12-Bit A/D Converter (Adc12A); Overview - Epson S1C17M20 Technical Manual

19 12-bit A/D Converter (ADC12A)

19.1 Overview

The ADC12A is a successive approximation type 12-bit A/D converter.
The features of the ADC12A are listed below.
• Conversion method:
• Resolution:
• Analog input voltage range:
• Supports two conversion modes:
• Supports three conversion triggers: 1. Software trigger
• Can convert multiple analog input signals sequentially.
• Can generate conversion completion and overwrite error interrupts.
Figure 19.1.1 shows the ADC12A configuration.
Table 19.1.1 ADC12A Configuration of S1C17M20/M21/M22/M23/M24/M25
Item
Number of channels
Number of analog signal inputs
per channel
16-bit timer used as conversion
clock and trigger sources
Clock
Timer
generator
16-bit timer
Ch.k
CLK_T16_k
Interrupt
controller
Note: In this chapter, n, m, and k refer to an ADC12A channel number, an analog input pin number, and
a 16-bit timer channel number, respectively.
S1C17M20/M21/M22/M23/M24/M25
TECHNICAL MANUAL (Rev. 1.0)
Successive approximation type
12 bits
Reference voltage VREFA to V
1. One-time conversion mode
2. Continuous conversion mode
2. 16-bit timer underflow trigger
3. External trigger
S1C17M20/M23
24-pin package
Ch.0: 4 inputs
(ADIN00–ADIN03)
Underflow
CNVMD Trigger
CNVTRG[1:0] select circuit
MODEN
ADSTAT[2:0]
BSYSTAT
Successive
approximation
AD0D[15:0] control circuit
AD1D[15:0]
ADmD[15:0]
AD0CIF
AD1CIF
ADmCIF Interrupt
control
AD0OVIF
circuit
AD1OVIF
ADmOVIF
Figure 19.1.1 ADC12A Configuration
Seiko Epson Corporation
19 12-BIT A/D CONVERTER (ADC12A)
SS
S1C17M21/M24
32-pin package
1 channel (Ch.0)
Ch.0: 6 inputs
(ADIN00–ADIN05)
Ch.0 ← 16-bit timer Ch.3
ADST
STMD
SMPCLK[2:0]
VRANGE[1:0]
+
Comparator with
sample & hold circuit
–
D/A
converter
AD0CIE
AD1CIE
ADmCIE
AD0OVIE
AD1OVIE
ADmOVIE
S1C17M22/M25
Ch.0: 8 inputs
(ADIN00–ADIN07)
ADC12A Ch.n
#ADTRGn
ADINn0
ADINn1
MUX
ADINnm
VREFAn
19-1