A3PE3000L-1FG484I Datasheet, PDF (20/242 Pages) Microsemi Corporation – ProASIC3L Low Power Flash FPGAs with Flash*Freeze Technology

ProASIC3L DC and Switching Characteristics
PLL Behavior at Brownout Condition
Microsemi recommends using monotonic power supplies or voltage regulators to ensure proper powerup
behavior. Power ramp-up should be monotonic at least until VCC and VCCPLX exceed brownout
activation levels. The VCC activation level is specified as 1.1 V worst-case (see Figure 2-1 and Figure 2-
2 on page 2-5 for more details).
When PLL power supply voltage and/or VCC levels drop below the VCC brownout levels (0.75 V ± 0.25
V), the PLL output lock signal goes low and/or the output clock is lost. Refer to the "Power-Up/-Down
Behavior of Low-Power Flash Devices" chapter of the ProASIC3L FPGA Fabric User’s Guide for
information on clock and lock recovery.
Internal Power-Up Activation Sequence
1. Core
2. Input buffers
Output buffers, after 200 ns delay from input buffer activation.
VCC
VCC = 1.575 V
VCC = 1.425 V
Activation trip point:
V_a = 0.85 V ± 0.25 V
Deactivation trip point:
V_d = 0.75 V ± 0.25 V
VCC = VCCI + VT
where VT can be from 0.58 V to 0.9 V (typically 0.75 V)
Region 1: I/O Buffers are OFF
Region 4: I/O
buffers are ON.
I/Os are functional
(except differential
but slower because VCCI
is below specification. For the
same reason, input buffers do not
meet VIH / VIL levels, and output
buffers do not meet VOH / VOL levels.
Region 5: I/O buffers are ON
and power supplies are within
specification.
I/Os meet the entire datasheet
and timer specifications for
speed, VIH / VIL, VOH / VOL,
etc.
Region 2: I/O buffers are ON.
I/Os are functional (except differential inputs)
but slower because VCCI / VCC are below
specification. For the same reason, input
buffers do not meet VIH / VIL levels, and
output buffers do not meet VOH / VOL levels.
Region 3: I/O buffers are ON.
I/Os are functional; I/O DC
specifications are met,
but I/Os are slower because
the VCC is below specification.
Region 1: I/O buffers are OFF
Activation trip point:
V_a = 0.9 V ± 0.3 V
Deactivation trip point:
V_d = 0.8 V ± 0.3 V
Min VCCI datasheet specification
voltage at a selected I/O
standard; i.e., 1.425 V or 1.7 V
or 2.3 V or 3.0 V
Figure 2-1 • V5 Devices – I/O State as a Function of VCCI and VCC Voltage Levels
VCCI
2-4
Revision 13