标题: TC500/500A/510/514 dataSheet [打印本页] 作者: admin 时间: 2010-4-17 17:30 标题: TC500/500A/510/514 dataSheet Precision Analog Front Ends with Dual Slope ADC
The TC500/500A/510/514 family are precision analog front ends that implement dual slope A/D converters having a maximum resolution of 17 bits plus sign.As a minimum, each device contains the integrator,zero crossing comparator and processor interface logic.The TC500 is the base (16 bit max)device and requires both positive and negative power supplies.The TC500A is identical to the TC500, except it has improved linearity allowing it to operate to a maximum resolution of 17 bits.The TC510 adds an onboard negative power supply converter for single supply operation.The TC514 adds both a negative power supply converter and a 4 input differential analog multiplexer. Each device has the same processor control interface consisting of 3 wires:control inputs A and B and zero-crossing comparator output (CMPTR).The processor manipulates A,B to sequence the TC5xx through four phases of conversion:Auto Zero,Integrate,Deintegrate and Integrator Zero.During the Auto Zero phase,offset voltages in the TC5xx are corrected by a closed-loop feedback mechanism.The input voltage is applied to the integrator during the Integrate phase.This causes an integrator output dv/dt directly proportional to the magnitude of the input voltage. The higher the input voltage,the greater the magnitude of the voltage stored on the integrator during this phase. At the start of the Deintegrate phase,an external voltage reference is applied to the integrator,and at the same time,the external host processor starts its on-board timer.The processor maintains this state until a transition occurs on the CMPTR output,at which time the processor halts its timer. The resulting timer count is the converted analog data.Integrator Zero (the final phase of conversion)removes any residue remaining in the integrator in preparation for the next conversion. The TC500/500A/510/514 offer high resolution (up to 17 bits)superior 50Hz/60Hz noise rejection,low power operation, minimum I/O connections, low input bias currents and lower cost compared to other converter technologies having similar conversion speeds.
Parameter Name Value
Input Voltage Range (V) Vss +1.5V to Vdd -1.5V
Sampling Rate 4 to 10
Programmable resolution/conversion time Yes
Input Range Yes
Input Channels 1
Charge pump (-V) output pin No
Resolution Up to 16 bits
Sampling Rate (Conv/sec) 4 to 10
Interface 3-wire
Supply Voltage Min (V) ±4.5
Supply Voltage Max (V) ±7.5
Features
Precision (up to 17 Bits)
A/D Converter "Front End"
3-Pin Control Interface to Microprocessor
Flexible: User Can Trade-Off Conversion Speed for Resolution
Single Supply Operation (TC510/514)
4 Input, Differential Analog MUX (TC514)
Automatic Input Voltage Polarity Detection
Low Power Dissipation .... TC500/500A: 10mW TC510/514: 18mW
Wide Analog Input Range ............................ ±4.2V (TC500A/510)
Directly Accepts Bipolar and Differential Input Signals
