bulk built-in current sensors (bbics) are fault detection … · 2014-11-03 · s d (1.2v) b (gnd)...
TRANSCRIPT
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Concurrent Error Detection (CED) Circuitry
Logic Block
OReg
System’s Restart
M N
OLogic
N
Reg
iste
r (F
lip-F
lops
)
Clock Clock
M
Reg
iste
r (F
lip-F
lops
) node_x
fault_flag_signal
System’s Deadlock
System’s Recovery
Options of Security Mesures
System’s Block
BBICS
IB
in = 0 out = 1 " 0
PMOS on
NMOS off
IA
PMOS-BBICS
NMOS-BBICS Flag_N = 1
Flag_P = 0
in = 1 out = 0 " 1
PMOS off
NMOS on
IB
PMOS-BBICS
NMOS-BBICS Flag_N = 0
Flag_P = 1
IA
Case 0: Case 1:
Cases of Transient Faults in an Inverter Protected by a PMOS-BBICS and a NMOS-BBICS:
Bulk Built-In Current Sensors (BBICS) are fault detection mechanisms embedded in integrated systems. BBICS are able to monitor anomalous transient currents like the so-called single event effects induced by radiation or even malicious injection sources. This work reviews BBICS principles and introduce new sensor architectures that improve the transient-fault detection sensitivity. In addition, a test chip is presented for the validation of the sensor concept under the laser-induced effects.
Transient-fault current view in a cross section of classic CMOS inverter monitored by a NMOS-BBICS:
alarm flag
C"
out ‘1’
in ‘0’
PTAP
P substrate
N well
P+
to Vdd
P+ N+ N+ P+
NMOS PMOS
NMOS_bulk
to Gnd
BBICS
Metal 1 MOS gate
N+
Test chip composed of single NMOS and PMOS transistors designed with classic and triple-well 90-nm CMOS technology.
Experiment settings: measure of laser-induced currents at λ = 1064 nm, laser spot Ø = 5 µm, pulse duration = 20 µs, 1.25 W
laser beam P substrate
N+ N+ P+
NMOS
G S D (1.2V) B (gnd)
2.5 mA
Laser-induced NMOS current Case 0
laser beam P substrate
N well
P+ P+ N+ P+
PMOS
G S B (1.2V) D (gnd) Psub bias (floating)
1.9 mA
laser beam P substrate
N well
P+ P+ N+ P+
PMOS
G S B (1.2V) D (gnd) Psub bias (gnd)
8 mA
200 µA
Bulk current that would be monitored by PMOS-BBICS
8 mA
Drain current that would contribute to produce a transient fault
200 µA
Laser-induced PMOS current Case 1A
Laser-induced PMOS current Case 1B
Bulk current monitored by a PMOS-BBICS would be an order of magnitude above drain current
N+
Pwell DNwell
Nwell Nw
ell
P substrate
N+ N+ P+
NMOS
G S D (1.2V) B (gnd) DNwell bias (floating)
laser beam
2.3 mA
N+
Pwell DNwell
Nwell Nw
ell
P substrate
N+ N+ P+
NMOS
G S D (1.2V) B (gnd) DNwell bias (1.2V)
6 mA
Bulk current that would be monitored by NMOS-BBICS
6 mA
Drain current that would contribute to create a transient fault
200 µA
laser beam
200 µA
NMOS in Pwell to mimic PMOS properties
Laser-induced NMOS current Case 0A
Laser-induced NMOS current Case 0B
Use of triple-well technology amplifies bulk current by an order of magnitude above drain current
Transistors designed with classic CMOS technology
Transistors designed with triple-well CMOS technology
Layout of 65-nm CMOS test chip with BBICS devices
Bulk current monitored by a NMOS-BBICS would have the same order of magnitude than drain current