MCP3421 Microchip Technology, MCP3421 Datasheet
MCP3421
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MCP3421 Summary of contents
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... This reduces current consumption greatly during idle periods. The MCP3421 device can be used for various high accuracy analog-to-digital data conversion applications where design simplicity, low power, and small footprint are major considerations. ...
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... MCP3421 1.0 ELECTRICAL CHARACTERISTICS Absolute Maximum Ratings† V ...................................................................................7.0V DD All inputs and outputs w.r.t V ............... –0. Differential Input Voltage ...................................... |V Output Short Circuit Current .................................Continuous Current at Input Pins ....................................................±2 mA Current at Output and Supply Pins ............................±10 mA Storage Temperature.....................................-65°C to +150°C Ambient Temp. with power applied ...............-55°C to +125°C ESD protection on all pins ................ ≥ ...
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... REF MCP3421 = +5.0V 0V Units Conditions ppm 3.75 SPS (Note 6) FSR V % PGA = 3.75 SPS % Between any 2 PGA gains ppm/°C PGA=1, DR=3.75 SPS µV Tested at PGA = 5.0V and DR = 3.75 SPS DD nV/° ...
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... MCP3421 2.0 TYPICAL PERFORMANCE CURVES Note: The graphs and tables provided following this note are a statistical summary based on a limited number of samples and are provided for informational purposes only. The performance characteristics listed herein are not tested or guaranteed. In some graphs or tables, the data presented may be outside the specified operating range (e ...
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... -60 -40 -20 FIGURE 2-10: 0 -10 -20 -30 -40 -50 -60 -70 -80 - 2.7V -100 DD -110 -120 0.1 0.1 FIGURE 2-11: MCP3421 + = / REF = 2. 100 120 140 Temperature (°C) OSC Drift vs. Temperature. Data Rate = 3.75 SPS 100 100 1k 1000 10k 10000 Input Signal Frequency (Hz) Frequency Response ...
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... The input data from the Master device is shifted into the SDA pin on the rising edges of the SCL clock and output from the MCP3421 occurs at the falling edges of the SCL clock. The SCL pin is an open-drain N-channel driver. Therefore, it needs a pull-up resistor from the V to the SCL pin. Refer to Section 5.3 “ ...
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... Section 1.0 “Electrical Characteristics”. 4.5 Digital Output Code The digital output code produced by the MCP3421 is a function of PGA gain, input signal, and internal reference voltage fixed setting, the digital output code is proportional to the voltage difference between the two analog inputs ...
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... Input Impedance The MCP3421 uses a switched-capacitor input stage using a 3.2 pF sampling capacitor. This capacitor is switched (charged and discharged rate of the sampling frequency that is generated by the on-board clock. The differential mode impedance varies with the PGA settings ...
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... Although the MCP3421 device has an internal first order sinc filter, its’ filter response may not give enough attenuation to all aliasing signal components. To avoid ...
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... The user operates the device by setting up the device configuration register and reads the conversion data 2 using serial I C interface commands. The MCP3421 operates in two modes: (a) Continuous Conversion Mode or (b) One-Shot Conversion Mode (single conversion). The selection is made by setting the O/C bit in the Configuration Register. Refer to Section 5.2 “ ...
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... One-Shot Conversion mode Initiate a new conversion effect. bit 6-5 C1-C0: Channel Selection Bits These are the Channel Selection bits, but not used in the MCP3421 device. bit 4 O/C: Conversion Mode Bit 1 = Continuous Conversion Mode. Once this bit is selected, the device performs data conversions continuously. ...
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... bidirectional 2-wire data bus communication protocol using open- drain SCL and SDA lines. The MCP3421 can only be addressed as a slave. Once addressed, it can receive configuration bits or transmit the latest conversion results. The serial clock pin (SCL input only and the serial data pin (SDA) is bidirectional ...
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... MCP3421 outputs the conversion data bytes and configuration byte. Each byte consists of 8 bits with one acknowledge (ACK) bit. The ACK bit after the address byte is issued by the MCP3421 and the ACK bits after each conversion data bytes are issued by the Master. ...
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... MCP3421 FIGURE 5-2: Timing Diagram For Reading From The MCP3421 With 18-Bit Mode. DS22003B-page 14 © 2006 Microchip Technology Inc. ...
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... FIGURE 5-3: Timing Diagram For Reading From The MCP3421 With 12-Bit to 16-Bit Modes. © 2006 Microchip Technology Inc. MCP3421 DS22003B-page 15 ...
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... Stop bit can be issued any time during writing. – MCP3421 device code is 1101. – Address Bits A2 000 are programmed at factory unless customer requests different codes. FIGURE 5-4: Timing Diagram For Writing To The MCP3421. 5.4 General Call The MCP3421 acknowledges the general call address (0x00 in the first byte) ...
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... During reads, the Master (microcontroller) can terminate the current read operation by not providing an acknowledge bit on the last byte that has been clocked out from the MCP3421. In this case, the MCP3421 releases the SDA line to allow the master (microcontroller) to generate a STOP or repeated START condition ...
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... MCP3421 2 TABLE 5- SERIAL TIMING SPECIFICATIONS Electrical Specifications: Unless otherwise specified, all limits are specified for 0V / REF Parameters Sym Standard Mode Clock frequency f SCL Clock high time T HIGH Clock low time T LOW (Note 1) SDA and SCL rise time ...
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... C specification. This specification is equivalent to the Data Hold Time ( = HD:DAT can be affected. LOW . If this parameter is too long, the Data Input Setup (T SP MCP3421 = +2.7V, +3.3V or +5.0V, DD Units Conditions MHz C = 100 pF b MHz C = 400 100 400 pF ...
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... MCP3421 SCL SU:STA T LOW T SDA HD:STA FIGURE 5- Bus Timing Data. DS22003B-page 20 T HIGH T SU:DAT T HD:DAT SU:STO T BUF © 2006 Microchip Technology Inc. ...
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... CONNECTING BUS USING PULL-UP RESISTORS The SCL and SDA pins of the MCP3421 are open-drain configurations. These pins require a pull-up resistor as shown in Figure 6-1. The value of these pull-up resis- tors depends on the operating speed (standard, fast, and high speed) and loading capacitance of the I © ...
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... SDA Start Bit Address bits Device bits 2 FIGURE 6- Bus Connection Test. 6.3 Application Examples The MCP3421 device can be used in a broad range of sensor and data acquisition applications. shows an example of interfacing with a bridge sensor for pressure measurement. DS22003B-page NPP301 MCP3421 ...
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... Note: In the event the full Microchip part number cannot be marked on one line, it will be carried over to the next line, thus limiting the number of available characters for customer-specific information. © 2006 Microchip Technology Inc. MCP3421 Example CA25 ) e 3 ...
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... MCP3421 6-Lead Plastic Small Outline Transistor (OT) (SOT-23) Note: For the most current package drawings, please see the Microchip Packaging Specification located at http://www.microchip.com/packaging β Dimension Limits Number of Pins Pitch Outside lead pitch Overall Height Molded Package Thickness Standoff Overall Width ...
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... APPENDIX A: REVISION HISTORY Revision B (December 2006) • Changes to Electrical Characteristics tables • Added characterization data 2 • Changes Serial Timing Specification table • Change to Figure 5-7. Revision A (August 2006) • Original Release of this Document. © 2006 Microchip Technology Inc. MCP3421 DS22003B-page 27 ...
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... MCP3421 NOTES: DS22003B-page 28 © 2006 Microchip Technology Inc. ...
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... PRODUCT IDENTIFICATION SYSTEM To order or obtain information, e.g., on pricing or delivery, refer to the factory or the listed sales office PART NO Device Address Temperature Options Range MCP3421T: Single Channel ΔΣ A/D Converter Device: (Tape and Reel) Address Options ...
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... MCP3421 NOTES: DS22003B-page 30 © 2006 Microchip Technology Inc. ...
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... Select Mode, Smart Serial, SmartTel, Total Endurance, UNI/O, 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. © 2006, Microchip Technology Incorporated, Printed in the U ...
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... Taiwan - Kaohsiung Tel: 886-7-536-4818 Fax: 886-7-536-4803 Taiwan - Taipei Tel: 886-2-2500-6610 Fax: 886-2-2508-0102 Thailand - Bangkok Tel: 66-2-694-1351 Fax: 66-2-694-1350 © 2006 Microchip Technology Inc. EUROPE Austria - Wels Tel: 43-7242-2244-39 Fax: 43-7242-2244-393 Denmark - Copenhagen Tel: 45-4450-2828 Fax: 45-4485-2829 France - Paris ...