beautypg.com

Rainbow Electronics AT89C5132 User Manual

Page 153

background image

153

AT8xC5132

4173A–8051–08/02

Waveforms

Figure 131. Flash Memory – ISP Waveforms

Note:

ISP must be driven through a pull-down resistor (see Section “In-system Programming”,
page 140
).

Figure 132. Flash Memory – Internal Busy Waveforms

External Clock Drive and Logic Level References

Definition of Symbols

Table 145. External Clock Timing Symbol Definitions

Timings

Table 146. External Clock AC Timings

V

DD

= 2.7 to 3.3V, T

A

= 0 to 70

°

C

Waveforms

Figure 133. External Clock Waveform

RST

T

SVRL

ISP1

T

RLSX

FBUSY bit

T

BHBL

Signals

Conditions

C

Clock

H

High

L

Low

X

No Longer Valid

Symbol

Parameter

Min

Max

Unit

T

CLCL

Clock Period

50

ns

T

CHCX

High Time

10

ns

T

CLCX

Low Time

10

ns

T

CLCH

Rise Time

3

ns

T

CHCL

Fall Time

3

ns

T

CR

Cyclic Ratio in X2 Mode

40

60

%

0.45 V

T

CLCL

V

DD

- 0.5

V

IH1

V

IL

T

CHCX

T

CLCH

T

CHCL

T

CLCX