DS4432

DS4432 MAXIM | Alldatasheet

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Technical content

Features

♦ Two 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 ♦ I2C-Compatible Serial Interface ♦ Low Cost ♦ Small Package (8-Pin µSOP) ♦ -40°C to +85°C Temperature Range ♦ 2.7V to 5.5V Operating Range DC-DC CONVERTER FB OUT SDA SCL OUT0 OUT1 GND RFS0 RFS1 4.7kΩ4.7kΩ VCC VCC VOUT0 FS0 FS1 R0B R0A DC-DC CONVERTER FB OUT VOUT1 R1B R1A DS4432 Typical Operating Circuit

Ordering Information

+Denotes a lead(Pb)-free/RoHS-compliant package. T&R = Tape and reel. PART TEMP RANGE PIN-PACKAGE DS4432U+ -40°C to +85°C 8 μSOP DS4432U+T&R -40°C to +85°C 8 μSOP TOP VIEW DS4432 μSOP 2 7 OUT1SCL

18 V CCSDA

Dual-Channel, I2C, 7-Bit Sink/Source Current DAC ABSOLUTE MAXIMUM RATINGS RECOMMENDED OPERATING CONDITIONS (TA = -40°C to +85°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 specificatio ns is not implied. Exposure to absolute maximum rating conditions for extended periods may affect device reliability. Voltage Range on VCC, SDA, and SCL Voltage Range on FS0, FS1, OUT0, OUT1 (Not to exceed 6.0V.) J-STD-020 Specification. PARAMETER SYMBOL CONDITIONS MIN TYP MAX UNITS Supply Voltage V CC (Note 1) 2.7 5.5 V Input Logic 1 (SDA, SCL) V IH 0.7 x V CC V CC + 0.3 V Input Logic 0 (SDA, SCL) V IL -0.3 0.3 x V CC V Full-Scale Resistor Values R FS0, RFS1 (Note 2) 40 160 k DC ELECTRICAL CHARACTERISTICS (VCC = +2.7V to +5.5V, TA = -40°C to +85°C.) PARAMETER SYMBOL CONDITIONS MIN TYP MAX UNITS Supply Current I CC V CC = 5.5V (Note 3) 150 μA Input Leakage (SDA, SCL) I IL V CC = 5.5V 1 μA Output Leakage (SDA) I L 1 μA VOL = 0.4V 3 Output Current Low (SDA) I OL VOL = 0.6V 6 mA RFS Voltage V RFS 0.997 V I/O Capacitance C I/O 10 pF OUTPUT CURRENT SOURCE CHARACTERISTICS (VCC = +2.7V to +5.5V, TA = -40°C to +85°C.) PARAMETER SYMBOL CONDITIONS MIN TYP MAX UNITS Output Voltage for Sinking Current V OUT:SINK (Note 4) 0.5 3.5 V Output Voltage for Sourcing Current VOUT:SOURCE (Note 4) 0 VCC - 0.75 V Full-Scale Sink Output Current I OUT:SINK (Notes 1, 4) 50 200 μA Full-Scale Source Output Current I OUT:SOURCE (Notes 1, 4) -200 -50 μA Output Current Full-Scale Accuracy IOUT:FS +25°C, VCC = 3.3V; using 0.1% R FS resistor, V OUT0 = VOUT1 = 1.2V (Note 2) ±5 % Output Current Temperature Coefficient IOUT:TC (Note 5) ±130 ppm/°C

Dual-Channel, I2C, 7-Bit Sink/Source Current DAC Note 1: All voltages with respect to ground. Currents entering the IC are specified positive, and currents exiting the IC are negative. Note 2: Input resistors (RFS) must be between the specified values to ensure the device meets its accuracy and linearity specifications. Note 3: Supply current specified with all outputs set to zero current setting. 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. OUTPUT CURRENT SOURCE CHARACTERISTICS (continued) (VCC = +2.7V to +5.5V, TA = -40°C to +85°C.) PARAMETER SYMBOL CONDITIONS MIN TYP MAX UNITS DC source, VOUT measured at 1.2V 0.41 Output Current Variation Due to Power-Supply Change DC sink, V OUT measured at 1.2V 0.41 %/V DC source, VCC = 3.3V 0.08 Output Current Variation Due to Output-Voltage Change DC sink, V CC = 3.3V 0.14 %/V Output Leakage Current at Zero Current Setting IZERO -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 AC ELECTRICAL CHARACTERISTICS (VCC = +2.7V to +5.5V, TA = -40°C to +85°C.) PARAMETER SYMBOL CONDITIONS MIN TYP MAX UNITS SCL Clock Frequency f SCL (Note 9) 0 400 kHz 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 t LOW 1.3 μs High Period of SCL t HIGH 0.6 μs Data Hold Time t HD:DAT 0 0.9 μs Data Setup Time t SU:DAT 100 ns START Setup Time t SU:STA 0.6 μs SDA and SCL Rise Time t R (Note 10) 20 + 0.1C B 300 ns SDA and SCL Fall Time t F (Note 10) 20 + 0.1C B 300 ns STOP Setup Time t SU:STO 0.6 μs SDA and SCL Capacitive Loading CB (Note 10) 400 pF

Dual-Channel, I2C, 7-Bit Sink/Source Current DAC Pin Description NAME PIN FUNCTION SDA 1 I 2C Serial Data. Input/output for I 2C data. SCL 2 I 2C Serial Clock. Input for I 2C clock. FS1 3 FS0 5 Full-Scale Calibration Inputs. A resistor to ground on these pins determines the full-scale current for each output. FS0 controls OUT0; FS1 controls OUT1. GND 4 Ground OUT0 6 OUT1 7 Current Outputs. Sinks or sources the current determined by the register settings and the resistance connected to FS0 and FS1. VCC 8 Power Supply Typical Operating Characteristics (Applies to OUT0 and OUT1. VCC = 2.7V to 5.0V, SDA = SCL = VCC, TA = +25°C, and no loads on OUT0, OUT1, FS0, or FS1, unless otherwise noted.) SUPPLY CURRENT vs. SUPPLY VOLTAGE DS4432 toc01 SUPPLY VOLTAGE (V) SUPPLY CURRENT (μA) 100 125 150 2.5 5.5 DOES NOT INCLUDE CURRENT DRAWN BY RESISTORS CONNECTED TO FS0 OR FS1. SUPPLY CURRENT vs. TEMPERATURE DS4432 toc02 TEMPERATURE (°C) SUPPLY CURRENT (μA) 60 8040200-20 100 125 150 -40 DOES NOT INCLUDE CURRENT DRAWN BY RESISTORS CONNECTED TO FS0 OR FS1. VCC = 5.5V VCC = 3.3V VCC = 2.7V VOLTCO (SOURCE) DS4432 toc03 VOUT (V) IOUT (μA) 4321 -225 -200 -175 -150 -250 40kΩ LOAD ON FS0 AND FS1. VOLTCO (SINK) DS4432 toc04 VOUT (V) IOUT (μA) 175 200 225 250 150 0 4.0 40kΩ LOAD ON FS0 AND FS1. TEMPERATURE COEFFICIENT vs. SETTING (SOURCE) DS4432 toc05 SETTING (DEC) TEMPERATURE COEFFICIENT (°C/ppm) 100 125755025 100 150 200 250 300 -50 RANGE FOR THE 50μA TO 200μA CURRENT SOURCE RANGE. +25°C TO -40°C +25°C TO +85°C TEMPERATURE COEFFICIENT vs. SETTING (SINK) DS4432 toc06 SETTING (DEC) TEMPERATURE COEFFICIENT (°C/ppm) 100 125755025 -150 -50 150 250 350 450 550 650 -250 RANGE FOR THE 50μA TO 200μA CURRENT SINK RANGE. +25°C TO -40°C +25°C TO +85°C

Dual-Channel, I2C, 7-Bit Sink/Source Current DAC Block Diagram VCC VCC RFS0 RFS1 SDA SCL GND FS0 FS1 OUT1OUT0 CURRENT DAC0 F8h F9h SOURCE OR SINK MODE 127 POSITIONS EACH FOR SINK AND SOURCE MODE CURRENT DAC1 I2C-COMPATIBLE SERIAL INTERFACE DS4432 Typical Operating Characteristics (continued) (Applies to OUT0 and OUT1. VCC = 2.7V to 5.0V, SDA = SCL = VCC, TA = +25°C, and no loads on OUT0, OUT1, FS0, or FS1, unless otherwise noted.) INTEGRAL LINEARITY DS4432 toc07 SETTING (DEC) INL (LSB) 100 125755025 -0.8 -0.6 -0.4 -0.2 0.2 0.4 0.6 0.8 1.0 -1.0 RANGE FOR THE 50μA TO 200μA CURRENT SOURCE AND SINK RANGE. DIFFERENTIAL LINEARITY DS4432 toc08 SETTING (DEC) DNL (LSB) 100 125755025 -0.8 -0.6 -0.4 -0.2 0.2 0.4 0.6 0.8 1.0 -1.0 RANGE FOR THE 50μA TO 200μA CURRENT SOURCE AND SINK RANGE.

that are each capable of sinking and sourcing current. tors, connected to pins FS0 and FS1. table), and RFS is the external resistor value. memory addresses), use equation 2. troller has had a chance to modify the DS4432’s setting. out of its 7-bit sink or source resolution. supply can be controlled or margined. memory addresses listed in Table 1. a value of 0xAAh. Calculate the output current. ing the value corresponding to position 2Ah (42 decimal). The DS4432’s slave address is 90h. SCL clock pulses and START and STOP conditions.

1 IOUT FS=× AC Value dec()

16 IFS RFS

Table 1. Memory Addresses of the state of the sign bit.

so the slave returns control of SDA to the master. DS4432’s slave address is 90h. Figure 2. I2C Communication Examples

Dual-Channel, I2C, 7-Bit Sink/Source Current DAC Maxim cannot assume responsibility for use of any circuitry other than circuitry entirely embodied in a Maxim product. No circu it 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 _____________________ 9 © 2008 Maxim Integrated Products is a registered trademark of Maxim Integrated Products, Inc. IOUT0 is chosen to be 100µA (midrange source/sink current for the DS4432). Summing the currents into the feedback node, we have the following: where and To create a 20% margin in the supply voltage, the value of V OUT is set to 2.4V. With these values in place, R 0B is calculated to be 2.67k Ω, and R0A is calculated to be 4kΩ. 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 DS4432, decouple the power supply with a 0.01µF or 0.1µF capacitor. Use a high-quality ceramic surface-mount capacitor if possible. Surface-mount components mini- mize lead inductance, which improves performance, and ceramic capacitors tend to have adequate high- frequency response for decoupling applications. I VV RRA OUT FB A I V RRB FB B II IOUT R B R A00 0= − DC-DC CONVERTER FB OUT SDA SCL OUT0 GND RFS0 = 80kΩ 4.7kΩ4.7kΩ VCC VCC VOUT = 2.0V* FS0 R0B = 2.67kΩ R0A = 4kΩ VFB = 0.8V* IR0A IR0B IOUT0 DS4432 *VOUT AND VFB VALUES ARE DETERMINED BY THE DC-DC CONVERTER AND SHOULD NOT BE CONFUSED WITH VOUT AND VRFS OF THE DS4432. Figure 3. Example Application Circuit PACKAGE TYPE PACKAGE CODE DOCUMENT NO.

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