8XC525458

Table 5 Program Lock Bits and the Features

Program Lock Bits

Protection Type

LB1

LB2

LB3

1

U

U

U

No Program Lock features enabled (Code verify will still be encrypted by the

Encryption Array if programmed)

2

P

U

U

MOVC instructions executed from external program memory are disabled from

fetching code bytes from internal memory EA is sampled and latched on

Reset and further programming of the EPROM is disabled

3

P

P

U

Same as 2 also verify is disabled

4

P

P

P

Same as 3 also external execution is disabled

NOTE

Any other combination of the lock bits is not defined

EPROM PROGRAMMING AND VERIFICATION CHARACTERISTICS

Symbol

Parameter

Min

Max

Units

Programming Supply Voltage

125

130

V

Programming Supply Current

75

mA

1TCLCL

Oscillator Frequency

4

6

MHz

TAVGL

Address Setup to PROG Low

48TCLCL

TGHAX

Address Hold after PROG

48TCLCL

TDVGL

Data Setup to PROG Low

48TCLCL

TGHDX

Data Hold after PROG

48TCLCL

TEHSH

48TCLCL

TSHGL

10

m

s

TGHSL

10

m

s

TGLGH

PROG Width

90

110

m

s

TAVQV

Address to Data Valid

48TCLCL

TELQV

ENABLE Low to Data Valid

48TCLCL

TEHQZ

Data Float after ENABLE

0

48TCLCL

TGHGL

PROG High to PROG Low

10

m

s

22