Device
Operating
Temperature Range
Package
SEMICONDUCTOR
TECHNICAL DATA
ALTERNATOR VOLTAGE
REGULATOR
ORDERING INFORMATION
MC33092ADW
T
A
= – 35
°
to +125
°
C
SO–20L
PIN CONNECTIONS
DW SUFFIX
PLASTIC PACKAGE
CASE 751D
(SO–20L)
20
1
1
20
19
18
17
16
15
14
13
12
11
2
3
4
5
6
7
8
9
(Top View)
Filter Buffer
Remote Sense
Lamp Collector
Lamp Base
Oscillator
Adjust
V
ref
Undervoltage
Source
Gate
NC
Gnd
V
CC
1
V
CC
3
Supply
Regulation
V
ref
Oscillator
10
Phase
Rate
Gnd
1
MOTOROLA ANALOG IC DEVICE DATA
The MC33092A is specifically designed for voltage regulation and Load
Response Control (LRC) of diode rectified alternator charging systems, as
commonly found in automotive applications. The MC33092A provides load
response control of the alternator output current to eliminate engine speed
hunting and vibration due to sudden electrical loads which cause abrupt
torque loading of the engine at low RPM. Two load response rates are
selectable using Pin 11. The timing of the response rates is dependent on
the oscillator frequency.
In maintaining system voltage, the MC33092A monitors and compares
the system battery voltage to an externally programmed set point value and
pulse width modulates an N–channel MOSFET transistor to control the
average alternator field current.
Forced Load Response Control (LRC) with Heavy Load Transitions
at Low RPM
Capable of Regulating Voltage to
±
0.1 V @ 25
°
C
Operating Frequency Selectable with One External Resistor
< 0.1 V Variation over Speed Range of 2000 to 10,000 RPM
< 0.4 V Variation over 10% to 95% of Maximum Alternator Output
Maintains Regulation with External Loads as Low as 1.0 A
Load Dump Protection of Lamp, Field Control Devices, and Loads
Duty Cycle Limit Protection
Provides High Side MOSFET Control of a Ground Referenced Field
Winding
Controlled MOSFET and Flyback Diode Recovery Characteristics for
Minimum RFI
< 2.0 mA Standby Current from Battery @ 25
°
C
< 3.0 mA Standby Current from Battery Over Temperature Range
Optional 2.5 or 10 sec. LRC Rate Control (Osc. Freq. = 280 kHz)
Undervoltage, Overvoltage and Phase Fault (Broken Belt) Detection
Simplified Block Diagram
Oscillator
Osc.
Adjust
FB
UV
V
ref
V
ref
8
V
CC
1
14
V
CC
3
13
17
Gate
18
Source
3
Lamp
Coll.
4
Lamp
Base
5
Gnd
Bias
Undervoltage
Load Dump
Overvoltage
Regulate
8
12
Rate
MC33092A
7
Phase
10
Supply
Reg
(Local)
12
Sense
(Remote)
2
Lamp
Control
Logic
Charge
Pump
Power
Supply
Up/Down
Counter
(2
4
)
Divide By
(1/12/48)
Control
Logic
Output
Control
Bandgap
Reference
DAC
Counter
(2
)
Oscillator
Prescaler
(2
)
Counter
Low
Pass
Filter
Signal
Combiner
and Switch
Lost
Sense
Circuit
4
Power
Up/Down
Circuit
X1
Buff
1
19
20
15
6
Gnd
9
11
Motorola, Inc. 1997
Rev 0
F
Freescale Semiconductor, Inc.
Go to: www.freescale.com
n
.