EPM2210F100A ALTERA [Altera Corporation], EPM2210F100A Datasheet - Page 55

• Manufacturer Part Number: EPM2210F100A
• Description: MAX II Device Family
• Manufacturer: ALTERA [Altera Corporation]

Chapter 4: Hot Socketing and Power-On Reset in MAX II Devices
Power-On Reset Circuitry
Figure 4–4. ESD Protection During Negative Voltage Zap
Power-On Reset Circuitry
© October 2008 Altera Corporation
When the I/O pin receives a negative ESD zap at the pin that is less than –0.7 V (0.7 V
is the voltage drop across a diode), the intrinsic
P-Substrate/N+ drain diode is forward biased. Therefore, the discharge ESD current
path is from GND to the I/O pin, as shown in
MAX II devices have POR circuits to monitor V
power-up. The POR circuit monitors these voltages, triggering download from the
non-volatile configuration flash memory (CFM) block to the SRAM logic, maintaining
tri-state of the I/O pins (with weak pull-up resistors enabled) before and during this
process. When the MAX II device enters user mode, the POR circuit releases the I/O
pins to user functionality. The POR circuit of the MAX II (except MAX IIZ) device
continues to monitor the V
POR circuit of the MAX IIZ device does not monitor the V
device enters into user mode. More details are provided in the following sub-sections.
I/O
GND
Source
Drain
Drain
Source
CCINT
PMOS
NMOS
voltage level to detect a brown-out condition. The
Gate
Gate
P-Substrate
Figure
CCINT
N+
N+
and V
D
S
4–4.
GND
I/O
G
CCIO
CCINT
voltage levels during
voltage level after the
MAX II Device Handbook
4–5