Philips Semiconductors
Threshold detector and reset generator
Product specification
PCF1252-X family
103
handbook, full pagewidth
tR(1)
(ms)
102
MGC922 102
tS(2)
(ms)
10
10
1
1
10−1
10−1
10−3
10−2
(1) tR (typ.) = (0.1 + CCT) ms.
(2) tS (typ.) = (0.01 + 0.1 CCT) ms.
10−1
10−2
1
10
102
103
external capacitor (nF)
Fig.8 Reset and save times as a function of the external capacitor (CCT).
APPLICATION INFORMATION
handbook, full pagewidth
VDD
(+5 V)
VSS
(0 V)
PCF1252-X VDD
COMIN
RESET
SELECT
VSS
CT
1 nF
VDD
RESET
MICROCONTROLLER/
MICROPROCESSOR
VSS
MGC923
Fig.9 Typical power-on reset circuit for a microcontroller/microprocessor system; (when not used, COMIN must
be connected to VDD).
1998 Apr 16
8