ADN2850 Analog Devices, Inc., ADN2850 Datasheet
ADN2850
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ADN2850 Summary of contents
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... EEMEM . Another key feature of the ADN2850 is that the actual tolerance is stored in the EEMEM. The actual full-scale resistance can therefore be known, which is valuable for tolerance matching and calibration. In the scratch pad programming mode, a specific setting can be ...
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... ADN2850–SPECIFICATIONS ELECTRICAL CHARACTERISTICS 250 k VERSIONS Parameter DC CHARACTERISTICS RHEOSTAT MODE (Specifications apply to all RDACs) 3 Resistor Differential Nonlinearity 3 Resistor Integral Nonlinearity Resistance Temperature Coefficient Wiper Resistance Channel Resistance Matching Nominal Resistor Tolerance RESISTOR TERMINALS 4 Terminal Voltage Range 5 Capacitance Bx 5 Capacitance Wx 6 Common-Mode Leakage Current ...
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... Endurance is qualified to 100,000 cycles as per JEDEC Std. 22 method A117 and measured at –40 °C, +25°C, and +85°C; typical endurance at +25°C is 700,000 cycles Retention lifetime equivalent at junction temperature (T derate with junction temperature. Specifications subject to change without notice. The ADN2850 contains 16,000 transistors. Die size: 93 mil REV. B Symbol Conditions ...
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... ADN2850 TIMING DIAGRAMS CLK CPOL = SDO * SDI t 14 RDY *NOT DEFINED, BUT NORMALLY LSB OF CHARACTER PREVIOUSLY TRANSMITTED. THE CPOL = 1 MICROCONTROLLER COMMAND ALIGNS THE INCOMING DATA TO THE POSITIVE EDGE OF THE CLOCK CLK CPOL = SDO MSB OUT SDI MSB IN ...
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... ADN2850BRU25 25 ADN2850BRU25-RL7 25 *Line 1 contains product number, ADN2850, line 2 Top Mark branding contains differentiating detail by part type, line 3 contains lot number, line 4 contains product date code YYWW. CAUTION ESD (electrostatic discharge) sensitive device. Electrostatic charges as high as 4000 V readily accumulate on the human body and test equipment and can discharge without detection. Although the ADN2850 features proprietary ESD protection circuitry, permanent damage may occur on devices subjected to high energy electrostatic discharges ...
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... SDI Serial Data Input Pin. Shifts in one bit at a time on positive clock CLK edges. MSB loaded first. PIN CONFIGURATIONS ADN2850BRU PIN FUNCTION DESCRIPTIONS Pin No. Mnemonic Description 1 CLK 2 SDI 3 SDO 4 GND ...
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... X • • • • • • X Increment contents of RDAC(A0) by “One,” stops X • • • • • • • • • • X Increment contents of all RDAC Registers by “One,” –7– ADN2850 Data Byte example ...
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... ADN2850 OPERATIONAL OVERVIEW The ADN2850 programmable resistor is designed to operate as a true variable resistor. The resistor wiper position is determined by the RDAC register contents. The RDAC register acts as a scratch pad register which allows unlimited changes of resistance settings. The scratch pad register can be programmed with any position setting using the standard SPI serial interface by loading the 24-bit data-word ...
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... Numbers of Bits Only (Even Numbers of Bits Are Ideal) REV. B Using Additional Internal Nonvolatile EEMEM The ADN2850 contains additional internal user storage registers (EEMEM) for saving constants and other 16-bit data. Table V provides an address map of the internal storage registers shown in the functional block diagram as EEMEM1, EEMEM2, and ...
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... SDO-SDI interface may induce time delay to the subsequent devices (see Figure 4). If two ADN2850s are daisy-chained, a total 48 bits of data is required. The first 24 bits (formatted 4-bit instruction, 4-bit address, and 16-bit data and the second 24 bits with the same format ...
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... SS forward biased diodes (see Figure 7). Figure 7. Maximum Terminal Voltages Set by V The ground pin of the ADN2850 device is primarily used as a digital ground reference that needs to be tied to the PCB’s common ground. The digital input control signals to the ADN2850 must be referenced to the device ground pin (GND), and satisfy the logic level defined in the Specifications table of this data sheet ...
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... ADN2850 for data 001 . The third connection is the next tap point represent- H ( 98.8 Ω for data 002 ing R WB LSB data value increase moves the wiper up the resistor ladder until the last tap point is reached Figure 9 for a simplified diagram of the equivalent RDAC circuit. ...
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... VERSION –40 250k VERSION –60 –80 0 128 256 384 512 CODE – Decimal TPC 3. ∆ ∆ T Rheostat Mode Tempco WB REV. B Typical Performance Characteristics–ADN2850 +25 C –40 C +85 C 800 1000 800 1000 = 0. 5.0V/ ...
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... ADN2850 0.5V/DIV MIDSCALE TPC 7. Memory Restore During Power-On Reset 4ms/DIV TPC 8. I vs. Time (Save) Program Mode DD 4ms/DIV SUPPLY CURRENT RETURNS TO MINIMUM POWER CONSUMPTION IF INSTRUCTION 0 (NOP) IS EXECUTED IMMEDIATELY AFTER INSTRUCTION 1 (READ EEMEM) TPC 9. I vs. Time (Read) Program Mode ...
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... PROGRAMMING EXAMPLES The following programming examples illustrate the typical sequence of events for various features of the ADN2850. Users should refer to Table II for the instructions and data-word format. The instruc- tion numbers, addresses, and data appearing at SDI and SDO pins are displayed in hexadecimal format in the following examples. ...
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... ADN2850 forms an optical supervisory system where the dual programmable resistors are used to set the laser average optical power and extinction ratio (see Figure 11). The ADN2850 is particularly ideal for the optical parameter settings because of its high resolution, compact footprint, and superior temperature coefficient characteristics ...
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... C and T A Resistance Scaling The ADN2850 offers either 25 kΩ or 250 kΩ full-scale resistance. Users who need lower resistance and still maintain the numbers of step adjustment can parallel two or more devices. Figure 14 shows a simple scheme of paralleling both channels of the pro- grammable resistors ...
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... ADN2850 PIN 1 INDICATOR 0.90 MAX 0.85 NOM 16-Lead Thin Shrink Small Outline Package [TSSOP] 0.15 0.05 OUTLINE DIMENSIONS 16-Lead Frame Chip Scale Package [LFCSP Body (CP-16 5x5) Dimensions shown in millimeters 5.0 BSC SQ 0.60 MAX 0.80 BSC TOP 4.75 VIEW BSC SQ 0.75 0.60 0.50 0.70 MAX 12 MAX 0.65 NOM 0.05 MAX 0.01 NOM 0.40 0.20 REF 0.33 COPLANARITY SEATING ...
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... Revision History Location 9/02—Data sheet changed from REV REV. B. Changes to GENERAL DESCRIPTION . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1 Changes to ELECTRICAL CHARACTERISTICS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2 Changes to Calculating Actual Full-Scale Resistance section . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9 Changes to Table Updated OUTLINE DIMENSIONS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 18 REV. B –19– ADN2850 Page ...
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