper input or register. Data can be directly written to the register, immediately updating the device output, or can be written to the input register without changing the output. Both registers retain data as long as the device is powered. Operation The uses a segmented resistor string architecture, which saves power in the overall system and guarantees output monotonicity. The s input coding is straight binary, with the output voltage given by the following equation: V D V REF OUT _ = N 2 where N = 8 (bits) and D = the decimal value of the input code ( to 255). Output Buffer The analog outputs are buffered by precision, unity-gain followers that slew.5v/µs. Each buffer output swings rail-to-rail, and is capable of driving 5kΩ in parallel with 2pF. The output settles to ±.5 LSB within 4µs. Power-On Reset The features an internal POR circuit that initializes the device upon power-up. The registers are set to zero scale and the device is powered down, with the output buffers disabled and the outputs pulled SMBus is a trademark of Intel Corporation. to GND through the 1kΩ termination resistor. Following power-up, a wake-up command must be initiated before any conversions are performed. Power-Down Modes The has three software-controlled low-power power-down modes. All three modes disable the output buffers and disconnect the resistor strings from REF, reducing supply current draw to 1µA and the reference current draw to less than 1µA. In power-down mode, the device output is high impedance. In power-down mode 1, the device output is internally pulled to GND by a 1kΩ termination resistor. In powerdown mode 2, the device output is internally pulled to GND by a 1kΩ termination resistor. Table 1 shows the power-down mode command words. Upon wake-up, the output is restored to its previous value. Data is retained in the input and registers during power-down mode. Digital Interface The features an I 2 C/SMBus-compatible 2- wire interface consisting of a serial data line () and a serial clock line (). The is SMBus compatible within the range of = 2.7V to 3.6V. and facilitate bidirectional communication between the and the master at rates up to 4kHz. Figure 1 shows the 2-wire interface timing diagram. The is a transmit/receive slave-only device, relying upon a master to generate a clock signal. The master (typically a microcontroller) initiates data transfer on the bus and generates to permit that transfer. A master device communicates to the by transmitting the proper address followed by command and/or data words. Each transmit sequence is framed by a START (S) or REPEATED START (S r ) condition and a STOP (P) condition. Each word transmitted over the bus is 8 bits long and is always followed by an acknowledge clock pulse. 7

Voltage-Output Table 1. Power-Down Command Bits POWER-DOWN COMMAND BITS PD1 PD 1 1 1 1 MODE/FUNCTION Power-up device. output restored to previous value. Power-down mode. Power down device with output floating. Power-down mode 1. Power down device with output terminated with 1kΩ to GND. Power-down mode 2. Power down device with output terminated with 1kΩ to GND. The and drivers are open-drain outputs, requiring a pullup resistor to generate a logic high voltage (see the Typical Operating Circuit). Series resistors R S are optional. These series resistors protect the input stages of the from high-voltage spikes on the bus lines, and minimize crosstalk and undershoot of the bus signals. Bit Transfer One data bit is transferred during each clock cycle. The data on must remain stable during the high period of the clock pulse. Changes in while is high are control signals (see the START and STOP Conditions section). Both and idle high when the I 2 C bus is not busy. START and STOP Conditions When the serial interface is inactive, and idle high. A master device initiates communication by issuing a START condition. A START condition is a high-tolow transition on with high. A STOP condition is a low-to-high transition on, while is high (Figure 2). A START condition from the master signals the beginning of a transmission to the. The master terminates transmission by issuing a not acknowledge followed by a STOP condition (see the Acknowledge Bit (ACK) section). The STOP condition frees the bus. If a repeated START condition (Sr) is generated instead of a STOP condition, the bus remains active. When a STOP condition or incorrect address is detected, the internally disconnects from the serial interface until the next START condition, minimizing digital noise and feedthrough. Early STOP Conditions The recognizes a STOP condition at any point during transmission except if a STOP condition occurs in the same high pulse as a START condition (Figure 3). This condition is not a legal I 2 C format; at least one clock pulse must separate any START and STOP conditions. Repeated START Conditions A repeated START (S r ) condition may indicate a change of data direction on the bus. Such a change occurs when a command word is required to initiate a read operation. S r may also be used when the bus master is writing to several I 2 C devices and does not want to relinquish control of the bus. The serial interface supports continuous write operations with or without an S r condition separating them. Continuous read operations require S r conditions because of the change in direction of data flow. t SU, DAT t SU, STA t SP t BUF t LOW t HD, DAT t HD, STA t SU, STO t HIGH t HD, STA t R t F START CONDITION REPEATED START CONDITION STOP CONDITION START CONDITION Figure 1. 2-Wire Serial-Interface Timing Diagram 8

Voltage-Output S S r P Figure 2. START and STOP Conditions waits for a START condition followed by its slave address. The serial interface compares each address value bit-by-bit, allowing the interface to power down immediately if an incorrect address is detected. The LSB of the address word is the Read/Write (R/W) bit. R/W indicates whether the master is writing to or reading from the (R/W = selects the write condition, R/W = 1 selects the read condition). After receiving the proper address, the issues an ACK by pulling low for one clock cycle. The has four different factory/user-programmed addresses (Table 2). Address bits A6 through A1 are preset, while A is controlled by ADD. Connecting ADD to GND sets A =. Connecting ADD to sets A = 1. This feature allows up to four s to share the same bus. Table 2. I2C Slave Addresses STOP START LEGAL STOP CONDITION DEVICE ADDRESS PART V ADD (A6 A) L GND 111 L 111 1 M GND 111 M 111 1 START Figure 3. Early STOP Conditions ILLEGAL STOP ILLEGAL EARLY STOP CONDITION Acknowledge Bit (ACK) The acknowledge bit (ACK) is the ninth bit attached to any 8-bit data word. ACK is always generated by the receiving device. The generates an ACK when receiving an address or data by pulling low during the ninth clock period. When transmitting data, the waits for the receiving device to generate an ACK. Monitoring ACK allows for detection of unsuccessful data transfers. An unsuccessful data transfer occurs if a receiving device is busy or if a system fault has occurred. In the event of an unsuccessful data transfer, the bus master should reattempt communication at a later time. Slave Address A bus master initiates communication with a slave device by issuing a START condition followed by the 7- bit slave address (Figure 4). When idle, the Write Data Format In write mode (R/W = ), data that follows the address byte controls the (Figure 5). Bits C3 C configure the (Table 3). Bits D7 D are data. Bits S3 S are sub-bits and are always. Input and registers update on the falling edge of during the acknowledge bit. Should the write cycle be prematurely aborted, data is not updated and the write cycle must be repeated. Figure 6 shows two examplewrite data sequences. Extended Command Mode The features an extended command mode that is accessed by setting C3 C = 1 and D7 D4 =. S A6 A5 A4 A3 A2 A1 A R/W Figure 4. Slave-Address Byte Definition C3 C2 C1 C D7 D6 D5 D4 Figure 5. Command-Byte Definition 9

Voltage-Output S LSB LSB A6 A5 A4 A3 A2 A1 A R/W ACK C3 C2 C1 C D7 D6 D5 D4 LSB D3 D2 D1 D S3 S2 S1 S ACK P ACK EXAMPLE-WRITE SEQUENCE LSB LSB S A6 A5 A4 A3 A2 A1 A R/W ACK C3 C2 C1 C D7 D6 D5 D4 ACK LSB X X X X B A PD1 PD ACK P Figure 6. Example-Write Command Sequences EXAMPLE-WRITE TO POWER-DOWN REGISTER SEQUENCE The next command word writes to the power-down registers (Figure 7). Setting bits A or B to 1 sets that to the selected power-down mode based on the states of PD and PD1 (Table 1). Any combination of the s can be controlled with a single write sequence. Read Data Format In read mode (R/W = 1), the writes the contents of the register to the bus. The direction of data flow reverses following the address acknowledge by the. The device transmits the first byte of data, waits for the master to acknowledge, then transmits the second byte. Figure 8 shows an example-read data sequence. I 2 C Compatibility The is compatible with existing I 2 C systems. and are high-impedance inputs; has an open drain that pulls the data line low during the ninth clock pulse. The Typical Operating Circuit shows a typical I 2 C application. The communication protocol supports the standard I 2 C 8-bit communications. The general call address is ignored. The address is compatible with the 7-bit I 2 C addressing protocol only. No 1-bit address formats are supported. Digital-Feedthrough Suppression When the detects an address mismatch, the serial interface disconnects the signal from the core circuitry. This minimizes digital feedthrough X X X X B A PD1 PD Figure 7. Extended Command Byte Format caused by the signal on a static output. The serial interface reconnects the signal once a valid START condition is detected. Applications Information Digital Inputs and Interface Logic The 2-wire digital interface is I 2 C/SMBus compatible. The two digital inputs ( and ) load the digital input serially into the. Schmitt-trigger buffered inputs allow slow-transition interfaces, such as optocouplers to interface directly to the device. The digital inputs are compatible with CMOS logic levels. Power-Supply Bypassing and Ground Management Careful PC board layout is important for optimal system performance. Keep analog and digital signals separate to reduce noise injection and digital feedthrough. Use a ground plane to ensure that the ground return from GND to the power-supply ground is short and low impedance. Bypass with a.1µf capacitor to ground as close to the device as possible. 1

Voltage-Output Table 3. Command Byte Definitions SERIAL INPUT C3 C2 C1 C D7 D6 D5 D4 1 FUNCTION Load A input and registers with new data. Contents of B input registers are transferred to the register. All outputs are updated. Load B input and registers with new data. Contents of A input registers are transferred to the register. All outputs are updated. 1 Load A input register with new data. outputs remain unchanged. 1 1 Load B input register with new data. outputs remain unchanged. 1 Data in all input registers is transferred to respective registers. All outputs are updated simultaneously. New data is loaded into A input register. 1 1 Data in all input registers is transferred to respective registers. All outputs are updated simultaneously. New data is loaded into B input register. 1 1 Load all s with new data and update all outputs simultaneously. Both input and registers are updated with new data. 1 1 1 1 1 1 X X X X 1 1 1 1 1 1 1 1 1 1 1 1 1 1 Load all input registers with new data. outputs remain unchanged. Update all outputs simultaneously. Device ignores D7 D4. Do not send the data byte. Extended command mode. The next word writes to the power-down registers (see the Extended Command Mode section). Read A data. The device expects an S r condition followed by an address word with R/W = 1. Read B data. The device expects an S r condition followed by an address word with R/W = 1. 11

Voltage-Output LSB LSB R/W S A6 A5 A4 A3 A2 A1 A ACK C3 C2 C1 C D7 D6 D5 D4 = Sr A6 A5 A4 A3 A2 A1 A BYTES GENERATED BY MASTER DEVICE LSB R/W = 1 ACK LSB X X PD1 PD D7 D6 D5 D4 ACK ACK BYTES GENERATED BY ACK GENERATED BY MASTER DEVICE LSB D3 D2 D1 D S3 S2 S1 S ACK P Figure 8. Example-Read Word Data Sequence Functional Diagram REF INPUT REGISTER A MUX AND REGISTER 8-BIT A OUTA RESISTOR NETWORK INPUT REGISTER B MUX AND REGISTER 8-BIT B OUTB RESISTOR NETWORK SERIAL INTERFACE POWER-DOWN CIRCUITRY ADD GND Chip Information TRANSISTOR COUNT: 11,186 PROCESS: BiCMOS 12

Voltage-Output.6±.1.6±.1 8 1 Ø.5±.1 D E H 4X S BOTTOM VIEW 8 1 DIM A A1 Package Information INCHES MIN MAX -.43.2.6.37.1.14.5.7.116.12.256 BSC A2.3 b c D e E.116 H.188 L.16 α S.27 BSC.12.198.26 6 MILLIMETERS MIN MAX - 1.1.5.15.75.95.25.36.13.18 2.95 3.5.65 BSC 2.95 3.5 4.78 5.3.41.66 6.525 BSC 8LUMAXD.EPS TOP VIEW A2 A1 A e b c L α FRONT VIEW SIDE VIEW PROPRIETARY INFORMATION TITLE: PACKAGE OUTLINE, 8L umax/usop APPROVAL DOCUMENT CONTROL NO. REV. 21-36 J 1 1 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, 12 San Gabriel Drive, Sunnyvale, CA 9486 48-737-76 13 25 Maxim Integrated Products Printed USA is a registered trademark of Maxim Integrated Products, Inc.