AS8510 Data Acquisition Device for Battery Sensors Option for multiplexing either one differential input, or two single 1 General Description ended inputs or the internal temperature sensor on one channel The AS8510 is a virtually offset free, low noise, two channel Programmable current source for external temperature sensor measurement device. It is tailored to accurately measure battery connectable to any of the inputs current from mA range up to kA range in conjunction with a 100 High precision and high stability 1.2V reference voltage source shunt resistor in series with the battery rail. Through the second measurement channel it enables capture of, either battery voltage Digital signal processing with filter options for both channels synchronous with the current measurement, or, measure the analog Four operating modes providing output of an internal or external temperature sensor. Both channels - Continuous data acquisition (or) are matched and can either measure small signals up to 160 mV - Periodic single-shot acquisition, (or) versus ground, through programmable gain amplifier or larger - Continuous acquisition on threshold crossing of programmed signals in the 0 to 1V range without the amplifier. current levels (or) After analog to digital conversion and digital filtering, the resulting - A combination of the above 16-bit digital words are accessible through 4-wire standard serial On chip high-precision 4MHz RC oscillator or option for external interface.The device includes a number of additional features clock explained in the next section. -40C to +125C ambient operation 2 Key Features AEC - Q100 automotive qualified 3.3V supply voltage Internal chip ID for full traceability Two High resolution 16 bit A/D converters SSOP-20 pin package Programmable sampling to enable data throughputs from less than 1Hz to 8kHz 3 Applications Zero Offset for both channels The AS8510 is ideal for shunt based batteries sensor. For high-side Independent control of data rate on both channels current sensing, the input signal may be conditioned using ams device AS8525 before applying to this device. Precision, low noise, programmable gain amplifiers for both channels with gains 5, 25, 40, 100 to support wide dynamic ranges. Figure 1. AS8510 Block Diagram REF DVDD AVDD Internal Temperature Sensor Bandgap Reference Oscillators Prog-Cur ETR Source ETS MUX and PGA 16-bit Sigma-Delta ADC VBAT IN Chopper MEN VBAT GND CHOP CLK FIR / MA AS8510 INT CLK RSHH Chopper PGA 16-bit Sigma-Delta ADC RSHL Analog Common Mode Serial Interface AVSS VCM SCLK CS SDI SDO DVSS www.ams.com/AS8510 Revision 3.8 1 - 48AS8510 Datasheet - Contents Contents 1 General Description ...................................................................................................................................................................... 1 2 Key Features................................................................................................................................................................................. 1 3 Applications................................................................................................................................................................................... 1 4 Pin Assignments ........................................................................................................................................................................... 4 4.1 Pin Descriptions........................................................................................................................................................................................ 4 5 Absolute Maximum Ratings .......................................................................................................................................................... 6 6 Electrical Characteristics............................................................................................................................................................... 7 6.1 Operating Conditions................................................................................................................................................................................ 7 6.2 DC/AC Characteristics for Digital Inputs and Outputs .............................................................................................................................. 7 6.3 Detailed System and Block Specifications ............................................................................................................................................... 9 6.3.1 Electrical System Specifications .................................................................................................................................................. 9 6.4 Current Measurement Ranges (across 100Ohm shunt resistor) ........................................................................................................... 9 6.4.1 Differential Input Amplifier for Current Channel .......................................................................................................................... 10 6.4.2 Differential Input Amplifier for Voltage Channel.......................................................................................................................... 11 6.4.3 Sigma Delta Analog to Digital Converter .................................................................................................................................... 12 6.4.4 Bandgap Reference Voltage....................................................................................................................................................... 12 6.4.5 Internal (Programmable) Current Source for External Temperature Measurement ................................................................... 13 6.4.6 CMREF Circuit (VCM) ................................................................................................................................................................ 14 6.4.7 Internal AVDD Power-on Reset .................................................................................................................................................. 14 6.4.8 Internal DVDD Power-on Reset.................................................................................................................................................. 14 6.4.9 Low Speed Oscillator.................................................................................................................................................................. 14 6.4.10 High Speed Oscillator ............................................................................................................................................................... 15 6.4.11 External Clock........................................................................................................................................................................... 15 6.4.12 Internal Temperature Sensor.................................................................................................................................................... 15 6.5 System Specifications ............................................................................................................................................................................ 15 7 Detailed Description.................................................................................................................................................................... 18 7.1 Current Measurement Channel .............................................................................................................................................................. 18 7.2 Voltage/Temperature Measurement Channel ......................................................................................................................................... 18 7.3 Digital Implementation of Measurement Path......................................................................................................................................... 19 7.4 Modes of Operation................................................................................................................................................................................ 19 7.4.1 Normal Mode 1 (NOM1) ............................................................................................................................................................. 21 7.4.2 Normal Mode 2 (NOM2) ............................................................................................................................................................. 21 7.4.3 Standby Mode1 (SBM1) ............................................................................................................................................................. 22 7.4.4 Standby Mode2 (SBM2) ............................................................................................................................................................. 23 7.5 Reference-Voltage.................................................................................................................................................................................. 23 7.6 Oscillators............................................................................................................................................................................................... 23 7.7 Power-On Reset..................................................................................................................................................................................... 23 7.8 4-Wire Serial Port Interface .................................................................................................................................................................... 24 7.8.1 SPI Frame................................................................................................................................................................................... 24 7.8.2 Write Command.......................................................................................................................................................................... 25 7.8.3 Read Command.......................................................................................................................................................................... 26 7.8.4 Timing ......................................................................................................................................................................................... 27 7.8.5 SPI Interface Timing ................................................................................................................................................................... 28 www.ams.com/AS8510 Revision 3.8 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