M27C400 Datasheet, PDF (5/14 Pages) STMicroelectronics – 4 Mbit 512Kb x8 or 256Kb x16 UV EPROM and OTP EPROM

Table 7. Read Mode DC Characteristics ⁽¹⁾
(T_A = 0 to 70 °C or –40 to 85 °C; V_CC = 5V ± 5% or 5V ± 10%; V_PP = V_CC)
Symbol
Parameter
Test Condition
Min
I_LI
Input Leakage Current
I_LO Output Leakage Current
I_CC Supply Current
0V ≤ V_IN ≤ V_CC
0V ≤ V_OUT ≤ V_CC
E = V_IL, G = V_IL,
I_OUT = 0mA, f = 8MHz
E = V_IL, G = V_IL,
I_OUT = 0mA, f = 5MHz
I_CC1 Supply Current (Standby) TTL
I_CC2 Supply Current (Standby) CMOS
I_PP Program Current
E = V_IH
E > V_CC – 0.2V
V_PP = V_CC
V_IL
V_IH ⁽²⁾
Input Low Voltage
Input High Voltage
–0.3
2
V_OL Output Low Voltage
I_OL = 2.1mA
V_OH Output High Voltage TTL
I_OH = –400µA
2.4
Note: 1. V_CC must be applied simultaneously with or before V_PP and removed simultaneously or after V_PP.
2. Maximum DC voltage on Output is V_CC +0.5V.
M27C400
Max
Unit
±1
µA
±10
µA
70
mA
50
mA
1
mA
100
µA
10
µA
0.8
V
V_CC + 1
V
0.4
V
V
System Considerations
The power switching characteristics of Advanced
CMOS EPROMs require careful decoupling of the
supplies to the devices. The supply current I_CC
has three segments of importance to the system
designer: the standby current, the active current
and the transient peaks that are produced by the
falling and rising edges of E. The magnitude of the
transient current peaks is dependent on the ca-
pacitive and inductive loading of the device out-
puts. The associated transient voltage peaks can
be suppressed by complying with the two line out-
put control and by properly selected decoupling
capacitors. It is recommended that a 0.1µF ceram-
ic capacitor is used on every device between V_CC
and V_SS. This should be a high frequency type of
low inherent inductance and should be placed as
close as possible to the device. In addition, a
4.7µF electrolytic capacitor should be used be-
tween V_CC and V_SS for every eight devices. This
capacitor should be mounted near the power sup-
ply connection point. The purpose of this capacitor
is to overcome the voltage drop caused by the in-
ductive effects of PCB traces.
Programming
When delivered (and after each erasure for UV
EPROM), all bits of the M27C400 are in the '1'
state. Data is introduced by selectively program-
ming '0's into the desired bit locations. Although
only '0's will be programmed, both '1's and '0's can
be present in the data word. The only way to
change a '0' to a '1' is by die exposition to ultravio-
let light (UVEPROM). The M27C400 is in the pro-
gramming mode when V_PP input is at 12.5V, G is
at V_IH and E is pulsed to V_IL. The data to be pro-
grammed is applied to 16 bits in parallel to the data
output pins. The levels required for the address
and data inputs are TTL. V_CC is specified to be
6.25V ± 0.25V.
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