Rainbow Electronics AT91CAP9S250A - Manual (Page 967)

967
6264A–CAP–21-May-07
AT91CAP9S500A/AT91CAP9S250A
47.9 ADC
Notes: 1. Corresponds to 13 clock cycles at 5 MHz: 3 clock cycles for track and hold acquisition time and 10 clock cycles for
conversion.
The user can drive ADC input with impedance up to:
• Z
OUT
≤
(SHTIM -500) x 12.5
with SHTIM (Sample and Hold Time register) expressed in ns and Z
OUT
expressed in ohms.
Table 47-14. Channel Conversion Time and ADC CLock
Parameter Conditions Min Typ Max Units
ADC Clock Frequency 10-bit resolution mode 5 MHz
ADC Clock Frequency 8-bit resolution mode TBD MHz
Startup Time Return from Idle Mode 40 µs
Track and Hold Acquisition Time 500 ns
Conversion Time ADC Clock = 5 MHz 2 µs
Throughput Rate ADC Clock = 5 MHz 384 (1) kSPS
Table 47-15. External Voltage Reference Input
Parameter Conditions Min Typ Max Units
ADVREF Input Voltage Range 2.6 VDDANA V
ADVREF Average Current On 13 samples with ADC Clock = 5 MHz 250 µA
Current Consumption on VDDANA 300 µA
Table 47-16. Analog Inputs
Parameter Min Typ Max Units
Input Voltage Range 0 ADVREF
Input Leakage Current 1 µA
Input Capacitance 5 pF
Table 47-17. Transfer Characteristics
Parameter Min Typ Max Units
Resolution 10 Bit
Integral Non-linearity ±2 LSB
Differential Non-linearity ±0.9 LSB
Offset Error -1.5 0.5 2.5 LSB
Gain Error ±2 LSB