87LPC764 Datasheet, PDF (47/56 Pages) NXP Semiconductors – Low power, low price, low pin count 20 pin microcontroller with 4 kbyte OTP

Philips Semiconductors
Low power, low price, low pin count (20 pin)
microcontroller with 4 kbyte OTP
Preliminary data
87LPC764
UCFG2 Address: FD01h
Unprogrammed Value: FFh
7
6
5
4
3
2
1
0
SB2
SB1
—
—
—
—
—
—
BIT
UCFG2.7, 6
UCFG2.5–0
SYMBOL
SB2, SB1
—
FUNCTION
EPROM security bits. See table entitled, “EPROM Security Bits” for details.
Reserved for future use.
Figure 37. EPROM System Configuration Byte 2 (UCFG2)
SU01186
Security Bits
When neither of the security bits are programmed, the code in the EPROM can be verified. When only security bit 1 is programmed, all further
programming of the EPROM is disabled. At that point, only security bit 2 may still be programmed. When both security bits are programmed,
EPROM verify is also disabled.
Table 11. EPROM Security Bits
SB2
SB1
Protection Description
1
1
Both security bits unprogrammed. No program security features enabled. EPROM is programmable and verifiable.
1
0
Only security bit 1 programmed. Further EPROM programming is disabled. Security bit 2 may still be programmed.
0
1
Only security bit 2 programmed. This combination is not supported.
0
0
Both security bits programmed. All EPROM verification and programming are disabled.
ABSOLUTE MAXIMUM RATINGS
PARAMETER
RATING
UNIT
Operating temperature under bias
–55 to +125
°C
Storage temperature range
–65 to +150
°C
Voltage on RST/V_PP pin to V_SS
0 to +11.0
V
Voltage on any other pin to V_SS
–0.5 to V_DD+0.5V
V
Maximum I_OL per I/O pin
20
mA
Power dissipation (based on package heat transfer, not device power consumption)
1.5
W
NOTES:
1. Stresses above those listed under Absolute Maximum Ratings may cause permanent damage to the device. This is a stress rating only and
functional operation of the device at these or any conditions other than those described in the AC and DC Electrical Characteristics section
of this specification are not implied.
2. This product includes circuitry specifically designed for the protection of its internal devices from the damaging effects of excessive static
charge. Nonetheless, it is suggested that conventional precautions be taken to avoid applying greater than the rated maximum.
3. Parameters are valid over operating temperature range unless otherwise specified. All voltages are with respect to VSS unless otherwise noted.
2001 Oct 26
44