L9803 STMicroelectronics, L9803 Datasheet - Page 70

• Manufacturer Part Number: L9803
• Description: Super Smart Power Motor Driver With 8-bit Mcu, Ram, Eeprom, Adc, Wdg, Timers, Pwm And H-bridge Driver
• Manufacturer: STMicroelectronics

On-Chip Peripherals
5.5.3
5.5.4
5.5.5
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Figure 35. Block diagram of the Analog to Digital Converter
Input Selections and Sampling
The input section of the ADC includes the analog multiplexer and a buffer. The input of the
buffer is permanently connected to the multiplexer output. The buffer output is fed to the
sample and hold circuit.
The multiplexer is driven with CH1 and CH0 bit only after ADST is set. Starting from this
event, the sampler follows the selected input signal for 2.5us and then holds it for the
remaining conversion time (i.e. when the conversion is actually running).
Interrupt Management
If ADIE bit is set in register ADCCSR, an interrupt is generated when a conversion is
completed (i.e. when COCO is set).
The interrupt request is cleared when any of the ADC registers is access (either read or
write).
Enabling/disabling the interrupt generation while the conversion is running has no effect on
the current conversion. ADIE value is latched when ADST is set and this internal value holds
all the conversion time long.
Temperature Sensing
The AD1 input is internally connected to the output of a temperature sensing circuit.
clk
8Mhz
CSR
ADST
ADIE
CH1
CH0
WR
latch
logic
d
i
v
inputs
end conversion
start conversion
DRH
DRL
M
U
X
Vin
conversion
AD0
sampling
+
.....
2 Mhz
AD9
VCC
AGND
L9803