AC Parameters
AC Test Conditions
Input Pulse Levels:....................................GND to 3.0V
Input Rise/Fall Times: ...............................5 ns
Input Timing Reference Levels: ................1.5V
Output loading IOL/IOH (see Figure 1 and Figure 2)+30 pF
AC Test Loads Waveforms
Figure 1
Figure 2
Figure 3
Data Retention Mode
Atmel CMOS RAM’s are designed with battery backup in mind. Data retention voltage and sup-
ply current are guaranteed over temperature. The following rules ensure data retention:
1. During data retention chip select CS1 must be held high within VCC to VCC -0.2V or,
chip select CS2 must be held down within GND to GND +0.2V.
2. Output Enable (OE) should be held high to keep the RAM outputs high impedance, mini-
mizing power dissipation.
3. During power up and power-down transitions CS1 and OE must be kept between VCC +
0.3V and 70% of VCC, or with CS2 between GND and GND -0.3V.
4. The RAM can begin operation > TR ns after VCC reaches the minimum operation volt-
ages (4.5V).
Timing
6
M65608E
4151N–AERO–04/09
ATMEL [ ATMEL ]
