M1AFS600-PQ208 Datasheet, PDF (105/334 Pages) Microsemi Corporation – Fusion Family of Mixed Signal FPGAs

Fusion Family of Mixed Signal FPGAs
Current Monitor
The Fusion Analog Quad is an excellent element for voltage- and current-monitoring applications. In
addition to supporting the same functionality offered by the AV pad, the AC pad can be configured to
monitor current across an external sense resistor (Figure 2-70). To support this current monitor function,
a differential amplifier with 10x gain passes the amplified voltage drop between the AV and AC pads to
the ADC. The amplifier enables the user to use very small resistor values, thereby limiting any impact on
the circuit. This function of the AC pad does not limit AV pad operation. The AV pad can still be
configured for use as a direct voltage input or scaled through the AV prescaler independently of it’s use
as an input to the AC pad’s differential amplifier.
Power
Off-Chip
Pads
On-Chip
AV
Voltage
Monitor Block
Prescaler
AC
Current
Monitor Block
AG
Gate
Driver
AT
Temperature
Monitor Block
Analog Quad
Prescaler
Prescaler
Digital
Input
Digital
Input
Current
Monitor / Instr
Amplifier
Power
MOSFET
Gate Driver
To FPGA
(DAVOUTx)
To Analog MUX
To FPGA
(DACOUTx)
From FPGA
(GDONx)
To Analog MUX
Figure 2-70 • Analog Quad Current Monitor Configuration
Digital
Input
Temperature
Monitor
To FPGA
(DATOUTx)
To Analog MUX
Revision 4
2- 89