DAC6571 www.ti.com SLAS406B – DECEMBER 2003 – REVISED AUGUST 2005 +2.7 V to +5.5 V, I2C INTERFACE, VOLTAGE OUTPUT, 10-BIT DIGITAL-TO-ANALOG CONVERTER FEATURES DESCRIPTION • • • • • • • The DAC6571 is a low-power, single-channel, 10-bit buffered voltage output digital-to-analog converter (DAC). Its on-chip precision output amplifier allows rail-to-rail output swing to be achieved. The DAC6571 utilizes an I2C-compatible, two-wire serial interface that operates at clock rates up to 3.4 MBPS with address support of up to two DAC6571s on the same data bus. • • • • Micropower Operation: 125 µA @ 3 V Fast Update Rate: 188 kSPS Power-On Reset to Zero +2.7-V to +5.5-V Power Supply Specified Monotonic by Design I2C™ Interface up to 3.4 MBPS On-Chip Output Buffer Amplifier, Rail-to-Rail Operation Double-Buffered Input Register Address Support for up to Two DAC6571s Small SOT23-6 Package Operation From –40°C to +105°C The output voltage range of the DAC is 0 V to VDD. The DAC6571 incorporates a power-on-reset circuit that ensures that the DAC output powers up at zero volts and remains there until a valid write to the device takes place. The DAC6571 contains a power-down feature, accessed via the internal control register, that reduces the current consumption of the device to 50 nA at 5 V. APPLICATIONS • • • • • Process Control Data Acquistion Systems Closed-Loop Servo Control PC Peripherals Portable Instrumentation The low power consumption of this part in normal operation makes it ideally suited for portable battery operated equipment. The power consumption is less than 0.7 mW at VDD = 5 V reducing to 1 µW in power-down mode. The DAC7571/6571/5571 are 12/10/8-bit, single-channel I2C DACs from the same family. The DAC7574/6574/5574 and DAC7573/6573/5573 are 12/10/8-bit, quad-channel I2C DACs. Also see the DAC8571/8574 for single/quad-channel, 16-bit I2C DACs. VDD GND Power-On Reset Ref (+) Ref (−) 10-Bit DAC DAC Register I2C Control Logic A0 SCL Output Buffer Power-Down Control Logic VOUT Resistor Network SDA Please be aware that an important notice concerning availability, standard warranty, and use in critical applications of Texas Instruments semiconductor products and disclaimers thereto appears at the end of this data sheet. I2C is a trademark of Philips Corporation. PRODUCTION DATA information is current as of publication date. Products conform to specifications per the terms of the Texas Instruments standard warranty. Production processing does not necessarily include testing of all parameters. Copyright © 2003–2005, Texas Instruments Incorporated DAC6571 www.ti.com SLAS406B – DECEMBER 2003 – REVISED AUGUST 2005 This integrated circuit can be damaged by ESD. Texas Instruments recommends that all integrated circuits be handled with appropriate precautions. Failure to observe proper handling and installation procedures can cause damage. ESD damage can range from subtle performance degradation to complete device failure. Precision integrated circuits may be more susceptible to damage because very small parametric changes could cause the device not to meet its published specifications. PACKAGE/ORDERING INFORMATION (1) PRODUCT PACKAGE PACKAGE DESIGNATOR SPECIFIED TEMPERATURE RANGE PACKAGE MARKING DAC6571 SOT23-6 DBV – 40°C to +105°C D671 (1) ORDERING NUMBER TRANSPORT MEDIA DAC6571IDBVT 250 Piece Small Tape and Reel DAC6571IDBVR 3000 Piece Tape and Reel For the most current package and ordering information see the Package Option Addendum at the end of this datasheet, or see the TI web site at www.ti.com. PIN CONFIGURATIONS (TOP VIEW) 1 2 3 D671 VOUT GND VDD 6 PIN DESCRIPTION (SOT23-6) A0 SCL SDA PIN NAME 1 VOUT Analog output voltage from DAC 2 GND Ground reference point for all circuitry on the part 3 VDD Analog Voltage Supply Input 4 SDA Serial Data Input 5 SCL Serial Clock Input 1 6 A0 2 LOT TRACE CODE: 5 4 (BOTTOM VIEW) 5 4 YMLL 6 3 DESCRIPTION Device Address Select Year (3 = 2003); M onth (1–9 = JAN–SEP; A = OCT, B = NOV, C = DEC); LL — Random code generated when assembly is requested. Lot Trace Code ABSOLUTE MAXIMUM RATINGS (1) UNITS VDD to GND –0.3 V to +6 V Digital input voltage to GND –0.3 V to +VDD + 0.3 V VOUT to GND –0.3 V to +VDD + 0.3 V Operating temperature range –40°C to + 105°C Storage temperature range –65°C to + 150°C Junction temperature range (TJ max) +150°C Power dissipation (TJ max – TA)RθJA Thermal impedance, RθJA Lead temperature, soldering (1) 2 240°C/W Vapor phase (60s) 215°C Infrared (15s) 220°C Stresses above those listed under Absolute Maximum Ratings may cause permanent damage to the device. Exposure to absolute maximum conditions for extended periods may affect device reliability. DAC6571 www.ti.com SLAS406B – DECEMBER 2003 – REVISED AUGUST 2005 ELECTRICAL CHARACTERISTICS VDD = +2.7 V to +5.5 V; RL = 2 kΩ to GND; CL = 200 pF to GND; all specifications –40°C to +105°C unless otherwise noted. PARAMETER DAC6571 CONDITIONS MIN TYP MAX UNITS STATIC PERFORMANCE (1) Resolution 10 Bits Relative accuracy Differential nonlinearity Assured monotonic by design Zero code error Full-scale error All ones loaded to DAC register ±2 LSB ±0.5 LSB 5 20 mV –0.15 –1.25 % of FSR ± 1.25 % of FSR Gain error Zero code error drift ±7 µV/°C Gain temperature coefficient ±3 ppm of FSR/°C OUTPUT CHARACTERISTICS (2) Output voltage range Output voltage settling time 0 1/4 Scale to 3/4 scale change (400H to C00H) ; RL = ∞ 7 Slew rate Capacitive load stability Code change glitch impulse 9 µs 1 V/µs pF RL = ∞ 470 1000 pF 1 LSB Change around major carry 20 nV – s 0.5 nV – s 1 Ω VDD = +5 V 50 mA VDD = +3 V 20 mA Coming out of power-down mode, VDD = +5 V 2.5 µs Coming out of power-down mode, VDD = +3 V 5 µs DC output impedance Power-up time V RL = 2 kΩ Digital feedthrough Short-circuit current VDD LOGIC INPUTS (2) Input current VINL, Input low voltage VDD = +3 V VINH, Input high voltage VDD = +5 V ±1 µA 0.3 × VDD V 3 pF 5.5 V 0.7 × VDD V Pin capacitance POWER REQUIREMENTS VDD 2.7 IDD (normal operation) DAC active and excluding load current VDD = +3.6 V to +5.5 V VIH = VDD and VIL = GND 155 200 µA VDD = +2.7 V to +3.6 V VIH = VDD and VIL = GND 125 160 µA IDD (all power-down modes) VDD = +3.6 V to +5.5 V VIH = VDD and VIL = GND 0.2 1 µA VDD = +2.7 V to +3.6 V VIH = VDD and VIL = GND 0.05 1 µA ILOAD = 2 mA, VDD = +5 V 93 POWER EFFICIENCY IOUT/IDD (1) (2) % Linearity calculated using a reduced code range of 12 to 1012; output unloaded. Specified by design and characterization; not production tested. 3 DAC6571 www.ti.com SLAS406B – DECEMBER 2003 – REVISED AUGUST 2005 TIMING CHARACTERISTICS SYMBOL PARAMETER TEST CONDITIONS fSCL SCL Clock Frequency MIN MAX UNITS Standard mode 100 kHz Fast mode 400 kHz High-speed mode, CB – 100 pF max 3.4 MHz 1.7 MHz High-Speed mode, CB – 400 pF max tBUF tHD; tSTA tLOW tHIGH tSU; tSTA tSU; tDAT tHD; tDAT tRCL Bus Free Time Between a STOP and START Condition Standard mode 4.7 µs Fast mode 1.3 µs Hold Time (Repeated) START Condition Standard mode 4.0 µs Fast mode 600 ns High-speed mode 160 ns Standard mode 4.7 µs LOW Period of the SCL Clock HIGH Period of the SCL Clock Setup Time for a Repeated START Condition Data Setup Time Data Hold Time Rise Time of SCL Signal Fast mode 1.3 µs High-speed mode, CB – 100 pF max 160 ns High-speed mode, CB – 400 pF max 320 ns Standard mode 4.0 µs Fast mode 600 ns High-speed mode, CB – 100 pF max 60 ns High-speed mode, CB – 400 pF max 120 ns Standard mode 4.7 µs Fast mode 600 ns High-speed mode 160 ns Standard mode 250 ns Fast mode 100 ns High-speed mode 10 ns Standard mode 0 3.45 µs Fast mode 0 0.9 µs High-speed mode, CB – 100 pF max 0 70 ns High-speed mode, CB – 400 pF max 0 150 ns 1000 ns 20 + 0.1CB 300 ns High-speed mode, CB – 100 pF max 10 40 ns High-speed mode, CB – 400 pF max 20 Standard mode Fast mode tRCL1 tFCL Rise Time of SCL Signal After a Repeated START Condition and After an Acknowledge BIT Fall Time of SCL Signal Standard mode Fast mode Rise Time of SDA Signal Fall Time of SDA Signal ns 300 ns 10 80 ns 20 160 ns 300 ns Standard mode 20 + 0.1CB 300 ns High-speed mode, CB – 100 pF max 10 40 ns High-speed mode, CB – 400 pF max 20 80 ns 1000 ns Standard mode 20 + 0.1CB 300 ns High-speed mode, CB – 100 pF max 10 80 ns High-speed mode, CB – 400 pF max 20 160 ns Standard mode 300 ns 20 + 0.1CB 300 ns High-speed mode, CB – 100 pF max 10 80 ns High-speed mode, CB – 400 pF max 20 160 ns Fast mode 4 ns High-speed mode, CB – 400 pF max Fast mode tFDA 20 + 0.1CB 80 1000 High-speed mode, CB – 100 pF max Fast mode tRDA TYP DAC6571 www.ti.com SLAS406B – DECEMBER 2003 – REVISED AUGUST 2005 TIMING CHARACTERISTICS (continued) SYMBOL PARAMETER TEST CONDITIONS tSU; tSTO Setup Time for STOP Condition Standard mode 4.0 µs Fast mode 600 ns High-speed mode 160 ns CB Capacitive Load for SDA and SCL tSP Pulse Width of Spike Suppressed VNH Noise Margin at the HIGH Level for Each Connected Device (Including Hysteresis) MIN TYP MAX UNITS 400 pF Fast mode 50 ns High-speed mode 10 ns Standard mode 0.2 VDD V 0.1 VDD V Fast mode High-speed mode VNL Noise Margin at the LOW Level for Each Connected Device (Including Hysteresis) Standard mode Fast mode High-speed mode TYPICAL CHARACTERISTICS: VDD = +5 V At TA = +25°C, +VDD = +5 V, unless otherwise noted. LINEARITY ERROR AND DIFFERENTIAL LINEARITY ERROR vs CODE (–40°C) LINEARITY ERROR AND DIFFERENTIAL LINEARITY ERROR vs CODE (+25°C ) 2 VDD = 5 V at −40°C LE − LSB 1 0 −1 −2 0 −0.25 0.25 0 −0.25 −0.5 0 128 256 384 512 640 Digital Input Code 768 896 1024 0 128 256 384 512 640 Digital Input Code 768 896 Figure 1. Figure 2. LINEARITY ERROR AND DIFFERENTIAL LINEARITY ERROR vs CODE (+105°C) TYPICAL TOTAL UNADJUSTED ERROR 2 1024 16 VDD = 5 V, TA = 25°C VDD = 5 V at 105°C 1 0 8 Output Error (mV) LE − LSB −1 0.5 −0.5 −1 −2 0.5 DLE − LSB 0 0.5 0.25 VDD = 5 V at 25°C 1 −2 DLE − LSB DLE − LSB LE − LSB 2 0.25 0 −8 0 −0.25 −0.5 0 128 256 384 512 640 Digital Input Code Figure 3. 768 896 1024 −16 0 128 256 384 512 640 Digital Input Code 768 896 1024 Figure 4. 5 DAC6571 www.ti.com SLAS406B – DECEMBER 2003 – REVISED AUGUST 2005 TYPICAL CHARACTERISTICS: VDD = +5 V (continued) At TA = +25°C, +VDD = +5 V, unless otherwise noted. ZERO-SCALE ERROR vs TEMPERATURE FULL-SCALE ERROR vs TEMPERATURE 30 30 VDD = 5 V VDD = 5 V 20 Full-Scale Error − mV Zero-Scale Error − mV 20 10 0 −10 −20 10 0 −10 −20 −30 −50 −40 −30 −20 −10 0 −30 −50 −40 −30 −20 −10 0 10 20 30 40 50 60 70 80 90 100 110 10 20 30 40 50 60 70 80 90 100 110 T − Temperature − C T − Temperature − C Figure 5. Figure 6. IDD HISTOGRAM SOURCE AND SINK CURRENT CAPABILITY 2500 5 VDD = 5 V DAC Loaded with 3FF 4 1500 V O U T (V) f − Frequency − Hz 2000 1000 500 H 3 2 1 DAC Loaded with 00 H 200 190 180 170 160 150 140 130 120 110 100 90 80 0 0 0 IDD − Supply Current − A 5 10 15 ISOURCE/SINK (mA) Figure 7. Figure 8. SUPPLY CURRENT vs CODE SUPPLY CURRENT vs TEMPERATURE 500 300 VDD = 5 V I DD − Supply Current − µ A I DD − Supply Current − µ A VDD = 5 V 400 300 200 100 0 0H BH 80H 100H 180H 200H 280H 300H 380H 3F3H 3FFH Code Figure 9. 6 250 200 150 100 50 0 −50 −40 −30 −20 −10 0 10 20 30 40 50 60 70 80 90 100 110 T − Temperature − C Figure 10. DAC6571 www.ti.com SLAS406B – DECEMBER 2003 – REVISED AUGUST 2005 TYPICAL CHARACTERISTICS: VDD = +5 V (continued) At TA = +25°C, +VDD = +5 V, unless otherwise noted. SUPPLY CURRENT vs SUPPLY VOLTAGE POWER-DOWN CURRENT vs SUPPLY VOLTAGE 300 90 80 200 70 150 IDD (nA) I DD − Supply Current − µ A 100 250 100 60 +105°C 50 –40°C 40 30 50 20 0 2.7 3.2 3.7 4.2 4.7 VDD − Supply Voltage − V 5.2 5.7 +25°C 10 0 2.7 3.2 3.7 4.2 4.7 5.2 5.7 VDD (V) Figure 11. Figure 12. SUPPLY CURRENT vs LOGIC INPUT VOLTAGE FULL-SCALE SETTLING TIME CLK (5V/div) 2500 IDD (µA) 2000 VOUT (1V/div) 1500 1000 Full−Scale Code Change 00H to 3FF H Output Loaded with 2 KΩ and 200pF to GND 500 0 Time (1µs/div) 0 1 2 3 4 5 VLOGIC (V) Figure 13. Figure 14. 7 DAC6571 www.ti.com SLAS406B – DECEMBER 2003 – REVISED AUGUST 2005 TYPICAL CHARACTERISTICS: VDD = +5 V (continued) At TA = +25°C, +VDD = +5 V, unless otherwise noted. FULL-SCALE SETTLING TIME HALF-SCALE SETTLING TIME CLK (5V/div) CLK (5V/div) VOUT (1V/div) Full−Scale Code Change 1023 to 0 Output Loaded with 2 k and 200 pF to GND Half−Scale Code Change 256 to 768 Output Loaded with 2kΩ and 200pF to GND VOUT (1V/div) Time 1 s/div Time (1µs/div) Figure 15. Figure 16. HALF-SCALE SETTLING TIME POWER-ON RESET TO 0 V C LK (5 V/div) H alf−S ca le C o de C ha nge Loaded with 2kΩ to VDD. 768 to 256 O utpu t Lo ad ed w ith 2kΩ an d 20 0pF to G N D VDD (1V/div) V O U T (1V /div) VOUT (1V/div) Time (1µs /d iv) Time (20µs/div) Figure 17. Figure 18. EXITING POWER DOWN (512 Loaded) CODE CHANGE GLITCH Loa ded w ith 2 kΩ and 2 00p F to G N D . C ode C hang e: 512 to 511 VOUT (20mV/div) CLK (5V/div) VOUT (1V/div) Time (0.5 µs/div) Time (5µs/div) Figure 19. 8 Figure 20. DAC6571 www.ti.com SLAS406B – DECEMBER 2003 – REVISED AUGUST 2005 TYPICAL CHARACTERISTICS: VDD = +2.7 V At TA = +25°C, +VDD = +2.7 V, unless otherwise noted. LINEARITY ERROR AND DIFFERENTIAL LINEARITY ERROR vs CODE (–40°C) LINEARITY ERROR AND DIFFERENTIAL LINEARITY ERROR vs CODE (+25°C) 2 VDD = 2.7 V at 25°C 1 LE − LSB LE − LSB 0 −1 0 −1 −2 −2 0.5 0.5 DLE − LSB DLE − LSB 2 VDD = 2.7 V at −40°C 1 0.25 0 −0.25 0.25 0 −0.25 −0.5 −0.5 0 128 256 384 512 640 768 896 0 1024 128 256 640 Figure 22. LINEARITY ERROR AND DIFFERENTIAL LINEARITY ERROR vs CODE (+105°C) OUTPUT ERROR vs CODE (+25°C) 768 896 1024 16 VDD = 2.7 V at 105°C 1 VDD = 2.7 V, TA = 25°C 0 8 −1 Output Error (mV) LE − LSB 512 Figure 21. 2 −2 0.5 DLE − LSB 384 Digital Input Code Digital Input Code 0.25 0 0 −8 −0.25 −0.5 0 128 256 384 512 640 768 896 1024 −16 0 Digital Input Code 256 384 512 640 768 896 1024 Digital Input Code Figure 23. Figure 24. ZERO-SCALE ERROR vs TEMPERATURE FULL-SCALE ERROR vs TEMPERATURE 30 30 VDD = 2.7 V VDD = 2.7 V 20 20 Full-Scale Error − mV Zero-Scale Erro − mV 128 10 0 −10 −20 −30 −50 −40 −30 −20 −10 0 10 0 −10 −20 −30 10 20 30 40 50 60 70 80 90 100 110 T − Temperature − C Figure 25. −50 −40−30 −20 −10 0 10 20 30 40 50 60 70 80 90 100 110 T − Temperature − C Figure 26. 9 DAC6571 www.ti.com SLAS406B – DECEMBER 2003 – REVISED AUGUST 2005 TYPICAL CHARACTERISTICS: VDD = +2.7 V (continued) At TA = +25°C, +VDD = +2.7 V, unless otherwise noted. IDD HISTOGRAM SOURCE AND SINK CURRENT CAPABILITY 3 2500 VDD = 2.7 V V D D = + 3V D AC Lo ad ed w ith 3FFH 2 1500 VOUT (V) f − Frequency − Hz 2000 1000 1 500 200 190 180 170 160 150 140 130 110 120 90 80 0 100 D AC Lo ade d w ith 000 H 0 IDD − Supply Current − A 0 5 10 15 I S O U R C E /S IN K (m A) Figure 27. Figure 28. SUPPLY CURRENT vs CODE SUPPLY CURRENT vs TEMPERATURE 500 300 VDD = 2.7 V 250 400 I DD − Supply Current − µ A I DD − Supply Current − µ A VDD = 2.7 V 300 200 100 0 0H BH 80H 100H 180H 200H 280H 300H 380H 3F3H 3FFH 200 150 100 50 0 −50 −40 −30 −20 −10 0 Code 10 20 30 40 50 60 70 80 90 100 110 T − Temperature − C Figure 29. Figure 30. SUPPLY CURRENT vs LOGIC INPUT VOLTAGE FULL-SCALE SETTLING TIME 2500 C LK (2.7V /div) IDD (µA) 2000 1500 1000 F ull−S c ale C o de C h an ge 000 H to 3 FF H O utpu t L oad ed w ith 500 V O U T (1V /div ) 0 2 kΩ an d 200 pF to G N D Tim e (1 µ s/d iv ) 0 1 2 3 4 5 VLOGIC (V) Figure 31. 10 Figure 32. DAC6571 www.ti.com SLAS406B – DECEMBER 2003 – REVISED AUGUST 2005 TYPICAL CHARACTERISTICS: VDD = +2.7 V (continued) At TA = +25°C, +VDD = +2.7 V, unless otherwise noted. FULL-SCALE SETTLING TIME HALF-SCALE SETTLING TIME CLK (2.7V/div) CLK (2.7V/div) Full−Scale Code Change 3FFH to 000H Output Loaded with 2kΩ and 200pF to GND VOUT (1V/div) Half−Scale Code Change 256 to 768 VOUT (1V/div) Output Loaded with 2 kΩ and 200 pF to GND Time (1 µs/div) Time (1µs/div) Figure 33. Figure 34. HALF-SCALE SETTLING TIME POWER-ON RESET 0 V POWER-ON RESET to 0V C LK (2.7V /div) H alf−Sca le C ode C ha nge 768 to 256 O u tp ut Lo aded w ith 2 kΩ and 200 pF to GND V O U T (1V/d iv) Time (1 µs/div) Time (20µs/div) Figure 35. Figure 36. EXITING POWER DOWN (512 Loaded) CODE CHANGE GLITCH H Loa de d w ith 2k and 2 00pF to G N D . CLK (2.7V/div) C ode C hange : VOUT (1V/div) Time (5µs/div) Figure 37. VOUT (20mV/div) 512 to 511 Time (0.5 µs/div) Figure 38. 11 DAC6571 www.ti.com SLAS406B – DECEMBER 2003 – REVISED AUGUST 2005 THEORY OF OPERATION D/A SECTION The architecture of the DAC6571 consists of a string DAC followed by an output buffer amplifier. Figure 39 shows a generalized block diagram of the DAC architecture. VDD 50 k 50 k 70 k _ Ref+ Resistor String Ref− DAC Register + VOUT GND Figure 39. R-String DAC Architecture The input coding to the DAC6571 is unsigned binary, which gives the ideal output voltage as: V OUT VDD D 1024 Where D = decimal equivalent of the binary code that is loaded to the DAC register; it can range from 0 to 1023. RESISTOR STRING The resistor string section is shown in Figure 40. It is basically a divide-by-2 resistor, followed by a string of resistors, each of value R. The code loaded into the DAC register determines at which node on the string the voltage is tapped off to be fed into the output amplifier by closing one of the switches connecting the string to the amplifier. Because the architecture consists of a string of resistors, it is specified monotonic. To Output Amplifier VDD GND R R R R Figure 40. Typical Resistor String Output Amplifier The output buffer amplifier is a gain-of-2 amplifier, capable of generating rail-to-rail voltages on its output, which gives an output range of 0 V to VDD. It is capable of driving a load of 2 kΩ in parallel with 1000 pF to GND. The source and sink capabilities of the output amplifier can be seen in the typical characteristics curves. The slew rate is 1 V/µs with a half-scale settling time of 7 µs with the output unloaded. I2C Interface I2C is a two-wire serial interface developed by Philips Semiconductor (see I2C-Bus Specification, Version 2.1, January 2000). The bus consists of a data line (SDA) and a clock line (SCL) with pull-up structures. When the bus is idle, both SDA and SCL lines are pulled high. All the I2C-compatible devices connect to the I2C bus through open drain I/O pins, SDA and SCL. A master device, usually a microcontroller or a digital signal processor, controls the bus. The master is responsible for generating the SCL signal and device addresses. The master also generates specific conditions that indicate the START and STOP of data transfer. A slave device receives and/or transmits data on the bus under control of the master device. The DAC6571 works as a slave and supports the following data transfer modes, as defined in the I2C-Bus 12 DAC6571 www.ti.com SLAS406B – DECEMBER 2003 – REVISED AUGUST 2005 THEORY OF OPERATION (continued) Specification: standard mode (100 kBPS), fast mode (400 kBPS), and high-speed mode (3.4 MBPS). The data transfer protocol for standard and fast modes is exactly the same; therefore, they are referred to as F/S-mode in this document. The protocol for high-speed mode is different from the F/S-mode, and it is referred to as HS-mode. The DAC6571 supports 7-bit addressing; 10-bit addressing and general call address are not supported. F/S-Mode Protocol • • • • The master initiates data transfer by generating a start condition. A start condition is initiated when a high-to-low transition occurs on the SDA line while SCL is high, as shown in Figure 41. All I2C-compatible devices should recognize a start condition. The master then generates the SCL pulses and transmits the 7-bit address and the read/write direction bit R/W on the SDA line. During all transmissions, the master ensures that data is valid. A valid data condition requires the SDA line to be stable during the entire high period of the clock pulse (see Figure 42). All devices recognize the address sent by the master and compare it to their internal fixed addresses. Only the slave device with a matching address generates an acknowledge (see Figure 43) by pulling the SDA line low during the entire high period of the ninth SCL cycle. On detecting this acknowledge, the master knows that a communication link with a slave has been established. The master generates further SCL cycles to either transmit data to the slave (R/W bit 1) or receive data from the slave (R/W bit 0). In either case, the receiver needs to acknowledge the data sent by the transmitter. Therefore, an acknowledge signal can either be generated by the master or by the slave, depending on which one is the receiver. The 9-bit valid data sequences, consisting of 8-bit data and 1-bit acknowledge, can continue as long as necessary. To signal the end of the data transfer, the master generates a stop condition by pulling the SDA line from low to high while the SCL line is high (see Figure 41). This releases the bus and stops the communication link with the addressed slave. All I2C-compatible devices must recognize the stop condition. On the receipt of a stop condition, all devices know that the bus is released, and they wait for a start condition followed by a matching address. HS-Mode Protocol • • • When the bus is idle, both SDA and SCL lines are pulled high by the pull-up devices. The master generates a start condition followed by a valid serial byte containing HS master code 00001XXX. This transmission is made in F/S-mode at no more than 400 kBPS. No device is allowed to acknowledge the HS master code, but all devices must recognize it and switch their internal setting to support 3.4 MBPS operation. The master then generates a repeated start condition (a repeated start condition has the same timing as the start condition). After this repeated start condition, the protocol is the same as F/S-mode, except that transmission speeds up to 3.4 MBPS are allowed. A stop condition ends the HS-mode and switches all the internal settings of the slave devices to support the F/S-mode. Instead of using a stop condition, repeated start conditions should be used to secure the bus in HS-mode. SDA SDA SCL SCL S P Start Condition Stop Condition Figure 41. START and STOP Conditions 13 DAC6571 www.ti.com SLAS406B – DECEMBER 2003 – REVISED AUGUST 2005 THEORY OF OPERATION (continued) SDA SCL Data Line Stable; Data Valid Change of Data Allowed Figure 42. Bit Transfer on the I2C Bus Data Output by Transmitter Not Acknowledge Data Output by Receiver Acknowledge SCL From Master 1 2 8 9 S Clock Pulse for Acknowledgement START Condition Figure 43. Acknowledge on the I2C Bus Recognize START or REPEATED START Condition Recognize STOP or REPEATED START Condition Generate ACKNOWLEDGE Signal P SDA MSB Acknowledgement Signal From Slave Sr Address R/W SCL S or Sr START or Repeated START Condition 1 2 7 8 9 ACK 1 3-8 9 ACK Sr or P Clock Line Held Low While Interrupts are Serviced STOP or Repeated START Condition Figure 44. Bus Protocol 14 2 DAC6571 www.ti.com SLAS406B – DECEMBER 2003 – REVISED AUGUST 2005 THEORY OF OPERATION (continued) DAC6571 I2C Update Sequence The DAC6571 requires a start condition, a valid I2C address, a control-MSB byte, and an LSB byte for a single update. After the receipt of each byte, the DAC6571 acknowledges by pulling the SDA line low during the high period of a single clock pulse. A valid I2C address selects the DAC6571. The CTRL/MSB byte sets the operational mode of the DAC6571, and the four most significant bits. The DAC6571 then receives the LSB byte containing six least significant data bits. The DAC6571 performs an update on the falling edge of the acknowledge signal that follows the LSB byte. For the first update, the DAC6571 requires a start condition, a valid I2C address, a CTRL/MSB byte, and an LSB byte. For all consecutive updates, the device needs a CTRL/MSB byte, and an LSB byte. Using the I2C high-speed mode (fscl = 3.4 MHz), with the clock running at 3.4 MHz, each 10-bit DAC update other than the first update can be done within 18 clock cycles (CTRL/MSB byte, acknowledge signal, LSB byte, acknowledge signal), at 188.88 kSPS. Using the fast mode (fscl = 400 kHz), and the clock running at 400 kHz, the maximum DAC update rate is limited to 22.22 kSPS. Once a stop condition is received, DAC6571 releases the I2C bus and awaits a new start condition. Address Byte MSB 1 LSB 0 0 1 1 0 A0 0 The address byte is the first byte received following the START condition from the master device. The first six bits (MSBs) of the address are factory-preset to 100110. The next bit of the address is the device select bit A0. The A0 address input can be connected to VDD or digital GND, or can be actively driven by TTL/CMOS logic levels. The device address is set by the state of this pin during the power-up sequence of the DAC6571. Up to two devices (DAC6571) can be connected to the same I2C-bus without requiring additional glue logic. Broadcast Address Byte MSB 1 LSB 0 0 1 0 0 0 0 Broadcast addressing is also supported by DAC6571. Broadcast addressing can be used for synchronously updating or powering down multiple DAC6571 devices. Using the broadcast address, DAC6571 responds regardless of the state of the address pin A0. Control - Most Significant Byte The most significant byte (CTRL/MSB[7:0]) consists of two zeros, two power-down bits, and four most significant bits of 10-bit unsigned binary D/A conversion data. Least Significant Byte The least significant byte (LSB[7:0]) consists of the six least significant bits of the 10-bit unsigned binary D/A conversion data, followed by two don't care bits. DAC6571 updates at the falling edge of the acknowledge signal that follows the LSB[0] bit. 15 DAC6571 www.ti.com SLAS406B – DECEMBER 2003 – REVISED AUGUST 2005 Standard- and Fast-Mode: S SLAVE ADDRESS 0 A Ctrl/MS-Byte A LS-Byte A/A P Data Transferred (n* Words + Acknowledge) Word = 16 Bit ”0” (write) From Master to DAC6571 DAC6571 I2C-SLAVE ADDRESS: From DAC6571 to Master MSB A = A = S = Sr = P = LSB 1 Acknowledge (SDA LOW) Not Acknowledge (SDA HIGH) START Condition Repeated START Condition STOP Condition 0 0 1 1 0 A0 0 Factory Preset A0 = I2C Address Pin High-Speed Mode (HS Mode): F/S Mode S HS Mode HS-Master Code A Sr Slave Address 0 A Ctrl/MS-Byte HS-Mode Master Code: A/A P HS Mode Continues Sr Slave Address MSB LSB 0 0 0 1 X X 0 Ctrl/MS-Byte: LS-Byte: MSB 0 A LS-Byte Data Transferred (n* Words + Acknowledge) Word = 16 Bit ”0” (write) 0 F/S Mode 0 PD1 PD0 D9 D8 D7 LSB MSB D6 D5 LSB D4 D3 D2 D1 D0 X X D9 − D0 = Data Bits Figure 45. Master Transmitter Addressing DAC6571 as a Slave Receiver With a 7-Bit Address 16 DAC6571 www.ti.com SLAS406B – DECEMBER 2003 – REVISED AUGUST 2005 POWER-ON RESET The DAC6571 contains a power-on reset circuit that controls the output voltage during power up. On power up, the DAC register is filled with zeros and the output voltage is 0 V. It remains at a zero-code output until a valid write sequence is made to the DAC. This configuration is useful in applications where it is important to know the state of the DAC output while it is in the process of powering up. POWER-DOWN MODES The DAC6571 contains four separate modes of operation. These modes are programmable via two bits (PD1 and PD0). Table 1 shows how the state of these bits correspond to the mode of operation. Table 1. Modes of Operation for the DAC6571 PD1 PD0 0 0 OPERATING MODE Normal Operation 0 1 1 kΩ to AGND, PWD 1 0 100 kΩ to AGND, PWD 1 1 High Impedance, PWD When both bits are set to zero, the device works normally with normal power consumption of 150 µA at 5 V. However, for the three power-down modes, the supply current falls to 200 nA at 5 V (50 nA at 3 V). Not only does the supply current fall, but the output stage is also internally switched from the output of the amplifier to a resistor network of known values. This has the advantage that the output impedance of the device is known while in power-down mode. There are three different options: The output is connected internally to AGND through a 1-kΩ resistor, a 100-kΩ resistor, or it is left open-circuited (high impedance). The output stage is illustrated in Figure 46. Amplifier Resistor String DAC VOUT Power-Down Circuitry Resistor Network Figure 46. Output Stage During Power Down All linear circuitry is shut down when the power-down mode is activated. However, the contents of the DAC register are unaffected when in power-down. The time required to exit power down is typically 2.5 µs for AVDD = 5 V and 5 µs for AVDD = 3 V. See the Typical Characteristics section for more information. CURRENT CONSUMPTION The DAC6571 typically consumes 150 µA at VDD = 5 V and 120 µA at VDD = 3 V. Additional current consumption can occur due to the digital inputs if VIH << VDD. For the most efficient power operation, CMOS logic levels are recommended at the digital inputs to the DAC. In power-down mode, typical current consumption is 200 nA. DRIVING RESISTIVE AND CAPACITIVE LOADS The DAC6571 output stage is capable of driving loads of up to 1000 pF while remaining stable. Within the offset and gain error margins, the DAC6571 can operate rail-to-rail when driving a capacitive load. When the outputs of the DAC are driven to the positive rail under resistive loading, the PMOS transistor of each Class-AB output stage can enter into the linear region. When this occurs, the added IR voltage drop deteriorates the linearity performance of the DAC. This degradation may occur approximately within the top 20 mV of the DAC digital input-to-voltage output transfer characteristic. 17 DAC6571 www.ti.com SLAS406B – DECEMBER 2003 – REVISED AUGUST 2005 OUTPUT VOLTAGE STABILITY The DAC6571 exhibits excellent temperature stability of 5 ppm/°C typical output voltage drift over the specified temperature range of the device. This enables the output voltage to stay within a ±25–µV window for a ±1°C ambient temperature change. Combined with good dc noise performance and true 10-bit differential linearity, the DAC6571 becomes a perfect choice for closed-loop control applications. APPLICATIONS USING REF02 AS A POWER SUPPLY FOR THE DAC6571 Due to the extremely low supply current required by the DAC6571, a possible configuration is to use a REF02 +5-V precision voltage reference to supply the required voltage to the DAC6571 supply input as well as the reference input, as shown in Figure 47. This is especially useful if the power supply is quite noisy or if the system supply voltages are at some value other than 5 V. The REF02 outputs a steady supply voltage for the DAC6571. If the REF02 is used, the current it needs to supply to the DAC6571 is 140 µA typical. When a DAC output is loaded, the REF02 also needs to supply the current to the load. The total typical current required (with a 5-mW load on a given DAC output) is: 140 µA + (5 mW/5 V) = 1.14 mA. The load regulation of the REF02 is typically (0.005% × VDD)/mA, which results in an error of 0.285 mV for the 1.14-mA current drawn from it. This corresponds to a 0.05 LSB error for a 0-V to 5-V output range. 15 V REF02 5V 1.14 mA I2C Interface A0 SCL DAC6571 VOUT = 0 V to 5 V SDA Figure 47. REF02 as Power Supply to DAC6571 LAYOUT A precision analog component requires careful layout, adequate bypassing, and clean, well-regulated power supplies. The power applied to VDD should be well-regulated and low-noise. Switching power supplies and dc/dc converters often have high-frequency glitches or spikes riding on the output voltage. In addition, digital components can create similar high-frequency spikes as their internal logic switches states. This noise can easily couple into the DAC output voltage through various paths between the power connections and analog output. As with the GND connection, VDD should be connected to a +5-V power supply plane or trace that is separate from the connection for digital logic until they are connected at the power entry point. In addition, the 1-µF to 10-µF and 0.1-µF bypass capacitors are strongly recommended. In some situations, additional bypassing may be required, such as a 100-µF electrolytic capacitor or even a Pi filter made up of inductors and capacitors—all designed to essentially low-pass filter the +5-V supply, removing the high-frequency noise. 18 PACKAGE OPTION ADDENDUM www.ti.com 11-Apr-2013 PACKAGING INFORMATION Orderable Device Status (1) Package Type Package Pins Package Drawing Qty Eco Plan Lead/Ball Finish (2) MSL Peak Temp Op Temp (°C) Top-Side Markings (3) (4) DAC6571IDBVR ACTIVE SOT-23 DBV 6 3000 Green (RoHS & no Sb/Br) CU NIPDAU Level-1-260C-UNLIM -40 to 105 D671 DAC6571IDBVRG4 ACTIVE SOT-23 DBV 6 3000 Green (RoHS & no Sb/Br) CU NIPDAU Level-1-260C-UNLIM -40 to 105 D671 DAC6571IDBVT ACTIVE SOT-23 DBV 6 250 Green (RoHS & no Sb/Br) CU NIPDAU Level-1-260C-UNLIM -40 to 105 D671 DAC6571IDBVTG4 ACTIVE SOT-23 DBV 6 250 Green (RoHS & no Sb/Br) CU NIPDAU Level-1-260C-UNLIM -40 to 105 D671 (1) The marketing status values are defined as follows: ACTIVE: Product device recommended for new designs. LIFEBUY: TI has announced that the device will be discontinued, and a lifetime-buy period is in effect. NRND: Not recommended for new designs. Device is in production to support existing customers, but TI does not recommend using this part in a new design. PREVIEW: Device has been announced but is not in production. Samples may or may not be available. OBSOLETE: TI has discontinued the production of the device. (2) Eco Plan - The planned eco-friendly classification: Pb-Free (RoHS), Pb-Free (RoHS Exempt), or Green (RoHS & no Sb/Br) - please check http://www.ti.com/productcontent for the latest availability information and additional product content details. TBD: The Pb-Free/Green conversion plan has not been defined. Pb-Free (RoHS): TI's terms "Lead-Free" or "Pb-Free" mean semiconductor products that are compatible with the current RoHS requirements for all 6 substances, including the requirement that lead not exceed 0.1% by weight in homogeneous materials. Where designed to be soldered at high temperatures, TI Pb-Free products are suitable for use in specified lead-free processes. Pb-Free (RoHS Exempt): This component has a RoHS exemption for either 1) lead-based flip-chip solder bumps used between the die and package, or 2) lead-based die adhesive used between the die and leadframe. The component is otherwise considered Pb-Free (RoHS compatible) as defined above. Green (RoHS & no Sb/Br): TI defines "Green" to mean Pb-Free (RoHS compatible), and free of Bromine (Br) and Antimony (Sb) based flame retardants (Br or Sb do not exceed 0.1% by weight in homogeneous material) (3) MSL, Peak Temp. -- The Moisture Sensitivity Level rating according to the JEDEC industry standard classifications, and peak solder temperature. (4) Multiple Top-Side Markings will be inside parentheses. Only one Top-Side Marking contained in parentheses and separated by a "~" will appear on a device. If a line is indented then it is a continuation of the previous line and the two combined represent the entire Top-Side Marking for that device. Important Information and Disclaimer:The information provided on this page represents TI's knowledge and belief as of the date that it is provided. TI bases its knowledge and belief on information provided by third parties, and makes no representation or warranty as to the accuracy of such information. Efforts are underway to better integrate information from third parties. TI has taken and continues to take reasonable steps to provide representative and accurate information but may not have conducted destructive testing or chemical analysis on incoming materials and chemicals. TI and TI suppliers consider certain information to be proprietary, and thus CAS numbers and other limited information may not be available for release. In no event shall TI's liability arising out of such information exceed the total purchase price of the TI part(s) at issue in this document sold by TI to Customer on an annual basis. Addendum-Page 1 Samples PACKAGE OPTION ADDENDUM www.ti.com 11-Apr-2013 Addendum-Page 2 PACKAGE MATERIALS INFORMATION www.ti.com 8-Jul-2011 TAPE AND REEL INFORMATION *All dimensions are nominal Device Package Package Pins Type Drawing SPQ Reel Reel A0 Diameter Width (mm) (mm) W1 (mm) DAC6571IDBVR SOT-23 DBV 6 3000 178.0 9.0 DAC6571IDBVT SOT-23 DBV 6 250 178.0 9.0 Pack Materials-Page 1 B0 (mm) K0 (mm) P1 (mm) W Pin1 (mm) Quadrant 3.23 3.17 1.37 4.0 8.0 Q3 3.23 3.17 1.37 4.0 8.0 Q3 PACKAGE MATERIALS INFORMATION www.ti.com 8-Jul-2011 *All dimensions are nominal Device Package Type Package Drawing Pins SPQ Length (mm) Width (mm) Height (mm) DAC6571IDBVR SOT-23 DBV 6 3000 180.0 180.0 18.0 DAC6571IDBVT SOT-23 DBV 6 250 180.0 180.0 18.0 Pack Materials-Page 2 IMPORTANT NOTICE Texas Instruments Incorporated and its subsidiaries (TI) reserve the right to make corrections, enhancements, improvements and other changes to its semiconductor products and services per JESD46, latest issue, and to discontinue any product or service per JESD48, latest issue. Buyers should obtain the latest relevant information before placing orders and should verify that such information is current and complete. All semiconductor products (also referred to herein as “components”) are sold subject to TI’s terms and conditions of sale supplied at the time of order acknowledgment. TI warrants performance of its components to the specifications applicable at the time of sale, in accordance with the warranty in TI’s terms and conditions of sale of semiconductor products. Testing and other quality control techniques are used to the extent TI deems necessary to support this warranty. Except where mandated by applicable law, testing of all parameters of each component is not necessarily performed. TI assumes no liability for applications assistance or the design of Buyers’ products. Buyers are responsible for their products and applications using TI components. To minimize the risks associated with Buyers’ products and applications, Buyers should provide adequate design and operating safeguards. TI does not warrant or represent that any license, either express or implied, is granted under any patent right, copyright, mask work right, or other intellectual property right relating to any combination, machine, or process in which TI components or services are used. Information published by TI regarding third-party products or services does not constitute a license to use such products or services or a warranty or endorsement thereof. Use of such information may require a license from a third party under the patents or other intellectual property of the third party, or a license from TI under the patents or other intellectual property of TI. Reproduction of significant portions of TI information in TI data books or data sheets is permissible only if reproduction is without alteration and is accompanied by all associated warranties, conditions, limitations, and notices. TI is not responsible or liable for such altered documentation. Information of third parties may be subject to additional restrictions. Resale of TI components or services with statements different from or beyond the parameters stated by TI for that component or service voids all express and any implied warranties for the associated TI component or service and is an unfair and deceptive business practice. TI is not responsible or liable for any such statements. Buyer acknowledges and agrees that it is solely responsible for compliance with all legal, regulatory and safety-related requirements concerning its products, and any use of TI components in its applications, notwithstanding any applications-related information or support that may be provided by TI. Buyer represents and agrees that it has all the necessary expertise to create and implement safeguards which anticipate dangerous consequences of failures, monitor failures and their consequences, lessen the likelihood of failures that might cause harm and take appropriate remedial actions. Buyer will fully indemnify TI and its representatives against any damages arising out of the use of any TI components in safety-critical applications. In some cases, TI components may be promoted specifically to facilitate safety-related applications. With such components, TI’s goal is to help enable customers to design and create their own end-product solutions that meet applicable functional safety standards and requirements. Nonetheless, such components are subject to these terms. No TI components are authorized for use in FDA Class III (or similar life-critical medical equipment) unless authorized officers of the parties have executed a special agreement specifically governing such use. Only those TI components which TI has specifically designated as military grade or “enhanced plastic” are designed and intended for use in military/aerospace applications or environments. Buyer acknowledges and agrees that any military or aerospace use of TI components which have not been so designated is solely at the Buyer's risk, and that Buyer is solely responsible for compliance with all legal and regulatory requirements in connection with such use. TI has specifically designated certain components as meeting ISO/TS16949 requirements, mainly for automotive use. In any case of use of non-designated products, TI will not be responsible for any failure to meet ISO/TS16949. Products Applications Audio www.ti.com/audio Automotive and Transportation www.ti.com/automotive Amplifiers amplifier.ti.com Communications and Telecom www.ti.com/communications Data Converters dataconverter.ti.com Computers and Peripherals www.ti.com/computers DLP® Products www.dlp.com Consumer Electronics www.ti.com/consumer-apps DSP dsp.ti.com Energy and Lighting www.ti.com/energy Clocks and Timers www.ti.com/clocks Industrial www.ti.com/industrial Interface interface.ti.com Medical www.ti.com/medical Logic logic.ti.com Security www.ti.com/security Power Mgmt power.ti.com Space, Avionics and Defense www.ti.com/space-avionics-defense Microcontrollers microcontroller.ti.com Video and Imaging www.ti.com/video RFID www.ti-rfid.com OMAP Applications Processors www.ti.com/omap TI E2E Community e2e.ti.com Wireless Connectivity www.ti.com/wirelessconnectivity Mailing Address: Texas Instruments, Post Office Box 655303, Dallas, Texas 75265 Copyright © 2015, Texas Instruments Incorporated