Texas Instruments ADS1254, Руководство пользователя

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Jumpers
3-2
3.1 Jumpers
Table 3−1 shows the function of each jumper on the EVM:
Table 3−1. Jumper/Function Reference
Reference
Designator Setting Function Default Section
JMP1 1 to 2 External reference 2−3 Section 3.1.1
2 to 3 Onboard reference
JMP2 1 to 2 Digital power supplied from barrel
jack, battery, or DSK 1−2 Section 3.1.2
2 to 3 Digital power supplied from screw
terminal block J4
JMP3 1 to 2 Analog power supplied from barrel
jack, battery, or DSK 1−2 Section 3.1.2
2 to 3 Analog power supplied from screw
terminal block J4
JMP4 Connected Reference pin is connected Connected Section 3.1.3
Disconnected Reference pin is not connected
JMP5 Connected MCU controls ADS1254 Disconnected Section 3.1.4
Disconnected MCU does not control ADS1254
3.1.1 JMP1: Reference Source Select
The ADS1254EVM can use an externally supplied reference or an onboard
4.096-V zener reference (D1 and R1); use JMP1 to connect the desired
reference source. Shorting pins 1 and 2 connects the external reference;
shorting pins 2 −3 connects the onboard reference.
3.1.2 JMP2, JMP3: Power Source Select
The ADS1254 has separate analog and digital power supplies. JMP2 is used
to select the source for the digital power supply, and JMP3 is used to select
the source for the analog supply. To use the barrel jack or battery (onboard
regulator), short pins 1 −2; if you wish to use an external power supply, short
pins 2 −3.
3.1.3 JMP4: Reference Disconnect
JMP4 is used to connect an external reference directly to the ADS1254, with-
out using the onboard filtering. Removing this jumper disconnects the
ADS1254 reference pin. External reference voltage must be applied to pin 2.