XE8801AMI000WP Semtech, XE8801AMI000WP Datasheet - Page 94

• Manufacturer Part Number: XE8801AMI000WP
• Description: SENSING MACHINE WITH 16 + 10 BIT
• Manufacturer: Semtech

Specifications of XE8801AMI000WP

• Applications: Sensing Machine
• Core Processor: RISC
• Program Memory Type: FLASH (22 kB)
• Controller Series: XE8000
• Ram Size: 512 x 8
• Interface: UART, USRT
• Number Of I /o: 24
• Voltage - Supply: 2.4 V ~ 5.5 V
• Operating Temperature: -40°C ~ 85°C
• Mounting Type: Surface Mount
• Package / Case: Die
• For Use With: XE8000MP - PROG BOARD AND PROSTART2 CARD
• Other names: Q2722595

16.6
As seen in Figure 16-1, the zooming function is implemented with three programmable gain amplifiers (PGA). These
are:
•
•
•
All gain and offset settings are realized with ratios of capacitors. The user has control over each PGA activation and
gain, as well as the offset of stages 2 and 3. These functions are examined hereafter.
© Semtech 2005
PGA1: coarse gain tuning
PGA2: medium gain and offset tuning
PGA3: fine gain and offset tuning
Programmable Gain Amplifiers
PGA2_OFFSET[3:0]
PGA2_GAIN[1:0]
ENABLE[3:0]
PGA1_GAIN
Table 16-13 ADC & PGA enabling
Table 16-16 PGA2 offset settings
Table 16-14 PGA1 Gain Settings
0000
0001
0010
0011
0100
0101
1001
1010
1011
1100
1101
xxx0
xxx1
xx0x
xx1x
x0xx
x1xx
0xxx
1xxx
Table 16-15 PGA2 gain settings
00
01
10
11
0
1
16-9
PGA1 disabled
PGA2 disabled
PGA3 disabled
PGA1 enabled
PGA2 enabled
PGA3 enabled
ADC disabled
ADC enabled
PGA2 Offset
GDoff
PGA1 Gain
PGA2 Gain
GD
GD
Block
+0.2
+0.4
+0.6
+0.8
-0.2
-0.4
-0.6
-0.8
1
2
10
10
+1
-1
1
1
2
5
0
(V/V)
(V/V)
2
(V/V)
XE8801A – SX8801R
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