Datasheet

Data Sheet ADAS1000-3/ADAS1000-4
Rev. A | Page 15 of 76
Table 9. Pin Function Descriptions
ADAS1000-3 Pin No. ADAS1000-4 Pin No.
Mnemonic Description
LQFP LFCSP LQFP LFCSP
18, 23,
58, 63
15, 20,
51, 56
18, 23, 58,
63
15, 20, 51,
56
AVDD
Analog Supply. See recommendations for bypass capacitors in the
Power Supply,
Grounding, and Decoupling Strategy
section.
35, 46 30, 41 35, 46 30, 41 IOVDD Digital Supply for Digital Input/Output Voltage Levels. See recommendations for
bypass capacitors in the
Power Supply, Grounding, and Decoupling Strategy
section.
26, 55 23, 48 26, 55 23, 48 ADCVDD Analog Supply for ADC. There is an on-chip linear regulator providing the supply
voltage for the ADCs. These pins are primarily provided for decoupling purposes;
however, the pin may also be supplied by an external 1.8 V supply should the user wish
to use a more efficient supply to minimize power dissipation. In this case, use the
VREG_EN pin tied to ground to disable the ADCVDD and DVDD regulators. The
ADCVDD pin should not be used to supply other functions. See recommendations for
bypass capacitors in the
Power Supply, Grounding, and Decoupling Strategy
section.
30, 51 27, 44 30, 51 27, 44 DVDD Digital Supply. There is an on-chip linear regulator providing the supply voltage for the
digital core. These pins are primarily provided for decoupling purposes; however, the
pin may also be overdriven supplied by an external 1.8 V supply should the user wish to
use a more efficient supply to minimize power dissipation. In this case, use the
VREG_EN pin tied to ground to disable the ADCVDD and DVDD regulators. See
recommendations for bypass capacitors in the
Power Supply, Grounding, and
Decoupling Strategy
section.
2, 15, 24,
25, 56, 57
1, 14, 21,
22, 49, 50
2, 15, 24,
25, 56, 57
1, 14, 21,
22, 49, 50
AGND Analog Ground.
31, 34,
40, 47, 50
28, 29,
36, 42, 43
31, 34, 40,
47, 50
28, 29, 36,
42, 43
DGND Digital Ground.
59 19 59 19 VREG_EN Enables or disables the internal voltage regulators used for ADCVDD and DVDD. Tie this
pin to AVDD to enable or tie this pin to ground to disable the internal voltage
regulators.
10 6 10 6 ECG1_LA Analog Input, Left Arm (LA).
11 5 11 5 ECG2_LL Analog Input, Left Leg (LL).
12 4 12 4 ECG3_RA Analog Input, Right Arm (RA).
4 12 EXT_RESP_RA Optional External Respiration Input.
5 11 EXT_RESP_LL Optional External Respiration Input.
6 10 EXT_RESP_LA Optional External Respiration Input.
62 16 RESPDAC_LL Optional Path for Higher Performance Respiration Resolution, Respiration DAC Drive,
Negative Side 0.
60 18 SHIELD/
RESPDAC_LA
Shared Pin (User-Configured).
Output of Shield Driver (SHIELD).
Optional Path for Higher Performance Respiration Resolution, Respiration DAC Drive,
Negative Side 1 (RESPDAC_LA).
60 18 SHIELD Output of Shield Driver.
3 13 RESPDAC_RA Optional Path for Higher Performance Respiration Resolution, Respiration DAC Drive,
Positive Side.
22 52 22 52 CM_OUT/WCT Common-Mode Output Voltage (Average of Selected Electrodes). Not intended to drive
current.
19 55 19 55 CM_IN Common-Mode Input.
21 53 21 53 RLD_SJ Summing Junction for Right Leg Drive Amplifier.
20 54 20 54 RLD_OUT Output and Feedback Junction for Right Leg Drive Amplifier.
61 17 61 17 CAL_DAC_IO Calibration DAC Input/Output. Output for a master device, input for a slave. Not
intended to drive current.
9 7 9 7 REFIN Reference Input. For standalone mode, use REFOUT connected to REFIN. External 10 μF
capacitors with ESR < 0.2 Ω in parallel with 0.1 μF bypass capacitors to GND are
required and should be placed as close to the pin as possible. An external reference can
be connected to REFIN.
8 8 8 8 REFOUT Reference Output.
7 9 7 9 REFGND Reference Ground. Connect to a clean ground.
27, 28 47, 46 27, 28 47, 46 XTAL1, XTAL2 External crystal connects between these two pins; external clock drive should be
applied to CLK_IO. Each XTAL pin requires a 15 pF capacitor to ground.
29 45 29 45 CLK_IO Buffered Clock Input/Output. Output for a master device; input for a slave. Powers up in
high impedance.
41 35 41 35
CS
Chip Select and Frame Sync, Active Low.
CS
can be used to frame each word or to frame
the entire suite of data in framing mode.