Datasheet

78K0/Kx2-L CHAPTER 13 OPERATIONAL AMPLIFIERS
R01UH0028EJ0400 Rev.4.00 436
Sep 27, 2010
13.3 Registers Used in Operational Amplifier
The operational amplifiers use the following four registers.
Operational amplifier 0 control register (AMP0M), operational amplifier 1 control register (AMP1M)
A/D port configuration registers 0 and 1 (ADPC0, ADPC1)
Analog input channel specification register (ADS)
Port mode registers 1, 2 (PM1, PM2)
(1) Operational amplifier 0 control register (AMP0M), operational amplifier 1 control register (AMP1M)
These registers control the operations of operational amplifiers 0 and 1.
AMP0M and AMP1M can be set by a 1-bit or 8-bit memory manipulation instruction.
Reset signal generation clears this register to 00H.
Remark Products with operational amplifier of the 78K0/KY2-L and 78K0/KA2-L:
Operational amplifier 0 is mounted.
Products with operational amplifier of the 78K0/KB2-L and 78K0/KC2-L:
Operational amplifiers 0 and 1 are mounted.
Figure 13-2. Format of Operational Amplifier 0 Control Register (AMP0M)
(Products with Operational Amplifier Only)
Address: FF60H After reset: 00H R/W
Symbol <7> <6> 5 4 3 2 1 0
AMP0M OPAMP0E PGAEN 0 0 0 0 AMP0VG1 AMP0VG0
OPAMP0E PGAEN Operational amplifier 0 operation control
0 0 Stops operational amplifier 0 operation
0 1 Enables operational amplifier 0 (PGA mode only) operation
1 0 Enables operational amplifier 0 (single AMP mode only) operation
1 1
Enables operational amplifier 0 (simultaneous operation in the PGA and single AMP
modes) operation
AMP0VG1 AMP0VG0 PGA mode of operational amplifier 0 gain selection
0 0 ¯4
0 1 ¯8
1 0 ¯16
1 1 ¯32
Cautions 1. When using the PGA mode, use the ADPC0 register to select the PGAIN/AMP0OUT/ANI1/P21 pin
as an analog I/O.
2. When using the single AMP mode, use the ADPC0 register to select the
AMP0OUT/PGAIN/ANI1/P21, AMP0-/ANI0/P20, and AMP0+/ANI2/P22 pins as analog I/O.
3. When using as digital inputs the pins of port 2, which are not used with the operational amplifier
0, when the operational amplifier 0 is used, make sure that the input levels of digital input ports
are fixed to prevent degradation of the A/D conversion resolution.
Remark The output of operational amplifier 0 is amplified by the PGA by setting OPAMP0E = PGAEN = 1.