M48T513V-85CS1 STMicroelectronics, M48T513V-85CS1 Datasheet - Page 21

• Manufacturer Part Number: M48T513V-85CS1
• Manufacturer: STMicroelectronics
• Type: NVSRAMr

Specifications of M48T513V-85CS1

• Word Size: 8b
• Organization: 512x8
• Density: 4Mb
• Interface Type: Parallel
• Access Time (max): 85ns
• Operating Supply Voltage (typ): 3.3V
• Operating Temperature Classification: Commercial
• Operating Supply Voltage (max): 3.6V
• Operating Supply Voltage (min): 3V
• Operating Temp Range: 0C to 70C
• Pin Count: 32
• Mounting: Surface Mount
• Supply Current: 60mA
• Lead Free Status / RoHS Status: Supplier Unconfirmed

Power-on Reset
The M48T513Y/V continuously monitors V
When V
the RST pulls low (open drain) and remains low on
power-up for t
RST pin is an open drain output and an appropri-
ate pull-up resistor to V
control the rise time.
Reset Input (RSTIN)
The M48T513Y/V provides an independent input
which can generate an output reset. The duration
and function of this reset is identical to a reset gen-
erated by a power cycle. Table 13 and Figure 15
illustrate the AC reset characteristics of this func-
tion. Pulses shorter than t
set condition. RSTIN is internally pulled up to V
through a 100K resistor.
Battery Low Warning
The M48T513Y/V automatically performs battery
voltage monitoring upon power-up and at factory-
programmed time intervals of approximately 24
hours. The Battery Low (BL) Bit, Bit D4 of Flags
Register 7FFF0h, will be asserted if the battery
voltage is found to be less than approximately
2.5V.
Figure 15. RSTIN Timing Waveform
Table 13. Reset AC Characteristics
Note: 1. Valid for Ambient Operating Temperature: T
2. C
Symbol
t
RHRZ
CC
t
L
R
= 5pF (see Figure Figure 7, page 8)
RSTIN
RST
(2)
falls to the power fail detect trip point,
REC
RSTIN Low to RST Low
RSTIN High to RST Hi-Z
after V
CC
R
CC
will not generate a re-
should be chosen to
passes V
Parameter
Hi-Z
A
PFD
= 0 to 70 C; V
(1)
. The
CC
CC
.
CC
If a battery low is generated during a power-up se-
quence, this indicates that the battery is below ap-
proximately 2.5 volts and may not be able to
maintain data integrity in the SRAM. Data should
be considered suspect and verified as correct.
If a battery low indication is generated during the
24-hour interval check, this indicates that the bat-
tery is near end of life. However, data is not com-
promised due to the fact that a nominal V
supplied.
The M48T513Y/V only monitors the battery when
a nominal V
cations which require extensive durations in the
battery back-up mode should be powered-up peri-
odically (at least once every few months) in order
for this technique to be beneficial. Additionally, if a
battery low is indicated, data integrity should be
verified upon power-up via a checksum or other
technique.
Initial Power-on Defaults
Upon application of power to the device, the fol-
lowing register bits are set to a ’0’ state: WDS,
BMB0-BMB4, RB0,RB1, AFE, ABE, W, R and FT.
= 4.5 to 5.5V or 3.0 to 3.6V (except where noted).
tR
CC
Min
20
40
is applied to the device. Thus appli-
M48T513Y, M48T513V
tRHRZ
Max
100
200
AI02585
Hi-Z
Unit
ms
ms
CC
21/31
is