AT89C4051 Atmel Corporation, AT89C4051 Datasheet - Page 4

• Manufacturer Part Number: AT89C4051
• Manufacturer: Atmel Corporation

Specifications of AT89C4051

• Flash (kbytes): 4 Kbytes
• Max. Operating Frequency: 24 MHz
• Cpu: 8051-12C
• Max I/o Pins: 15
• Uart: 1
• Sram (kbytes): 0.125
• Operating Voltage (vcc): 2.7 to 6.0
• Timers: 2

4.7
5. Oscillator Characteristics
4
XTAL2
AT89C4051
Output from the inverting oscillator amplifier.
XTAL1 and XTAL2 are the input and output, respectively, of an inverting amplifier which can be
configured for use as an on-chip oscillator, as shown in
ceramic resonator may be used. To drive the device from an external clock source, XTAL2
should be left unconnected while XTAL1 is driven as shown in
ments on the duty cycle of the external clock signal, since the input to the internal clocking
circuitry is through a divide-by-two flip-flop, but minimum and maximum voltage high and low
time specifications must be observed.
Figure 5-1.
Note:
Figure 5-2.
C1, C2 = 30 pF ± 10 pF for Crystals
Oscillator Connections
External Clock Drive Configuration
= 40 pF ± 10 pF for Ceramic Resonators
Figure
Figure
5-1. Either a quartz crystal or
5-2. There are no require-
1001F–MICRO–6/08