DS87C530_05 Datasheet, PDF (4/47 Pages) Dallas Semiconductor – EPROM/ROM Microcontrollers with Real-Time Clock

Figure 1. Block Diagram
DS87C530/DS83C530 EPROM/ROM Microcontrollers with Real-Time Clock
DS87C530/
DS83C530
PIN DESCRIPTION
PIN
PLCC TQFP
52
45
1, 25
18, 46
29
22
26
19
NAME
V_CC
GND
V_CC2
GND2
12
5
RST
23
16
XTAL2
24
17
XTAL1
FUNCTION
+5V Processor Power Supply
Processor Digital Circuit Ground
+5V RTC Supply. V_CC2 is isolated from V_CC to isolate the RTC from digital noise.
RTC Circuit Ground
Reset Input. This pin contains a Schmitt voltage input to recognize external active
high reset inputs. The pin also employs an internal pulldown resistor to allow for a
combination of wired OR external reset sources. An RC is not required for power-up,
as the device provides this function internally.
Crystal Oscillator Pins. XTAL1 and XTAL2 provide support for parallel-resonant,
AT-cut crystals. XTAL1 acts also as an input if there is an external clock source in
place of a crystal. XTAL2 is the output of the crystal amplifier.
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