CA3277
April 1994
Dual 5V Regulator with Serial Data Buffer
Interface for Microcontroller Applications
Description
The CA3277 is a Dual 5V Voltage Regulator IC intended for micro-
processor and logic controller applications. It is supplied with fea-
tures that are commonly speci鏗乪d for sequentially controlled
shutdown and startup requirements of microcontrollers. Over-volt-
age shutdown, short circuit current limiting and thermal shutdown
features are provided for protection in the harsh environmental appli-
cations of industrial and automotive systems. The CA3277 functions
are complementary to the needs of microcontroller and memory cir-
cuits, providing for sustained memory with a 5V standby output.
The Ignition Comparator senses the voltage level at the IGN IN input
and provides a 5V logic switched output (supply sourced from
OUT1). The Ignition Output, IGN OUT can be used to signal a sys-
tem microcontroller which can respond with a logic switched output
to the CA3277 ENABLE input control for OUT2. The OUT1 +5V
Standby Supply of the regulator is normally used as a power supply
for microcontroller/memory circuits to preserve stored data when in
the standby mode.To allow for maximum heat transfer from the chip,
the four center leads are directly connected to the die mounting pad.
Refer to AN9302 for further information on CA3277 circuit Applica-
tions.
Features
鈥?Dual 5V Regulator
- V
OUT
1 at 5V 100mA - Standby
- V
OUT
2 at 5V 100mA - Enabled
- Regulation Range 6V to 18V
- Bandgap Voltage References
鈥?Low Quiescent Idle Current, 500碌A Typ.
鈥?Over-Voltage Shutdown Protection, 20.5V Typ.
鈥?Reverse Battery Protection, -26V Max.
鈥?Thermal Shutdown Protection
鈥?Short Circuit Current Limiting
鈥?Low Input P.S. Flag and Delayed Reset Control
鈥?Low Voltage Shutdown Control, Ouput1
鈥?Ignition Comparator Logic Level Control
鈥?Data Comparator and 100X Current Mult. Used
as Input/Output Buffers for Remote Serial Data
Communication
Applications
鈥?Automotive 5V Regulators and Data Buffers
鈥?Industrial Controller Remote System
鈥?Microcontroller and Memory Power Supply
鈥?Radio, TV, CATV, Consumer Applications
Ordering Information
PART NUMBER
CA3277E
TEMPERATURE RANGE
-40
o
C to +85
o
C
PACKAGE
16 Lead Plastic DIP
Pinout
CA3277 (PDIP)
TOP VIEW
BATT
OUT1
DATA IN
GND
GND
DATA OUT
CRST
RESET
1
2
3
4
5
6
7
8
16 IGN
15 OUT2
14 ENABLE
13 GND
12 GND
11 IGN OUT
10 CUR IN
9 CUR OUT
Functional Block Diagram
1
BATT
OVER-
VOLTAGE
SHTDWN
LOW
VOLTAGE
SHTDWN
+
BANDGAP
VOLTAGE
REF
1.2V
2
OUT1
+5V
(STANDBY)
-
OUT1 REG.
DR. CNTRL
+
-
RESET
8
7
CRST
15
OUT2
+5V
(ENABLE)
OVER-
TEMP
SHTDWN
ENABLE 14
(OUTPUT2)
+
-
-
OUT2 REG.
DR. CNTRL
+
DATA IN 3
IN
+
-
6
DATA
OUT
IGN IN
16
+
-
11
IGN
OUT
10
CUR
IN
CURRENT
MULTIPLIER
9
CUR
OUT
4, 5 AND
12, 13
GND
V
BATT
-2.9V
6V
CAUTION: These devices are sensitive to electrostatic discharge; follow proper IC Handling Procedures.
407-727-9207
|
Copyright
漏
Intersil Corporation 1999
File Number
2792.4
7-39
INTERSIL
1
2
3
4
5
6
7
8
