9-2229; Rev 0; 10/01 Low-Power, 16-Bit Multichannel DAS with Internal Reference,10-Bit DACs, and RTC The MAX1407/MAX1408/MAX1414 are available in space-saving 28-pin SSOP packages, while the MAX1409 is available in a 20-pin SSOP package. Applications Medical Instruments Industrial Control Systems Portable Equipment Data-Acquisition System Features ♦ +2.7V to +3.6V Supply Voltage Range in Standby, Idle, and Run Mode (Down to 1.8V in Sleep Mode) ♦ 1.15mA Run Mode Supply Current ♦ 2.
MAX1407/MAX1408/MAX1409/MAX1414 Low-Power, 16-Bit Multichannel DAS with Internal Reference,10-Bit DACs, and RTC ABSOLUTE MAXIMUM RATINGS AVDD to AGND .........................................................-0.3V to +6V AVDD to DVDD ...................................................... -0.3V to +0.3V Analog Inputs to AGND .........................-0.3V to +(AVDD + 0.3V) Digital Inputs to DGND.............................................-0.3V to +6V Maximum Current Input Into Any Pin ......................
Low-Power, 16-Bit Multichannel DAS with Internal Reference,10-Bit DACs, and RTC (DVDD = AVDD = +2.7V to 3.6V, 4.7µF at REF, internal VREF, 18nF between CPLL and AVDD, 32.768kHz crystal across CLKIN and CLKOUT, TA = TMIN to TMAX, unless otherwise noted. Typical values are at TA = +25°C.
MAX1407/MAX1408/MAX1409/MAX1414 Low-Power, 16-Bit Multichannel DAS with Internal Reference,10-Bit DACs, and RTC ELECTRICAL CHARACTERISTICS (continued) (DVDD = AVDD = +2.7V to 3.6V, 4.7µF at REF, internal VREF, 18nF between CPLL and AVDD, 32.768kHz crystal across CLKIN and CLKOUT, TA = TMIN to TMAX, unless otherwise noted. Typical values are at TA = +25°C.) PARAMETER SYMBOL CONDITIONS MIN TYP MAX UNITS Output Slew Rate 010hex to 3FFhex and 3FFhex to 010hex code swing, RL = 12kΩ, CL = 200pF 18.
Low-Power, 16-Bit Multichannel DAS with Internal Reference,10-Bit DACs, and RTC (DVDD = AVDD = +2.7V to 3.6V, 4.7µF at REF, internal VREF, 18nF between CPLL and AVDD, 32.768kHz crystal across CLKIN and CLKOUT, TA = TMIN to TMAX, unless otherwise noted. Typical values are at TA = +25°C.) PARAMETER SYMBOL RESET Output Leakage CONDITIONS MIN AVDD > VTH, RESET deasserted TYP MAX 0.002 0.1 Turn-On Time UNITS µA 2 ms 32.
MAX1407/MAX1408/MAX1409/MAX1414 Low-Power, 16-Bit Multichannel DAS with Internal Reference,10-Bit DACs, and RTC ELECTRICAL CHARACTERISTICS (continued) (DVDD = AVDD = +2.7V to 3.6V, 4.7µF at REF, internal VREF, 18nF between CPLL and AVDD, 32.768kHz crystal across CLKIN and CLKOUT, TA = TMIN to TMAX, unless otherwise noted. Typical values are at TA = +25°C.) PARAMETER SYMBOL CONDITIONS D0 Output Low Voltage (MAX1407/MAX1408/MAX1414 only) ISINK = 200µA, DVDD = +2.7V to +3.
Low-Power, 16-Bit Multichannel DAS with Internal Reference,10-Bit DACs, and RTC (MAX1407/MAX1408/MAX1409/MAX1414: AVDD = DVDD = 2.7V to 3.6V, TA = TMIN to TMAX, unless otherwise noted.) PARAMETER SYMBOL CONDITIONS MIN TYP MAX UNITS TYPICAL TIMING PARAMETERS OUT1/OUT2 Turn-Off Time Input impedance > 1MΩ (MAX1407/MAX1409/MAX1414 only) 100 µs Sleep Voltage Monitor Timeout Period The delay for the sleep voltage monitor output, RESET, to go high after AVDD rises above the reset threshold (+1.
Load Circuits DVDD DVDD 6kΩ 6kΩ DOUT DOUT DOUT DOUT CLOAD 50pF 6kΩ CLOAD 50pF a) VOH TO HIGH-Z CLOAD 50pF 6kΩ DGND DGND CLOAD 50pF DGND DGND a) HIGH-Z TO VOH AND VOL TO VOH b) VOL TO HIGH-Z LOAD CIRCUITS FOR DISABLE TIME b) HIGH-Z TO VOL AND VOH TO VOL LOAD CIRCUITS FOR ENABLE TIME Typical Operating Characteristics (AVDD = DVDD = 3V, MAX1407 used, TA = +25°C, unless otherwise noted.) SUPPLY CURRENT vs. SUPPLY VOLTAGE SUPPLY CURRENT vs.
Low-Power, 16-Bit Multichannel DAS with Internal Reference,10-Bit DACs, and RTC (AVDD = DVDD = 3V, MAX1407 used, TA = +25°C, unless otherwise noted.) MAXIMUM INL vs. VDD (UNIPOLAR MODE, T = +25°C, PSEUDO-DIFFERENTIAL INPUT) MAXIMUM INL vs. VDD (BIPOLAR MODE, T = +25°C, FULLY DIFFERENTIAL INPUT) 3 2 A 4.0 B 1 MAX1407 toc06 4.5 MAXIMUM INL (LSB) 4 MAXIMUM INL (LSB) 5.0 MAX1407 toc05 5 3.5 3.0 A 2.5 B 2.0 1.5 1.0 0.5 0 2.7 2.9 3.1 VDD (V) 3.3 0 3.5 2.
Typical Operating Characteristics (continued) (AVDD = DVDD = 3V, MAX1407 used, TA = +25°C, unless otherwise noted.) MAXIMUM INL vs. COMMON-MODE INPUT VOLTAGE (BIPOLAR MODE, BUFFERED MODE, VDD = 2.7V, 30sps, FULLY DIFFERENTIAL INPUT, T = +25°C) 2.0 MAX1407 toc10 2.5 1.5 B 1.0 2.0 INL (LSB) MAXIMUM INL (LSB) INL vs. FULLY DIFFERENTIAL INPUT VOLTAGE (BIPOLAR MODE, GAIN = 1, UNBUFFERED MODE, VCM = 0.625V, VDD = 3V, T = +25°C) MAX1407 toc09 3.0 1.5 A 0.5 0 -0.5 1.0 -1.0 0.5 -1.5 0 -2.0 0.3 0.
Low-Power, 16-Bit Multichannel DAS with Internal Reference,10-Bit DACs, and RTC REFERENCE VOLTAGE vs. TEMPERATURE 0 -0.02 0.10 % DEVIATION D 0.09 A 0.08 C -0.04 -0.06 -0.08 0.07 -0.12 20 0 40 60 -15 REFERENCE VOLTAGE vs. SUPPLY VOLTAGE 1.24406 1.24404 1.24402 1.24400 1.24398 35 60 85 2.85 3.00 3.15 3.30 SUPPLY VOLTAGE (V) 3.45 3.60 200 400 600 800 1000 DAC OFFSET ERROR vs. TEMPERATURE DAC OFFSET ERROR vs. SUPPLY VOLTAGE IDLE MODE -3.8 -4.400 1200 IDLE MODE -4.425 -4.
Typical Operating Characteristics (continued) (AVDD = DVDD = 3V, MAX1407 used, TA = +25°C, unless otherwise noted.) IDLE MODE 0.10 -0.15 0.15 MAX1407 toc20 0 MAX1407 toc19 0.15 DAC INTEGRAL NONLINEARITY vs. DIGITAL CODE (AVDD = 2.7V) DAC GAIN ERROR vs. SUPPLY VOLTAGE IDLE MODE 0.05 MAX1407 toc21 DAC GAIN ERROR vs. TEMPERATURE 0.10 -0.45 -0.60 -0.75 -0.90 0.05 0 INL (LSB) GAIN ERROR (LSB) GAIN ERROR (LSB) -0.30 -0.05 0 -0.10 -0.05 -0.15 -0.10 -1.05 -1.
Low-Power, 16-Bit Multichannel DAS with Internal Reference,10-Bit DACs, and RTC (AVDD = DVDD = 3V, MAX1407 used, TA = +25°C, unless otherwise noted.) 1.2435 DAC OUTPUT VOLTAGE (V) 1.2440 1.20 1.15 1.10 1.05 1.00 1.2430 3.0 3.3 0 3.6 1 2 3 4 5 1.70 1.65 1.60 1.55 1.50 1.45 1.40 1.35 1.30 1.25 1.20 0 6 5 10 25 30 35 40 VREF = 1.24406V IREF = 0 0.10 MAX1407 toc30 0.15 0.09 20 VOLTAGE MONITOR THRESHOLD vs. TEMPERATURE DAC OUTPUT VOLTAGE vs. TEMPERATURE 0.
MAX1407/MAX1408/MAX1409/MAX1414 Low-Power, 16-Bit Multichannel DAS with Internal Reference,10-Bit DACs, and RTC Pin Description MAX1407 MAX1414 MAX1408 MAX1409 PIN 1 — — FB2 Force/Sense DAC2 Feedback Input — 1 — IN7 Analog Input. Analog input to the negative mux only. — — 1 FB1 Force/Sense DAC1 Feedback Input 2 2 — D0 Digital Output. Three-state general-purpose digital output. 3 — — FB1 Force/Sense DAC1 Feedback Input — 3 — IN6 Analog Input.
Low-Power, 16-Bit Multichannel DAS with Internal Reference,10-Bit DACs, and RTC MAX1407 MAX1414 MAX1408 MAX1409 PIN FUNCTION 20 20 14 INT Active-Low Interrupt Output. INT goes low when the PLL output is ready, when the signal-detect comparator is tripped, or when the alarm is triggered. 21 21 15 DOUT 22 22 16 DIN 23 23 17 SCLK 24 24 18 CS 25 25 19 DGND Digital Ground. Reference point for digital circuitry.
MAX1407/MAX1408/MAX1409/MAX1414 Low-Power, 16-Bit Multichannel DAS with Internal Reference,10-Bit DACs, and RTC AVDD CS SCLK DIN DOUT CPLL SERIAL INTERFACE FOUT CLKIN CLKOUT 2.4576MHz PLL 32.768kHz OSCILLATOR DVDD RTC AND ALARM WU2 WAKE-UP LOGIC WU1 SHDN MAX1407/MAX1414 IN3 IN2 IN1 IN0 OUT2 OUT1 INTERRUPT GENERATOR COMPARATOR 8:1 INPUT MUX BUF REF AVDD PGA 16-BIT ADC DIGITAL OUTPUT INT DRDY D0 BUF FB2 FB1 IN3 IN2 IN1 IN0 REF AGND 8:1 INPUT MUX 1.8V/2.7V µP SUPERVISORS 1.
Low-Power, 16-Bit Multichannel DAS with Internal Reference,10-Bit DACs, and RTC CS SCLK DIN DOUT SERIAL INTERFACE CPLL FOUT CLKIN CLKOUT DVDD 32.768kHz OSCILLATOR 2.4576MHz PLL MAX1407/MAX1408/MAX1409/MAX1414 AVDD RTC AND ALARM WU2 WAKE-UP LOGIC WU1 SHDN IN5 IN4 IN3 IN2 IN1 IN0 INTERRUPT GENERATOR COMPARATOR 8:1 INPUT MUX BUF REF AVDD DIGITAL OUTPUT 16-BIT ADC PGA INT DRDY D0 BUF IN7 IN6 IN3 IN2 IN1 IN0 REF AGND 8:1 INPUT MUX 1.8V/2.7V µP SUPERVISORS 1.
MAX1407/MAX1408/MAX1409/MAX1414 Low-Power, 16-Bit Multichannel DAS with Internal Reference,10-Bit DACs, and RTC LX VDD = 3.3V OR VBAT OUT RST 10µF LX 18nF MAX1833 SHDN BATT CPLL GND 0.1µF AVDD VDD µP/µC CLKIN REF 4.7µF RESET RESET IN0 10µF 0.1µF DVDD SHDN VBAT 0.1µF 32.768kHz RL CLKOUT IN1 RT MAX1407 MAX1414 FOUT CLKIN CS SCLK OUTPUT DOUT SCK MOSI MISO INT INPUT DRDY INPUT DIN OUT1 RF FB1 SENSOR WE RE CE FB2 WU1 I/O WU2 I/O OUT2 AGND VSS DGND Figure 4.
Low-Power, 16-Bit Multichannel DAS with Internal Reference,10-Bit DACs, and RTC REXT CEXT RMUX CPIN RSW CST CSAMPLE CC Figure 6. Analog Input—Unbuffered Mode Unbuffered Mode When used in unbuffered mode, the switched capacitor sampling front end of the modulator presents a dynamic load to the driving circuitry. The size of the internal sampling capacitor and the input sampling frequency (Figure 6) determines the dynamic load (see Dynamic Input Impedance section).
0 -20 -40 GAIN (dB) MAX1407/MAX1408/MAX1409/MAX1414 Low-Power, 16-Bit Multichannel DAS with Internal Reference,10-Bit DACs, and RTC -60 -80 -100 -120 -140 -160 0 20 40 60 80 100 120 140 160 180 200 FREQUENCY (Hz) Figure 7. Frequency Response of the SINC3 Filter (Notch at 60Hz) Figure 7 shows the filter frequency response. The SINC3 characteristic cutoff frequency is 0.262 times the first notch frequency. This results in a cutoff frequency of 15.
Low-Power, 16-Bit Multichannel DAS with Internal Reference,10-Bit DACs, and RTC Crystal Oscillator The on-chip oscillator requires an external crystal (or resonator) connected between CLKIN and CLKOUT with an operating frequency of 32.768kHz. This oscillator is used for the RTC, alarm, signal-detect comparator, and PLL. The oscillator is operational down to 1.8V. In any crystal-based oscillator circuit, the oscillator frequency is based on the characteristics of the crystal.
MAX1407/MAX1408/MAX1409/MAX1414 Low-Power, 16-Bit Multichannel DAS with Internal Reference,10-Bit DACs, and RTC CS SCLK DIN 1 0 A4 A3 A2 A1 A0 x D7 D6 D5 D4 D3 D2 D1 D0 1 1 A4 A3 A2 A1 A0 x ADC CONV DOUT D15 D14 D13 D12 D11 D10 D9 D8 D7 D6 D5 D4 D3 D2 D1 D0 DRDY Figure 8.
Low-Power, 16-Bit Multichannel DAS with Internal Reference,10-Bit DACs, and RTC between writes to the MAX1407/MAX1408/MAX1409/ MAX1414. Figures 11–14 show the read and write timing for 8- and 16-bit data. Data is updated on the last rising edge of the SCLK in the command word. CS should not go high between data transfers. If CS is toggled before the end of a write or read operation, the device can enter an incorrect mode. Clock in 72 zeros to clear this state and re-arm the serial interface.
MAX1407/MAX1408/MAX1409/MAX1414 Low-Power, 16-Bit Multichannel DAS with Internal Reference,10-Bit DACs, and RTC CS SCLK DIN 1 0 A4 A3 A2 A1 A0 x D15 D14 D13 D12 D11 D10 D9 D8 D7 D6 D5 D4 D3 D2 D1 D0 D7 D6 D5 D4 D3 D2 D1 D0 DOUT Figure 11. Serial Interface 16-Bit Write Timing Diagram CS SCLK DIN 1 0 A4 A3 A2 A1 A0 x D7 D6 D5 D4 D3 D2 D1 D0 D15 D14 D13 D12 D11 D10 D9 D8 DOUT Figure 12.
Low-Power, 16-Bit Multichannel DAS with Internal Reference,10-Bit DACs, and RTC SCLK 1 DIN 1 A4 A3 A2 A1 A0 x D7 DOUT D6 D5 D4 D3 D2 D1 D0 Figure 14. Serial Interface 8-Bit Read Timing Diagram Table 2.
MAX1407/MAX1408/MAX1409/MAX1414 Low-Power, 16-Bit Multichannel DAS with Internal Reference,10-Bit DACs, and RTC On-Chip Registers ADC REGISTER (00000) FIRST BIT (MSB) NAME DEFAULTS (LSB) MODE RATE GAIN1 GAIN0 BUFP BUFN BIP STA1 0 0 0 0 0 0 0 0 MODE: Conversion Mode bit. A logic zero selects a normal ADC conversion, while a logic 1 selects an offset calibration conversion. After completing a calibration conversion, MODE automatically resets to zero. RATE: Conversion Rate bit.
Low-Power, 16-Bit Multichannel DAS with Internal Reference,10-Bit DACs, and RTC POSITIVE MUX INPUT MUXP2 MUXP1 MUXP0 MAX1407/MAX1414 MAX1408 MAX1409 AVDD AVDD AVDD 0 0 0 REF REF REF 0 0 1 OUT1 IN4 OUT1 0 1 0 IN0 IN0 IN0 0 1 1 IN1 IN1 — 1 0 0 IN2 IN2 — 1 0 1 IN3 IN3 — 1 1 0 OUT2 IN5 — 1 1 1 MUXN2 MUXN1 MUXN0 Table 5.
MAX1407/MAX1408/MAX1409/MAX1414 Low-Power, 16-Bit Multichannel DAS with Internal Reference,10-Bit DACs, and RTC OFFSET REGISTER (00011) FIRST BIT (MSB) OFF15 OFF14 OFF13 OFF12 OFF11 OFF10 OFF9 OFF8 OFF7 OFF6 OFF5 OFF4 OFF3 OFF2 OFF1 OFF0 (LSB) The Offset register contains the 16-bit result from the most recently completed ADC offset calibration. The data format is two’s complement and is subtracted from the filter output before writing to the Data register.
Low-Power, 16-Bit Multichannel DAS with Internal Reference,10-Bit DACs, and RTC FIRST BIT (MSB) NAME DEFAULT (LSB) WU2 WU1 RST LVD SDC CLK ADD — 0 0 1 1 0 0 0 0 WU2: Wake-Up2 status bit. When WU2 is pulled low, WU2 is set to a logic 1. Reading the Status register clears WU2, unless WU2 is still low. When WU2 is pulled low when the device is awake (not in Sleep mode), WU2 is cleared. WU1: Wake-Up1 status bit. When WU1 is pulled low, WU1 is set to a logic 1.
MAX1407/MAX1408/MAX1409/MAX1414 Low-Power, 16-Bit Multichannel DAS with Internal Reference,10-Bit DACs, and RTC Table 7.
Low-Power, 16-Bit Multichannel DAS with Internal Reference,10-Bit DACs, and RTC FIRST BIT (MSB) NAME DEFAULT (LSB) M_HR 12/24 AP 10HR HR3 HR2 HR1 HR0 0 0 0 0 0 0 0 0 M_HR: Alarm mask bit. A logic 1 masks out the hour alarm comparator. 12/24: 12/24-hour mode bit. A logic 1 selects 12-hour mode while a logic 0 selects 24-hour mode. This bit must be the same as the 12/24-bit of the RTC_Hour register for correct operation. AP: AM/PM bit.
MAX1407/MAX1408/MAX1409/MAX1414 Low-Power, 16-Bit Multichannel DAS with Internal Reference,10-Bit DACs, and RTC ALARM/CLOCK_CTRL REGISTER (01110) FIRST BIT (MSB) NAME DEFAULT (LSB) WE — — — — — — AE 0 0 0 0 0 0 0 0 WE: Write Enable bit. WE must be set to “1” before any write operation to the clock and the alarm register. A logic 0 disables write operations to the clock and alarm registers, including the AE bit. The WE signal takes effect after the 8th SCLK rising edge for an 8-bit write.
Low-Power, 16-Bit Multichannel DAS with Internal Reference,10-Bit DACs, and RTC FIRST BIT (MSB) (LSB) NAME — 10MIN2 10MIN1 10MIN0 MIN3 MIN2 MIN1 MIN0 DEFAULT 0 0 0 0 0 0 0 0 10MIN[2:0]: These are the 10 minute bits (0–50 minutes) of the RTC. MIN[3:0]: These are the minute bits (0–9 minutes) of the RTC. RTC_HOUR REGISTER (10010) FIRST BIT (MSB) (LSB) NAME — 12/24 AP 10HR HR3 HR2 HR1 HR0 DEFAULT 0 0 0 0 0 0 0 0 AP: AM/PM-bit.
MAX1407/MAX1408/MAX1409/MAX1414 Low-Power, 16-Bit Multichannel DAS with Internal Reference,10-Bit DACs, and RTC 10MO: This is the 10 month bit (10–12 months) JAN 01h JUL 07h MONTH 10MO MO[3:0] MONTH 10MO MO[3:0] MO[3:0]: These are the month bits (0–9 months) for the RTC. The following table is the Hex code for the twelve months of the year.
Low-Power, 16-Bit Multichannel DAS with Internal Reference,10-Bit DACs, and RTC CIRCUIT BLOCK BIT INITIAL POWER-UP SLEEP STANDBY IDLE RUN WAKE-UP EVENT 32kHz Oscillator CH 0 (oscillator is on) N/A N/A N/A N/A N/A RTC CH 0 (RTC is on) N/A N/A N/A N/A N/A Low VDD Voltage Monitor (2.7V) LVDE 1 (2.7V monitor is on) 1 if VM = 0 0 if VM = 1 1 1 1 1 RESET Voltage Monitor (1.8V) LSDE 0 (1.
MAX1407/MAX1408/MAX1409/MAX1414 Low-Power, 16-Bit Multichannel DAS with Internal Reference,10-Bit DACs, and RTC DA1E: DAC1 Power Enable. A logic 1 powers DAC1, while a logic 0 powers it down. The output buffer goes high impedance in power-down mode. DA2E: DAC2 Power Enable. A logic 1 powers DAC2, while a logic 0 powers it down. The output buffer goes high impedance in power-down mode.
Low-Power, 16-Bit Multichannel DAS with Internal Reference,10-Bit DACs, and RTC Alarm and RTC Programming Three write operations are needed for every update of the ALARM and RTC registers. First set the WE bit of the Alarm/Clock_CTRL Register to 1. Update the Alarm, RTC, and Alarm/Clock_CTRL Register with the new values, and then set the WE bit back to 0. This will avoid collisions in setting the time. Power-On Reset or Power-Up At initial power-up, the MAX1407/MAX1408/MAX1409/ MAX1414 are in Standby mode.
MAX1407/MAX1408/MAX1409/MAX1414 Low-Power, 16-Bit Multichannel DAS with Internal Reference,10-Bit DACs, and RTC 4 AVDD 3 2.7V 2 1 0v RESET (OPEN-DRAIN) HI tDSLP LO HI 32kHz CLOCK LO HI WU1,WU2 (INT. PULLUP) tWU LO tDPU HI SHDN LO tDPD tDFON FOUT (2.4576MHz) tDFON HI LO tDFOF tDFI tDFI HI INT LO HI DRDY LO HI DOUT LO THREE-STATED HI SLEEP WRITE CS LO SCLK, DIN HI LO INITIAL POWER-UP SLEEP MODE WAKE-UP Figure 15. Initial Power-up, Sleep Mode, and Wake-Up Timing Diagram with AVDD >2.
Low-Power, 16-Bit Multichannel DAS with Internal Reference,10-Bit DACs, and RTC POWER MODES CIRCUIT BLOCKS SLEEP STANDBY IDLE RUN WAKE-UP EVENT Serial Interface x x x x x Wake-Up Circuitry x x x x x Crystal Oscillator x x x x x RTC with Alarm x x x x x RESET Voltage Monitor x x x x x Low VDD Voltage Monitor — x x x x Master Bias Circuit — x x x x PLL — x x x x FOUT — x x x x SHDN = High — x x x x DAC1 — — x x N/A DAC2 — — x x N/A
MAX1407/MAX1408/MAX1409/MAX1414 Low-Power, 16-Bit Multichannel DAS with Internal Reference,10-Bit DACs, and RTC R1 R2 REF MAX1407/MAX1409/MAX1414 FB1 FB_ DAC 1 +5V VOUT OUT1 DAC_ OUT_ -5V REF FB2 R2 = R1 MAX1407/MAX1409/MAX1414 DAC 2 OUT2 AGND Figure 18. Bipolar Output Circuit DGND will keep doing conversions at a rate of 30Hz until powered down. THE MAX1409 HAS ONE DAC VREF = 1.
Low-Power, 16-Bit Multichannel DAS with Internal Reference,10-Bit DACs, and RTC DAC CONTENTS MSB DAC CONTENTS ANALOG OUTPUT LSB MSB ANALOG OUTPUT LSB 1111 1111 11 +VREF(1023/1024) 1111 1111 11 +VREF (511/512) 1000 0000 01 +VREF (513/1024) 1000 0000 01 +VREF (1/512) 1000 0000 00 +VREF (512/1024) = +VREF/2 1000 0000 00 0 0111 1111 11 +VREF (511/1024) 0111 1111 11 -VREF (1/512) 0000 0000 01 +VREF (1/1024) 0000 0000 01 -VREF (511/512) 0000 0000 00 0 0000 0000 00 -VREF (512/512) = -
MAX1407/MAX1408/MAX1409/MAX1414 Low-Power, 16-Bit Multichannel DAS with Internal Reference,10-Bit DACs, and RTC 100µH V+ VDD (+3.3V) LX MAX640 SHDN D1 100µF 18nF 0.1µF 0.1µF 0.1µF VOUT LBI VFB CPLL GND MAX1407 MAX1408 MAX1409 MAX1414 2R IN0 VBAT DVDD AVDD VDD RESET RESET WU1 INPUT µP/µC R E1* AGND 33µF DGND VSS *ONE TRANSISTOR (9V), ONE J CELL (6V), OR FOUR ALKALINE CELLS Figure 21. Power-Supply Circuit Using MAX640 Step-Down DC-DC Converter VBAT E1* 10µF 18nF CPLL 0.
Low-Power, 16-Bit Multichannel DAS with Internal Reference,10-Bit DACs, and RTC MAX1407 MAX1414 REF OUT1 10-BIT DAC REF OUT1 10-BIT DAC IF RF FB1 AUX. VOLTAGE INPUTS MAX1407/MAX1408/MAX1409/MAX1414 MAX1407 MAX1409 MAX1414 IN0 IN1 IN2 IN3 IN0 IN1 IN2 IN3 AUX. VOLTAGE INPUTS WE SENSOR CE IF RF FB1 WE SENSOR CE REF OUT2 10-BIT DAC FB2 BAND GAP BUF REF BAND GAP 4.7µF ALL I/O AVAILABLE AS INPUTS TO ADC AND COMPARATOR. MAX1409 HAS IN0, OUT1, FB1, AND REF ONLY. REF BUF 4.
MAX1407/MAX1408/MAX1409/MAX1414 Low-Power, 16-Bit Multichannel DAS with Internal Reference,10-Bit DACs, and RTC REF RL REF IN0 8:1 MUX 16b ADC DRDY RT AGND 8:1 MUX INTERRUPT GENERATOR CMP INT WAKE-UP MAX1407 MAX1408 MAX1409 MAX1414 BAND GAP REF BUF 4.7µF DRDY NOT AVAILABLE ON THE MAX1409 Figure 27. Thermistor Application Circuit CJC THERMOCOUPLE JUNCTION REF IN0 8:1 MUX R C IN1 DRDY AGND R C IN2 REF 16b ADC 8:1 MUX INTERRUPT GENERATOR CMP INT WAKE-UP BUF BAND GAP 4.
Low-Power, 16-Bit Multichannel DAS with Internal Reference,10-Bit DACs, and RTC REF RA IN0 RB 8:1 MUX 16-BIT ADC DRDY RD IN1 RC 8:1 MUX INTERRUPT GENERATOR CMP INT WAKE-UP MAX1407 MAX1408 MAX1414 BAND GAP BUF REF 4.7µF DRDY NOT AVAILABLE ON THE MAX1409 Figure 29. Strain-Gauge Application Circuit Thermocouple Measurement Figure 28 shows a thermocouple connected to the differential inputs of the MAX1407/MAX1408/MAX1409/ MAX1414.
MAX1407/MAX1408/MAX1409/MAX1414 Low-Power, 16-Bit Multichannel DAS with Internal Reference,10-Bit DACs, and RTC the placement of the crystal on the PC board layout to insure that extra clock “ticks” do not couple onto the crystal pins. 1) It is important to place the crystal as close as possible to the CLKIN and CLKOUT pins. Keeping the trace lengths between the crystal and pins as small as possible reduces the probability of noise coupling by reducing the length of the “antennae”.
Low-Power, 16-Bit Multichannel DAS with Internal Reference,10-Bit DACs, and RTC LX OUT RST DC-DC CONVERTER SHDN BATT CPLL GND AVDD DVDD SHDN VDD RESET IN0 RESET µP/µC CLKIN REF VBAT CLKOUT IN1 MAX1407 MAX1414 OUT1 FOUT CLKIN CS SCLK OUTPUT DIN SCK MOSI DOUT MISO INT INPUT DRDY INPUT FB1 SENSOR WE RE CE FB2 WU1 I/O WU2 I/O OUT2 AGND DGND VSS ______________________________________________________________________________________ 47 MAX1407/MAX1408/MAX1409/MAX1414 Typical
Low-Power, 16-Bit Multichannel DAS with Internal Reference,10-Bit DACs, and RTC SSOP.EPS MAX1407/MAX1408/MAX1409/MAX1414 Package Information Maxim cannot assume responsibility for use of any circuitry other than circuitry entirely embodied in a Maxim product. No circuit patent licenses are implied. Maxim reserves the right to change the circuitry and specifications without notice at any time.