19-4744; Rev 1; 7/09 Two-/Four-Channel, I2C, 7-Bit Sink/Source Current DAC The DS4422 and DS4424 contain two or four I2C programmable current DACs that are each capable of sinking and sourcing current up to 200µA. Each DAC output has 127 sink and 127 source settings that are programmed using the I2C interface. The current DAC outputs power up in a high-impedance state. Features ♦ Two (DS4422) or Four (DS4424) Current DACs ♦ Full-Scale Current 50µA to 200µA ♦ Full-Scale Range for Each DAC Determined by External Resistors ♦ 127 Settings Each for Sink and Source Modes Applications ♦ I2C-Compatible Serial Interface Power-Supply Margining ♦ Two Address Pins Allow Four Devices on Same I2C Bus Adjustable Current Sink or Source ♦ Low Cost Power-Supply Adjustment ♦ Small Package (14-Pin, 3mm x 3mm TDFN) Ordering Information OUTPUTS TEMP RANGE PINPACKAGE DS4422N+ 2 -40°C to +85°C 14 TDFN-EP DS4422N+T&R 2 -40°C to +85°C 14 TDFN-EP DS4424N+ 4 -40°C to +85°C 14 TDFN-EP DS4424N+T&R 4 -40°C to +85°C 14 TDFN-EP PART ♦ -40°C to +85°C Temperature Range ♦ 2.7V to 5.5V Operating Range Pin Configuration appears at end of data sheet. +Denotes a lead(Pb)-free/RoHS-compliant package. T&R = Tape and reel. EP = Exposed pad. Typical Operating Circuit VCC VOUT0 VOUT1 RPU RPU OUT VCC SDA SCL DC-DC CONVERTER A1 A0 GND DS4422/ DS4424 R0A FB DC-DC CONVERTER R1A FB OUT1 R0B FS0 RFS0 OUT0 OUT R1B FS1 RFS1 _______________________________________________________________ Maxim Integrated Products For pricing, delivery, and ordering information, please contact Maxim Direct at 1-888-629-4642, or visit Maxim’s website at www.maxim-ic.com. 1 DS4422/DS4424 General Description DS4422/DS4424 Two-/Four-Channel, I2C, 7-Bit Sink/Source Current DAC ABSOLUTE MAXIMUM RATINGS Voltage Range on VCC, SDA, and SCL Relative to Ground.............................................-0.5V to +6.0V Voltage Range on A0, A1, FS0, FS1, FS2, FS3, OUT0, OUT1, OUT2, and OUT3 Relative to Ground ................-0.5V to (VCC + 0.5V) (Not to exceed 6.0V.) Operating Temperature Range ...........................-40°C to +85°C Storage Temperature Range .............................-55°C to +125°C Soldering Temperature ...............................Refer to the IPC/JEDEC J-STD-020 Specification. 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. RECOMMENDED OPERATING CONDITIONS (TA = -40°C to +85°C.) PARAMETER SYMBOL Supply Voltage VCC Input Logic 1 (SDA, SCL, A0, A1) VIH Input Logic 0 (SDA, SCL, A0, A1) VIL Full-Scale Resistor Values CONDITIONS (Note 1) MIN TYP 2.7 0.7 x VCC -0.3 RFS0, RFS1, (Note 2) RFS2, RFS3 MAX UNITS 5.5 V VCC + 0.3 V 0.3 x VCC V 40 160 k MAX UNITS DC ELECTRICAL CHARACTERISTICS (VCC = +2.7V to +5.5V, TA = -40°C to +85°C.) PARAMETER SYMBOL CONDITIONS Supply Current ICC VCC = 5.5V (Note 3) Input Leakage (SDA, SCL) I IL VCC = 5.5V Output Leakage (SDA) IL Output Current Low (SDA) I OL RFS Voltage VRFS I/O Capacitance CI/O MIN TYP DS4422 250 DS4424 250 VOL = 0.4V 3 VOL = 0.6V 6 μA 1 μA 1 μA mA 0.976 V 10 pF OUTPUT CURRENT SOURCE CHARACTERISTICS (VCC = +2.7V to +5.5V, TA = -40°C to +85°C.) PARAMETER SYMBOL Output Voltage for Sinking Current VOUT:SINK Output Voltage for Sourcing Current Full-Scale Sink Output Current CONDITIONS (Note 4) VOUT:SOURCE (Note 4) IOUT:SINK (Notes 1, 4) Full-Scale Source Output Current IOUT:SOURCE (Notes 1, 4) Output Current Full-Scale Accuracy I OUT:FS +25°C, VCC = 3.3V; using 0.1% RFS resistor (Note 2), VOUT0 = VOUT1 = 1.2V Output Current Temperature Coefficient I OUT:TC (Note 5) 2 MIN MAX UNITS 0.5 TYP 3.5 V 0 VCC 0.75 V 50 200 μA -200 -50 μA ±6 % ±75 _______________________________________________________________________________________ ppm/°C Two-/Four-Channel, I2C, 7-Bit Sink/Source Current DAC DS4422/DS4424 OUTPUT CURRENT SOURCE CHARACTERISTICS (continued) (VCC = +2.7V to +5.5V, TA = -40°C to +85°C.) PARAMETER SYMBOL CONDITIONS MIN TYP Output Current Variation Due to Power-Supply Change DC source 0.32 DC sink 0.42 Output Current Variation Due to Output-Voltage Change DC source, V OUT measure at 1.2V 0.16 DC sink, VOUT measure at 1.2V 0.16 Output Leakage Current at Zero Current Setting I ZERO MAX UNITS %/V %/V -1 +1 μA Output Current Differential Linearity DNL (Notes 6, 7) -0.5 +0.5 LSB Output Current Integral Linearity INL (Notes 7, 8) -1 +1 LSB MAX UNITS 400 kHz AC ELECTRICAL CHARACTERISTICS (VCC = +2.7V to +5.5V, TA = -40°C to +85°C.) PARAMETER SYMBOL CONDITIONS (Note 9) MIN TYP SCL Clock Frequency f SCL 0 Bus Free Time Between STOP and START Conditions tBUF 1.3 μs Hold Time (Repeated) START Condition tHD:STA 0.6 μs Low Period of SCL tLOW 1.3 μs High Period of SCL tHIGH 0.6 μs Data Hold Time tDH:DAT 0 Data Setup Time t SU:DAT 100 START Setup Time t SU:STA 0.9 μs ns 0.6 μs SDA and SCL Rise Time tR (Note 10) 20 + 0.1CB 300 ns SDA and SCL Fall Time tF (Note 10) 20 + 0.1CB 300 ns STOP Setup Time t SU:STO SDA and SCL Capacitive Loading CB 0.6 (Note 10) μs 400 pF All voltages with respect to ground. Currents entering the IC are specified positive, and currents exiting the IC are negative. Input resistors (RFS) must be between the speciifed values to ensure the device meets its accuracy and linearity specifications. Supply current specified with all outputs set to zero current setting. A0 and A1 are connected to GND. SDA and SCL are connected to VCC. Excludes current through RFS resistors (IRFS). Total current including IRFS is ICC + (2 x IRFS). Note 4: The output-voltage range must be satisfied to ensure the device meets its accuracy and linearity specifications. Note 5: Temperature drift excludes drift caused by external resistor. Note 6: Differential linearity is defined as the difference between the expected incremental current increase with respect to position and the actual increase. The expected incremental increase is the full-scale range divided by 127. Note 7: Guaranteed by design. Note 8: Integral linearity is defined as the difference between the expected value as a function of the setting and the actual value. The expected value is a straight line between the zero and the full-scale values proportional to the setting. Note 9: Timing shown is for fast-mode (400kHz) operation. This device is also backward compatible with I2C standard-mode timing. Note 10: CB—total capacitance of one bus line in pF. Note 1: Note 2: Note 3: _______________________________________________________________________________________ 3 Typical Operating Characteristics (TA = +25°C, unless otherwise noted.) SUPPLY CURRENT vs. TEMPERATURE 200 100 DOES NOT INCLUDE CURRENT DRAWN BY RESISTORS CONNECTED TO FS0, FS1, FS2, OR FS3 -175 150 VCC = 3.3V VCC = 2.7V DOES NOT INCLUDE CURRENT DRAWN BY RESISTORS CONNECTED TO FS0, FS1, FS2, OR FS3 50 0 3.0 3.5 4.0 4.5 5.0 5.5 -250 -40 -20 0 20 40 60 0 80 VOUT (V) VOLTCO (SINK) TEMPERATURE COEFFICIENT vs. SETTING (SOURCE) TEMPERATURE COEFFICIENT vs. SETTING (SINK) 225 200 175 150 150 100 +25°C TO -40°C 50 0 +25°C TO +85°C -50 -100 0.5 1.0 1.5 2.0 2.5 3.0 3.5 4.0 -50 +25°C TO +85°C -100 -150 -200 FOR THE 50μA TO 200μA CURRENT SINK RANGE 25 50 75 100 0 125 25 50 SETTING (DEC) DIFFERENTIAL LINEARITY 1.0 DS4422/4 toc07 FOR THE 50μA TO 200μA CURRENT SOURCE AND SINK RANGE 75 SETTING (DEC) INTEGRAL LINEARITY 1.00 FOR THE 50μA TO 200μA CURRENT SOURCE AND SINK RANGE 0.8 0.6 0.50 0.4 0.25 DNL (LSB) INL (LSB) +25°C TO -40°C 0 -250 0 VOUT (V) 0.75 50 0 -0.25 0.2 0 -0.2 -0.4 -0.50 -0.6 -0.75 -0.8 -1.0 -1.00 0 25 50 75 SETTING (DEC) 100 DS4422/4 toc06 FOR THE 50μA TO 200μA CURRENT SOURCE RANGE TEMPERATURE COEFFICIENT (°C/ppm) TEMPERATURE COEFFICIENT (°C/ppm) DS4422/4 toc04 200 DS4422/4 toc05 TEMPERATURE (°C) 40kΩ LOAD ON FS0, FS1, FS2, AND FS3 0 0.5 1.0 1.5 2.0 2.5 3.0 3.5 4.0 4.5 5.0 SUPPLY VOLTAGE (V) 250 4 -225 0 2.5 -200 100 DS4422/4 toc08 50 40kΩ LOAD ON FS0, FS1, FS2, AND FS3 IOUT (μA) 150 -150 DS4422/4 toc02 VCC = 5.0V SUPPLY CURRENT (μA) SUPPLY CURRENT (μA) 200 VOLTCO (SOURCE) 250 DS4422/4 toc01 250 DS4422/4 toc03 SUPPLY CURRENT vs. SUPPLY VOLTAGE IOUT (μA) DS4422/DS4424 Two-/Four-Channel, I2C, 7-Bit Sink/Source Current DAC 125 0 25 50 75 100 125 SETTING (DEC) _______________________________________________________________________________________ 100 125 Two-/Four-Channel, I2C, 7-Bit Sink/Source Current DAC PIN NAME FUNCTION DS4424 DS4422 1 1 SDA I2C Serial Data. Input/output for I2C data. 2 2 SCL I2C Serial Clock. Input for I2C clock. 3 3 GND Ground 4 — FS3 5 — FS2 6 6 FS1 7 7 FS0 8 8 OUT0 10 10 OUT1 12 — OUT2 14 — OUT3 9, 11 9, 11 A0, A1 13 13 VCC Power Supply — 4, 5, 12, 14 N.C. No Connection — — EP Full-Scale Calibration Input. A resistor to ground on these pins determines the full-scale current for each output. FS0 controls OUT0, FS1 controls OUT1, etc. (The DS4422 has only two inputs: FS0 and FS1.) Current Output. Sinks or sources the current determined by the I2C interface and the resistance connected to FSx. (The DS4422 has only two outputs: OUT0 and OUT1.) Address Select Inputs. Determines the I2C slave address by connecting VCC or GND. See the Detailed Description section for the available device addresses. Exposed Pad. Connect to GND or leave unconnected. Block Diagram SDA SCL VCC A1 A0 I2C-COMPATIBLE SERIAL INTERFACE DS4422/DS4424 VCC F8h F9h SOURCE OR SINK MODE CURRENT DAC0 GND 127 POSITIONS EACH FOR SINK AND SOURCE MODE FS0 RFS0 CURRENT DAC1 CURRENT DAC3 CURRENT DAC2 FS1 OUT0 FBh FAh FS3 FS2 RFS1 OUT1 RFS2 OUT2 RFS3 OUT3 DS4424 ONLY _______________________________________________________________________________________ 5 DS4422/DS4424 Pin Description DS4422/DS4424 Two-/Four-Channel, I2C, 7-Bit Sink/Source Current DAC Detailed Description The DS4422/DS4424 contain two or four I2C adjustable current sources that are each capable of sinking and sourcing current. Each output (OUT0, OUT1, OUT2, and OUT3) has 127 sink and 127 source settings that can be controlled by the I2C interface. The full-scale ranges and corresponding step sizes of the outputs are determined by external resistors, connected to pins FS0, FS1, FS2, and FS3, that can adjust the output current over a 4:1 range. Pins OUT2, OUT3, FS2, and FS3 are only available on the DS4424. The formula to determine RFS (connected to the FSx pins) to attain the desired full-scale current range is: Equation 1: I2C Slave Address The DS4422/DS4424 respond to one of four I2C slave addresses determined by the two address inputs, A0 and A1. The address inputs should be connected to either VCC or ground. Table 1 lists the slave addresses determined by the address input combinations. Table 1. Slave Addresses A1 A0 SLAVE ADDRESS (HEX) GND GND 20h GND VCC 60h VCC GND A0h VCC VCC E0h V RFS = RFS × 127 16 × IFS Where IFS is the desired full-scale current value, VRFS is the RFS voltage (see the DC Electrical Characteristics table), and RFS is the external resistor value. To calculate the output current value (IOUT) based on the corresponding DAC value (see Table 1 for corresponding memory addresses), use equation 2. Equation 2: IOUT = Table 2. Memory Addresses MEMORY ADDRESS (HEX) CURRENT SOURCE F8h OUT0 DAC Value(dec) × IFS 127 On power-up the DS4422/DS4424 output zero current. This is done to prevent them from sinking or sourcing an incorrect amount of current before the system host controller has had a chance to modify the device’s setting. As a source for biasing instrumentation or other circuits, the DS4422/DS4424 provide a simple and inexpensive current source with an I2C interface for control. The adjustable full-scale range allows the application to get the most out of its 7-bit sink or source resolution. When used in adjustable power-supply applications (see Typical Operating Circuit), the DS4422/DS4424 do not affect the initial power-up voltage of the supply because they default to providing zero output current on power-up. As the devices source or sink current into the feedback-voltage node, they change the amount of output voltage required by the regulator to reach its steadystate operating point. Using the external resistor, RFS, to set the output current range, the DS4422/DS4424 provide some flexibility for adjusting the impedances of the feedback network or the range over which the power supply can be controlled or margined. 6 Memory Organization To control the DS4422/DS4424’s current sources, write to the memory addresses listed in Table 2. F9h OUT1 FAh* OUT2* FBh* OUT3* *Only for DS4424. The format of each output control register is given by: MSB LSB S D6 D5 D4 D3 D2 D1 D0 Where: BIT NAME FUNCTION POWER-ON DEFAULT S Sign Bit Determines if DAC sources or sinks current. For sink S = 0; for source S = 1. 0b Data 7-Bit Data Controlling DAC Output. Setting 0000000b outputs zero current regardless of the state of the sign bit. 0000000b DX _______________________________________________________________________________________ Two-/Four-Channel, I2C, 7-Bit Sink/Source Current DAC IFS = (0.976V/80kΩ) x (127/16) = 96.838µA The MSB of the output register is 1, so the output is sourcing the value corresponding to position 2Ah (42 decimal). The magnitude of the output current is equal to: 96.838µA x (42/127) = 32.025µA I2C Serial Interface Description I2C Definitions The following terminology is commonly used to describe I2C data transfers: I 2 C Slave Address: The slave address of the DS4422/DS4424 is determined by the state of the A0 and A1 pins (see Table 1). Master Device: The master device controls the slave devices on the bus. The master device generates SCL clock pulses and START and STOP conditions. Slave Devices: Slave devices send and receive data at the master’s request. Bus Idle or Not Busy: Time between STOP and START conditions when both SDA and SCL are inactive and in their logic-high states. When the bus is idle it often initiates a low-power mode for slave devices. START Condition: A START condition is generated by the master to initiate a new data transfer with a slave. Transitioning SDA from high to low while SCL remains high generates a START condition. See Figure 1 for applicable timing. STOP Condition: A STOP condition is generated by the master to end a data transfer with a slave. Transitioning SDA from low to high while SCL remains high generates a STOP condition. See Figure 1 for applicable timing. Repeated START Condition: The master can use a repeated START condition at the end of one data transfer to indicate that it will immediately initiate a new data transfer following the current one. Repeated STARTs are commonly used during read operations to identify a specific memory address to begin a data transfer. A repeated START condition is issued identically to a normal START condition. See Figure 1 for applicable timing. Bit Write: Transitions of SDA must occur during the low state of SCL. The data on SDA must remain valid and unchanged during the entire high pulse of SCL, plus the setup and hold time requirements (Figure 1). Data is shifted into the device during the rising edge of the SCL. Bit Read: At the end of a write operation, the master must release the SDA bus line for the proper amount of setup time (Figure 1) before the next rising edge of SCL during a bit read. The device shifts out each bit of data on SDA at the falling edge of the previous SCL pulse and the data bit is valid at the rising edge of the current SCL pulse. Remember that the master generates all SCL clock pulses, including when it is reading bits from the slave. Acknowledgement (ACK and NACK): An Acknowledgement (ACK) or Not Acknowledge (NACK) is always the ninth bit transmitted during a byte transfer. The device receiving data (the master during a read or the slave during a write operation) performs an ACK by transmitting a zero during the ninth bit. A device performs a SDA tBUF tHD:STA tLOW tR tSP tF SCL tHD:STA STOP tSU:STA tHIGH tSU:DAT START REPEATED START tSU:STO tHD:DAT NOTE: TIMING IS REFERENCED TO VIL(MAX) AND VIH(MIN). Figure 1. I2C Timing Diagram _______________________________________________________________________________________ 7 DS4422/DS4424 Example: RFS0 = 80kΩ and register 0xF8h is written to a value of 0xAAh. Calculate the output current. DS4422/DS4424 Two-/Four-Channel, I2C, 7-Bit Sink/Source Current DAC TYPICAL I2C WRITE TRANSACTION MSB START A1 LSB A0 1 0 0 0 0 R/W MSB SLAVE ACK b7 READ/ WRITE SLAVE ADDRESS* LSB b6 b5 b4 b3 b2 b1 b0 MSB SLAVE ACK b7 LSB b6 b5 b4 REGISTER/MEMORY ADDRESS b3 b2 b1 b0 SLAVE ACK STOP DATA *THE SLAVE ADDRESS IS DETERMINED BY ADDRESS PINS A0 AND A1. EXAMPLE I2C TRANSACTIONS (WHEN A0 AND A1 ARE GROUNDED) 20h F9h A) SINGLE BYTE WRITE -WRITE REGISTER F9h TO 00h START 0 0 1 0 0 0 0 0 SLAVE 1 1 1 1 1 0 0 1 ACK B) SINGLE BYTE READ -READ REGISTER F8h START 0 0 1 0 0 0 0 0 SLAVE 1 1 1 1 1 0 0 0 SLAVE ACK ACK 20h SLAVE 0 0 0 0 0 0 0 0 ACK F8h SLAVE ACK STOP 21h REPEATED START 0 0 1 0 0 0 0 1 SLAVE ACK DATA MASTER NACK STOP Figure 2. I2C Communication Examples NACK by transmitting a one during the ninth bit. Timing for the ACK and NACK is identical to all other bit writes (Figure 2). An ACK is the acknowledgment that the device is properly receiving data. A NACK is used to terminate a read sequence or as an indication that the device is not receiving data. Byte Write: A byte write consists of 8 bits of information transferred from the master to the slave (most significant bit first) plus a 1-bit acknowledgement from the slave to the master. The 8 bits transmitted by the master are done according to the bit-write definition, and the acknowledgement is read using the bit-read definition. Byte Read: A byte read is an 8-bit information transfer from the slave to the master plus a 1-bit ACK or NACK from the master to the slave. The 8 bits of information that are transferred (most significant bit first) from the slave to the master are read by the master using the bit-read definition above, and the master transmits an ACK using the bit write definition to receive additional data bytes. The master must NACK the last byte read to terminated communication so the slave will return control of SDA to the master. Slave Address Byte: Each slave on the I 2 C bus responds to a slave address byte sent immediately following a START condition. The slave address byte contains the slave address in the most significant 7 bits and the R/W bit in the least significant bit. The DS4422/DS4424 slave address is determined by the 8 state of the A0 and A1 address pins. Table 1 describes the addresses corresponding to the state of A0 and A1. When the R/W bit is 0 (such as in A0h), the master is indicating that it will write data to the slave. If R/W = 1 (A1h in this case), the master is indicating that it wants to read from the slave. If an incorrect slave address is written, the DS4422/DS4424 assume the master is communicating with another I 2 C device and ignore the communication until the next START condition is sent. Memory Address: During an I2C write operation, the master must transmit a memory address to identify the memory location where the slave is to store the data. The memory address is always the second byte transmitted during a write operation following the slave address byte. I2C Communication Writing to a Slave: The master must generate a START condition, write the slave address byte (R/W = 0), write the memory address, write the byte of data, and generate a STOP condition. Remember that the master must read the slave’s acknowledgement during all byte-write operations. Reading from a Slave: To read from the slave, the master generates a START condition, writes the slave address byte with R/W = 1, reads the data byte with a NACK to indicate the end of the transfer, and generates a STOP condition. _______________________________________________________________________________________ Two-/Four-Channel, I2C, 7-Bit Sink/Source Current DAC DS4422/DS4424 VCC VOUT* = 2.0V 4.7kΩ 4.7kΩ OUT VCC SDA SCL A1 A0 GND DC-DC CONVERTER DS4422/ DS4424 I0A R0A = 4.00kΩ FB OUT0 VFB* = 0.8V I0B R0B= 2.67kΩ FS0 IOUT0 RFS0 = 80kΩ *VOUT AND VFB VALUES ARE DETERMINED BY THE DC-DC CONVERTER AND SHOULD NOT BE CONFUSED WITH VOUT AND VRFS OF THE DS4422/DS4424. Figure 3. Example Application Circuit Applications Information Example Calculations for an Adjustable Power Supply In this example, the Typical Operating Circuit is used as a base to create Figure 3, a DC-DC output voltage of 2.0V with ±20% margin. The adjustable power supply has a DC-DC converter output voltage, VOUT, of 2.0V and a DC-DC converter feedback voltage, VFB, of 0.8V. To determine the relationship of R0A and R0B, start with the equation: VFB = R0B × VOUT R0A + R0B Substituting VFB = 0.8V and VOUT = 2.0V, the relationship between R0A and R0B is determined to be: R0A ≈ 1.5 x R0B IOUT0 is chosen to be 100µA (midrange source/sink current for the DS4422/DS4424). Summing the currents into the feedback node produces the following: IOUT0 = IR0B - IR0A Where: V IR0B = FB R0B And: V − VFB IR0A = OUT R0A To create a 20% margin in the supply voltage, the value of VOUT is set to 2.4V. With these values in place, R0B is calculated to be 2.67kΩ, and R0A is calculated to be 4.00kΩ. The current DAC in this configuration allows the output voltage to be moved linearly from 1.6V to 2.4V using 127 settings. This corresponds to a resolution of 6.3mV/step. VCC Decoupling To achieve the best results when using the DS4422/ DS4424, decouple the power supply with a 0.01µF or 0.1µF capacitor. Use a high-quality ceramic surfacemount capacitor if possible. Surface-mount components minimize lead inductance, which improves performance, and ceramic capacitors tend to have adequate high-frequency response for decoupling applications. Power Rail Considerations Given that the absolute maximum rating for the OUT pins is VCC + 0.5V, it is recommended that the DS4424 power rail be brought up before or at the same time as the power rail of the source it is controlling. _______________________________________________________________________________________ 9 Two-/Four-Channel, I2C, 7-Bit Sink/Source Current DAC DS4422/DS4424 Pin Configuration Package Information For the latest package outline information, go to www.maxim-ic.com/packages. TOP VIEW 1 14 OUT3 (N.C.) SCL 2 13 VCC 12 OUT2 (N.C.) 11 A1 10 OUT1 9 A0 8 OUT0 GND 3 FS3 (N.C.) 4 FS2 (N.C.) 5 FS1 6 + SDA DS4422/ DS4424 PACKAGE TYPE PACKAGE CODE DOCUMENT NO. 14 TDFN-EP T1433+2 21-0137 *EP FS0 7 ( ) INDICATES DS4422 ONLY. *EXPOSED PAD 10 ______________________________________________________________________________________ Two-/Four-Channel, I2C, 7-Bit Sink/Source Current DAC PAGES CHANGED REVISION NUMBER REVISION DATE 0 3/08 Initial release. — 1 7/09 Added the Power Rail Considerations section. 9 DESCRIPTION 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 ____________________ 11 © 2009 Maxim Integrated Products Maxim is a registered trademark of Maxim Integrated Products, Inc. DS4422/DS4424 Revision History