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MCP47A1 Datasheet

Download or read online Microchip Technology MCP47A1 6-Bit Volatile DAC With Command Code pdf datasheet.



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6-Bit Volatile DAC with Command Code
Features:
• 6-Bit DAC
- 65 Taps: 64 Resistors with Taps to Full-Scale
and Zero-Scale (Wiper Code 00h to 40h)
• V
Pull-down Resistance: 20 k (typical)
REF
• V
Voltage Range
OUT
- V
to V
SS
REF
2
• I
C
Protocol
- Supports SMBus 2.0 Write Byte/Word
Protocol Formats
- Supports SMBus 2.0 Read Byte/Word
Protocol Formats
- Slave Addresses: 5Ch and 7Ch
• Brown-out Reset Protection (1.5V typical)
• Power-on Default Wiper Setting (Mid-scale)
• Low-Power Operation: 90 µA Static Current (typical)
• Wide Operating Voltage Range:
- 1.8V to 5.5V
• Low Tempco: 15 ppm (typical)
• 100 kHz (typical) Bandwidth (-3 dB) Operation
• Extended Temperature Range (-40° C to +125° C)
• Small Packages, SC70-6
• Lead Free (Pb-free) Package
Applications
• Set point or offset trimming
• Cost-sensitive mechanical trim pot replacement
 2012 Microchip Technology Inc.
MCP47A1
Package Types
MCP47A1
V
A
6 V
1
DD
REF
W
B
V
5 V
2
SS
OUT
SCL
SDA
3
4
SC70-6
Device Block Diagram
V
A
DD
Power-up
and
Brown-out
V
Control
SS
2-Wire
SDA
Interface
SCL
and
Control
Logic
B
Description
The MCP47A1 devices are volatile, 6-Bit digital
potentiometers with a buffered output. The wiper
2
setting is controlled through an I
C serial interface. The
2
I
C slave addresses of “010 1110” and “011 1110”
are supported.
V
REF
V
OUT
DS25154A-page 1

Summary of Contents

Page 1

... SS 2-Wire SDA Interface SCL and Control Logic B Description The MCP47A1 devices are volatile, 6-Bit digital potentiometers with a buffered output. The wiper 2 setting is controlled through serial interface. The slave addresses of 010 1110 and 011 1110 are supported. V REF ...

Page 2

... MCP47A1 Device Features Device 2 MCP47A1 (2) 2 MCP47DA1 MCP4706 I C 256 256 210 2 MCP4716 I C 1024 1024 210 2 MCP4726 I C 4096 4096 210 2 MCP4725 I C 4096 4096 N.A. Note 1: Analog characteristics only tested from 2.7V to 5.5V. 2: Refer to MCP47DA1 Data Sheet (DS25118). ...

Page 3

... Exposure to maximum rating conditions for extended periods may affect device reliability. 2012 Microchip Technology Inc. SS ... ) with respect ... ) ... ±20 mA > V )... ± 150° MCP47A1 -0. 0.3V DD -0. 0.3V DD DS25154A-page 3 ...

Page 4

... MCP47A1 AC/DC CHARACTERISTICS Standard Operating Conditions (unless otherwise specified) Operating Temperature DC Characteristics All parameters apply across the specified operating ranges unless noted Typical specifications represent values for V Parameters Sym Min Supply Voltage V 2.7 DD 1.8 V Start Voltage V DD BOR to ensure Wiper to default reset state ...

Page 5

... V REF from Code 00h (Zero-Scale) through Code 3Fh (Full-Scale - 1). OUT ), which changes significantly over voltage and W current. REF MCP47A1 125° C (extended) 5.5V 25° Conditions Device Output minimum drive Device Output maximum drive 400 pF, R ...

Page 6

... MCP47A1 AC/DC CHARACTERISTICS (CONTINUED) Standard Operating Conditions (unless otherwise specified) Operating Temperature DC Characteristics All parameters apply across the specified operating ranges unless noted Typical specifications represent values for V Parameters Sym Min Resistance R 16.0 VREF (± 20%) Resolution N Step Resistance R S R Nominal /T — ...

Page 7

... V REF from Code 00h (Zero-Scale) through Code 3Fh (Full-Scale - 1). OUT ), which changes significantly over voltage and W current. REF MCP47A1 125° C (extended) 5.5V 25° Conditions 1.8V V 5.5V DD 1.8V V 5. < 2.0V ...

Page 8

... MCP47A1 2 1 Mode Timing Waveforms and Requirements SCL 91 90 SDA START Condition 2 FIGURE 1- Bus Start/Stop Bits Timing Waveforms. 103 SCL 90 91 SDA In 109 SDA Out Refer to specification D102 (Cb) for load conditions. Note: 2 FIGURE 1- Bus Data Timing. 2 TABLE 1- BUS START/STOP BITS REQUIREMENTS ...

Page 9

... I R the SCL line is released. The MCP47A1 device must provide a data hold time to bridge the undefined part between V 3: the falling edge of the SCL signal. This specification is not a part of the I tested in order to guarantee that the output data will meet the setup and hold specifications for the receiving device ...

Page 10

... MCP47A1 TEMPERATURE CHARACTERISTICS Electrical Specifications: Unless otherwise indicated, V Parameters Temperature Ranges Specified Temperature Range Operating Temperature Range Storage Temperature Range Thermal Package Resistances Thermal Resistance, 6L-SC70 Note 1: Package Power Dissipation (  DIS where Junction Temperature DS25154A-page 10 2.7V to 5.5V ...

Page 11

... V DD 1.00 0.75 0.50 0.25 0.00 0.25 0.50 125C 2.7V 0.75 125C 1.8V 125C 1.0V 1. Analog Performance Specified for VDD 2.7V. FIGURE 2-4: and Temperature 1.8V MCP47A1 5 k nF. L Typical Device 40C 2.0V 25C 2.0V 85C 2.0V 125C 2.0V 40C 1.8V 25C 1.8V 85C 1.8V 125C 1.8V 40C 1.0V 25C 1.0V 85C 1.0V 125C 1. DAC Wiper Code INL vs ...

Page 12

... MCP47A1 Note: Unless otherwise indicated 25° Typical Device 0.50 40C 5.5V 25C 5.5V 85C 5.5V 40C 2.7V 25C 2.7V 85C 2.7V 40C 1.8V 25C 1.8V 85C 1.8V 40C 1.0V 25C 1.0V 85C 1.0V 0.25 0.00 0.25 0. DAC Wiper Code FIGURE 2-5: DNL vs. Code (00h to 3Fh) and Temperature 5.5V 5.5V, 2.7V, 1.8V, and 1.0V. DD REF Typical Device 0.50 40C 2.7V 25C 2 ...

Page 13

... FIGURE 2-11: Temperature 2.0V 0.00 1.00 2.00 3.00 4.00 FSE 1.6V FSE 1.0V 5.00 80 100 120 40 20 Analog Performance Specified for VDD 2.7V. FIGURE 2-12: Temperature 1.8V MCP47A1 5 k nF Typical Device 100 120 Temperature (°C) Full Scale Error (FSE) vs. 2.0V, 1.8V, and 1.0V. REF Typical Device 100 120 Temperature (° ...

Page 14

... MCP47A1 Note: Unless otherwise indicated 25° Typical Device 1.00 0.80 0.60 0.40 0.20 0. Temperature (°C) FIGURE 2-13: Zero Scale Error (ZSE) vs. Temperature 5.5V 5.5V, 2.7V, 1.8V, and 1.0V. DD REF Typical Device 1.00 0.80 0.60 0.40 0.20 0. Temperature (°C) FIGURE 2-14: Zero Scale Error (ZSE) vs. Temperature 2.7V 2.7V, 1.8V, and 1.0V. DD REF DS25154A-page 14 ...

Page 15

... When REF DD (code 64) 5. Analog Performance Specified for VDD 2.7V. FIGURE 2-20: Code and Temperature 1.8V MCP47A1 5 k nF. L Typical Device 40C 2.0V 25C 2.0V 85C 2.0V 125C 2.0V 40C 1.8V 25C 1.8V 85C 1.8V 125C 1.8V 40C 1.0V 25C 1.0V 85C 1.0V 125C 1. ...

Page 16

... MCP47A1 Note: Unless otherwise indicated 25° Typical Device 10.00 8.00 6.00 4.00 2. 0.00 2.00 4.00 6.00 8.00 10. DAC Wiper Code FIGURE 2-21: V Tempco vs. Code ( OUT ( OUT(125C) OUT(-40C) OUT(25C,CodeFS) / 165 ) 1,000,000 ), V 5.5V 5.5V, 2.7V, 1.8V, and 1.0V. DD REF Typical Device 14.00 12.00 10.00 8.00 6.00 4.00 2.00 0.00 2.00 4.00 6.00 8.00 10. DAC Wiper Code ...

Page 17

... DD FIGURE 2-28: (STATIC) vs. Temperature and 1.8V, 2.7V and 5.5V (no load MCP47A1 5 k nF Typical Device 400kHz 3.3V 400kHz 2.7V 400kHz 1.8V 100kHz 3.3V 100kHz 2.7V 100kHz 1. 100 120 Temperature (C) Interface Active Current ) and Temperature SCL ...

Page 18

... MCP47A1 Note: Unless otherwise indicated 25° Typical Device 1000 2000 3000 I (mA) SOURCE/SINK FIGURE 2-29: V vs. Resistive Load. OUT V 5.0V. DD Typical Device 2.7 1.8 0.9 0.0 0 1000 2000 3000 I (mA) SOURCE/SINK FIGURE 2-30: V vs. Resistive Load. OUT V 2.7V. DD DS25154A-page 5V 0V ...

Page 19

... Mid Scale VREF 5.5V Quarter Scale VREF 2.7V Quarter Scale VREF 5.5V 27.00 30. 100 Frequency (kHz) FIGURE 2-35: -3dB Bandwidth vs Frequency 5.5V. DD 2012 Microchip Technology Inc 5V 0V REF SS 80 100 120 and DD RVREF 1.8V 80 100 120 DD 1000 MCP47A1 5 k nF DS25154A-page 19 ...

Page 20

... MCP47A1 Note: Unless otherwise indicated 25° FIGURE 2-36: Zero-Scale to Full-Scale Settling Time (00h to 40h),  5.0V 5.0V REF L (Time scale 2 µs / div). FIGURE 2-37: Full-Scale to Zero-Scale Settling Time (40h to 00h),  5.0V 5.0V REF L (Time scale 2 µs / div). DS25154A-page 5V 0V, R ...

Page 21

... SCL V 20h (V Voltage Scale 20 mV/div, OUT OUT Time scale 2 µs / div). 2012 Microchip Technology Inc 5V 0V k REF SS L 2.1 Test Circuit V IN 4.0V (peak to peak) 1.0V DC FIGURE 2-41 Gain vs. Frequency Test. MCP47A1 1 nF REF W V OUT - DS25154A-page 21 ...

Page 22

... MCP47A1 NOTES: DS25154A-page 22 2012 Microchip Technology Inc. ...

Page 23

... Serial Clock (SCL) The SCL pin is the serial clock pin of the I The MCP47A1 acts only as a slave and the SCL pin accepts only external serial clocks. The SCL pin is an open-drain output. Refer to Section 5.0 Serial 2 for more details of I Interface - I C Module” ...

Page 24

... MCP47A1 NOTES: DS25154A-page 24 2012 Microchip Technology Inc. ...

Page 25

... GENERAL OVERVIEW The MCP47A1 device is a general purpose DAC intended to be used in applications where a program- mable voltage output with moderate bandwidth is desired. Applications generally suited for the MCP47A1 devices include: Set point or offset trimming Sensor calibration Cost-sensitive mechanical trim pot replacement The MCP47A1 has four main functional blocks ...

Page 26

... MCP47A1 4.1 POR/BOR Operation The Power-on Reset is the case where the device has power applied to it from V . The Brown-out Reset SS occurs when a device had power applied to it, and that power (voltage) drops below the specified range. The devices RAM retention voltage (V ...

Page 27

... Normal Operation Range V DD 1.8V V POR/BOR V RAM V SS FIGURE 4-2: Power-up and Brown-out. 2012 Microchip Technology Inc. Outside Specified Normal Operation Range AC/DC Range Below Minimum Operating Voltage Devices Serial V BOR Interface is Not Operational Wiper forced to default POR/BOR setting MCP47A1 delay DS25154A-page 27 ...

Page 28

... MCP47A1 NOTES: DS25154A-page 28 2012 Microchip Technology Inc. ...

Page 29

... C Module is compatible with the NXP I specification (# UM10204). Only the field types, field lengths, timings, etc frame are defined. The frame content defines the behavior of the device. The frame content for the MCP47A1 device is defined in this sec- tion of the data sheet. 2 Figure 5-1 shows a typical I C bus configuration ...

Page 30

... SCL goes low before SDA is asserted low. This may indicate that another master is attempting to transmit a data "1". A SDA 9 SCL FIGURE 5-5: Waveform. MCP47A1 RESPONSES Acknowledge Comment Bit Response N. Module Resets Dont Care if ...

Page 31

... CLOCK STRETCHING Clock Stretching is something that the secondary device can do, to allow additional time to respond to the data that has been received. The MCP47A1 will not stretch the clock signal (SCL) since memory read accesses occur fast enough. SDA SCL ...

Page 32

... The MCP47A1 does not support hardware address bits. 5.2.10 GENERAL CALL The General Call is a method that the Master device can communicate with all other Slave devices. The MCP47A1 devices do not respond to General Call address and communications are Not Acknowledged. Second Byte ...

Page 33

... Command Code, while the second Control Byte requires the R/W bit equal to a logic one (R/W 1) to generate a read sequence. The MCP47A1 will A the Slave Address Byte and A all the 2 Data Bytes. The I C Master will A the Slave Address Byte and the last Data Byte ...

Page 34

... MCP47A1 Fixed Address (1) Slave Address Byte Legend S Start Condition P Stop Condition A Acknowledge X Dont Care R/W Read/Write bit D6:D0 Data bits Note 1: Example using Slave Address Option A0 (5Ch). 2 FIGURE 5-11 Single Byte Write Command Format. Fixed Address ...

Page 35

... Microchip Technology Inc Command Code K Data Byte Command Code K Data Byte 0 0 Data Byte MCP47A1 DS25154A-page 35 ...

Page 36

... Note 1: Master Device is responsible for ACK / NACK signal NACK signal occurs, the MCP47A1 will abort this transfer and release the bus. 2: The Master Device will Not ACK, and the MCP47A1 will release the bus so the Master Device can generate a Stop or Repeated Start condition. ...

Page 37

... ZS I VREF VREF Where the V FS OUT full-scale the V ZS OUT zero-scale. MCP47A1 resistor ladder AB Figure 6-1). resistors in the R ladder equals OUT resistance also includes the R and FS Section 6.2.2). The R (and resistance is 10k 6.3). AND R RESISTORS ...

Page 38

... MCP47A1 Resistor Network (Section 6.0) Note 1: The wiper resistance is tap dependent. That is, each tap selection resistance has a small variation. FIGURE 6-1: Resistor Network and Output Buffer Block Diagram. DS25154A-page 38 (40h) ( ...

Page 39

... Sales Office for additional information. Custom options have NRE and minimum volume requirements. (1/ REF V REF 2 C Read com- MCP47A1 REF ) of the device has minimal variation VREF pins voltage is ratiometric, and the pins voltage. OUT shows the default values offered. POR/BOR SETTINGS ...

Page 40

... MCP47A1 NOTES: DS25154A-page 40 2012 Microchip Technology Inc. ...

Page 41

... EQUATION 7- the V FS OUT full-scale the V ZS zero-scale. Table 7-1 shows the calculated V given volatile Wiper Register value. These calculations are based on different V and 5.0V) with an assumption that R MCP47A1 7-1. CALCULATING OUTPUT VOLTAGE (V ) OUT ( 0 ...

Page 42

... MCP47A1 TABLE 7-1: THEORETICAL DAC OUTPUT VALUES ( V OUT Wiper Value V Ratio Hex Dec 1.5 00h 0 0.0000 0.0000 0.0000 01h 1 0.0156 0.0234 0.0516 02h 2 0.0313 0.0469 0.1031 03h 3 0.0469 0.0703 0.1547 04h 4 0.0625 0.0938 0.2063 05h 5 0.0781 0.1172 0.2578 06h 6 0.0938 0.1406 0.3094 07h 7 0 ...

Page 43

... DAC Code. The DAC Register Figure 2- code the full-scale code. 1.6V. Higher V OUT V REF W DAC Code FIGURE 7-3: DAC Register Code REF ) to W MCP47A1 OUT voltage, or the maximum DAC REF voltages below the DD OUT voltage. REF voltage as the V voltage NL OUT REF DAC Code V REF ...

Page 44

... MCP47A1 7.2 Output Slew Rate Figure 7-4 shows an example of the slew rate of the V pin. The slew rate can be affected by the OUT characteristics of the circuit connected to the V V OUT(B) V OUT(A) Wiper A Wiper B Time OUT(B) OUT(A) Slew Rate T FIGURE 7-4: V Pin Slew Rate. OUT 7 ...

Page 45

... Step Voltage (V V OUT(ZS) When 5.0V V 78.125mV 42.19mV S when Error. OUT MCP47A1 CALCULATION COMPARISON Example Theoretical Delta 20,180 100 0 100 80 0 80 30,000 30,180 - 180 10,000 10,060 - 60 5.00 V — ...

Page 46

... MCP47A1 NOTES: DS25154A-page 46 2012 Microchip Technology Inc. ...

Page 47

... Output Building Programmable Current Source Serial Interface Communication Times Software I2C Interface Reset Sequence In the design of a system with the MCP47A1 devices, the following considerations should be taken into account: Power Supply Considerations (Noise) PCB Area Requirements • ...

Page 48

... MCP47A1 8.1.1 DECREASING OUTPUT STEP SIZE Due to the step voltage and output range of the MCP47A1, it may be desirable to reduce the step voltage while also modifying the range of the output. A common method to achieve this smaller step size is a voltage divider on the DACs output. ...

Page 49

... R 2 EQUATION 8- OA OUT Note CC account R resistor ladder (see R information). 2 MCP47A1 GAIN CALCULATION selected as 20 k 1 BIPOLAR WINDOW DAC CALCULATIONS • • Gain Adjust • R ...

Page 50

... The current sensor resistor is used to convert the DAC voltage output into a digitally-selectable current source. The smaller R is, the less power is dissipated SENSE across it. However, this also reduces the resolution that the current can be controlled REF OUT MCP47A1 2 V I C CC 2-wire ---- b  ...

Page 51

... Microchip Technology Inc. The nine bits of 1 are used to force a Reset of those devices that could not be reset by the previous Start bit. This occurs only if the MCP47A1 is driving an A bit on 2 the I C bus output mode (from a Read command) and is driving a data bit of ‘ ...

Page 52

... CONSIDERATIONS (NOISE) Inductively-coupled AC transients and digital switching noise can degrade the input and output signal integrity, potentially masking the MCP47A1s performance. Careful board layout minimizes these effects and increases the Signal-to-Noise Ratio (SNR). Multi-layer boards utilizing a low-inductance ground plane, isolated inputs, isolated outputs and proper decoupling are suggested ...

Page 53

... C command protocol structure. 2012 Microchip Technology Inc. 8.6.4 CONNECTING TO I PULL-UP RESISTORS The SCL and SDA pins of the MCP47A1 devices are open-drain configurations. These pins require a pull-up resistor as shown in (1) The pull-up resistor values (R1 and R2) for SCL and SDA pins depend on the operating speed (standard, ...

Page 54

... MCP47A1 NOTES: DS25154A-page 54 2012 Microchip Technology Inc. ...

Page 55

... DEVELOPMENT SUPPORT 9.1 Evaluation/Demonstration Boards The MCP47A1 devices do not have a dedicated evaluation or demonstration board. Figure 9-1 the component connections to make an evaluation board using the SC70EV Bond Out PCB (order # SC70EV). This will allow the MCP47A1s capabilities to be evaluated with the PICkit Serial Analyzer (order # DV164122). 0  ...

Page 56

... MCP47A1 9.2 Technical Documentation Several additional technical documents are available to assist you in your design and development. These technical documents include Application Technical Briefs, and Design Guides. Table 9-1 some of these documents. TABLE 9-1: TECHNICAL DOCUMENTATION Application Title Note Number AN1326 Using DAC for LDMOS Amplifier Bias Control Applications — ...

Page 57

... In the event the full Microchip part number cannot be marked on one line, it will Note: be carried over to the next line, thus limiting the number of available characters for customer-specific information. 2012 Microchip Technology Inc. Example BANN Code Part Number Code BANN MCP47A1T-A1E/LT BCNN MCP47A1 ) e 3 DS25154A-page 57 ...

Page 58

... MCP47A1 Note: For the most current package drawings, please see the Microchip Packaging Specification located at http://www.microchip.com/packaging DS25154A-page 58 2012 Microchip Technology Inc. ...

Page 59

... Note: For the most current package drawings, please see the Microchip Packaging Specification located at http://www.microchip.com/packaging 2012 Microchip Technology Inc. MCP47A1 DS25154A-page 59 ...

Page 60

... MCP47A1 Note: For the most current package drawings, please see the Microchip Packaging Specification located at http://www.microchip.com/packaging DS25154A-page 60 2012 Microchip Technology Inc. ...

Page 61

... APPENDIX A: REVISION HISTORY Revision A (August 2012) Original Release of this Document. 2012 Microchip Technology Inc. MCP47A1 DS25154A-page 61 ...

Page 62

... OUT(FS) OUT(ZS LSb (MCP47A1) B.3 Monotonic Operation Monotonic operation means that the devices output voltage (V ) increases with every one code step OUT (LSb) change (from terminal B to terminal A). The V voltage (V voltage) is the sum of all the Step voltages W plus the voltage at Zero-Scale (V ) ...

Page 63

... FIGURE B-3: SCALE ERROR EXAMPLE. B.10 Gain Error Drift The Gain error drift is the variation in gain error due to a change in ambient temperature. The gain error drift is typically expressed in ppm/ MCP47A1 Figure B-3) is the difference Actual Transfer Function Full-Scale Error Gain Error Actual Transfer Function ...

Page 64

... INL error for these devices is the maximum deviation between an actual code transition point and its corresponding ideal transition point after offset and gain errors have been removed. These endpoints are from 0x00 to 0x40 for the MCP47A1. Refer to 4. Positive INL means higher V voltage than ideal. ...

Page 65

... This time is measured from the start of code transition, to when the V voltage is within the specified accuracy. OUT In the MCP47A1, the settling time is a measure of the time delay until the V voltage reaches within 0.5 OUT LSb of its final value, when the volatile DAC Register changes from 40h to 50h ...

Page 66

... MCP47A1 NOTES: DS25154A-page 66 2012 Microchip Technology Inc. ...

Page 67

... C to 125° C Range: Package Plastic Small Outline Transistor (SC70), 6-lead 2012 Microchip Technology Inc. Examples: /XX a) Package interface MCP47A1 . MCP47A1T-A0E/LT: 6-bit DAC, SC70-6, Address 5Ch, Tape and Reel MCP47A1T-A1E/LT: 6-bit DAC, SC70-6, Address 7Ch, Tape and Reel DS25154A-page 67 ...

Page 68

... MCP47A1 NOTES: DS25154A-page 68 2012 Microchip Technology Inc. ...

Page 69

... PICtail, REAL ICE, rfLAB, Select Mode, Total Endurance, TSHARC, UniWinDriver, WiperLock and ZENA are trademarks of Microchip Technology Incorporated in the U.S.A. and other countries. SQTP is a service mark of Microchip Technology Incorporated in the U.S.A. All other trademarks mentioned herein are property of their respective companies. © 2012, Microchip Technology Incorporated, Printed in the U ...

Page 70

... Singapore Tel: 65-6334-8870 Fax: 65-6334-8850 Taiwan - Hsin Chu Tel: 886-3-5778-366 Fax: 886-3-5770-955 Taiwan - Kaohsiung Tel: 886-7-536-4818 Fax: 886-7-330-9305 Taiwan - Taipei Tel: 886-2-2500-6610 Fax: 886-2-2508-0102 Thailand - Bangkok Tel: 66-2-694-1351 Fax: 66-2-694-1350 2012 Microchip Technology Inc. 11/29/11 ...

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