MAXDATA Belinea 101920, Руководство по обслуживанию

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Belinea Technical Service Manual
MC68HC705BD7B
RC1117X33
Features
•Low dropout voltage
•Load regulation: 0.05% typical
•Trimmed current limit
•On-chip thermal limiting
•Standard SOT-223, TO-263, and TO-252 packages
•Three-terminal adjustable or fixed 2.5V, 2.85V, 3.3V, 5V
Applications
•Active SCSI terminators
•High efficiency linear regulators
•Post regulators for switching supplies
•Battery chargers
•5V to 3.3V linear regulators
•Motherboard clock supplies
Description
The RC1117 and RC1117-2.5, -2.85, -3.3 and -5 are low
dropout three-terminal regulators with 1A output current
capability. These devices have been optimized for low voltage
where transient response and minimum input voltage are
critical. The 2.85V version is designed specifically to be
used in Active Terminators for SCSI bus.
Current limit is trimmed to ensure specified output current
and controlled short-circuit current. On-chip thermal limiting
provides protection against any combination of overload and
ambient temperatures that would create excessive junction
temperatures.
Unlike PNP type regulators where up to 10% of the output
current is wasted as quiescent current, the quiescent current
of the RC1117 flows into the load, increasing efficiency.
The RC1117 series regulators are available in the industry-
standard SOT-223, TO-263 (D2PAK), and TO-252 (DPAK)
power packages.
Typical Applications
V
IN
= 3.3V V
IN
V
OUT
ADJ
1.5V at 1A
RC1117
10 F 2 2 F
R1
124
R2
24.9
V
IN
= 5V V
IN
V
OUT
GND
2.85V at 1A
RC1117-2.85
10 F
+ +
+
+
22 F
V
OUT
= V
REF
(1 + R2/R1) + I
Adj
• R2