DS1990A-F3 Maxim Integrated Products, DS1990A-F3 Datasheet - Page 6

• Manufacturer Part Number: DS1990A-F3
• Description: Serial Number Registration
• Manufacturer: Maxim Integrated Products

Specifications of DS1990A-F3

• Lead Free Status / Rohs Status: No

Figure 5. ROM FUNCTIONS FLOW CHART
MATCH ROM [55h] / SKIP ROM [CCh]
The minimum set of 1-Wire ROM function commands includes a Match ROM and a Skip ROM command. Since the
DS1990A contains only the 64-bit ROM without any additional data fields, Match ROM and Skip ROM are not
applicable. The DS1990A will remain silent (inactive) upon receiving a ROM function command that it doesn't
support. This allows the DS1990A to coexist on a multidrop bus with other 1-Wire devices that do respond to Match
ROM or Skip ROM (example DS1990A and DS1994).
Bus Master TX ROM
Function Command
Serial Number
DS1990A TX
DS1990A TX
DS1990A TX
Command ?
Family Code
Read ROM
CRC Byte
(6 Bytes)
(1 Byte)
33h
Y
N
Presence Pulse
Bus Master TX
DS1990A TX
6 of 8
Reset Pulse
N
N
N
DS1990A
DS1990A
DS1990A TX Bit 0
DS1990A TX Bit 0
DS1990A TX Bit 1
DS1990A TX Bit 1
Master TX Bit 63
Master TX Bit 0
Master TX Bit 1
Search ROM
Command ?
Match ?
Match ?
Match ?
Bit 63
Bit 0
Bit 1
F0h
TX Bit 63
TX Bit 63
Y
Y
Y
Y
N