MC34023 Datasheet, PDF (1/19 Pages) ON Semiconductor – High Speed Single-Ended PWM Controller

High Speed Single-Ended
PWM Controller
The MC34023 series are high speed, fixed frequency, single–ended pulse
width modulator controllers optimized for high frequency operation. They are
specifically designed for Off–Line and DC–to–DC converter applications
offering the designer a cost–effective solution with minimal external
components. These integrated circuits feature an oscillator, a temperature
compensated reference, a wide bandwidth error amplifier, a high speed
current sensing comparator, and a high current totem pole output ideally
suited for driving a power MOSFET.
Also included are protective features consisting of input and reference
undervoltage lockouts each with hysteresis, cycle–by–cycle current limiting,
and a latch for single pulse metering.
The flexibility of this series allows it to be easily configured for either
current mode or voltage mode control.
• 50 ns Propagation Delay to Output
• High Current Totem Pole Output
• Wide Bandwidth Error Amplifier
• Fully–Latched Logic with Double Pulse Suppression
• Latching PWM for Cycle–By–Cycle Current Limiting
• Soft–Start Control with Latched Overcurrent Reset
• Input Undervoltage Lockout with Hysteresis
• Low Start–Up Current (500 µA Typ)
• Internally Trimmed Reference with Undervoltage Lockout
• 90% Maximum Duty Cycle (Externally Adjustable)
• Precision Trimmed Oscillator
• Voltage or Current Mode Operation to 1.0 MHz
• Functionally Similar to the UC3823
Order this document by MC34023/D
MC34023
MC33023
16
1
P SUFFIX
PLASTIC PACKAGE
CASE 648
16
1
DW SUFFIX
PLASTIC PACKAGE
CASE 751G
(SO–16L)
PIN CONNECTIONS
16
Vref
4
Clock
5
RT
6
CT
7
Ramp
Error Amp 3
Output
Noninverting
Input
2
Inverting
Input
1
8
Soft–Start
Simplified Application
Oscillator
5.1V
Reference
UVLO
Latching
Error
PWM
Amp
Soft–Start
10 Ground
This device contains 176 active transistors.
MOTOROLA ANALOG IC DEVICE DATA
15
VCC
13
VC
14
Output
12
Power
Ground
11
Current
9
Limit Ref
Current
Limit/
Shutdown
Error Amp
Inverting Input ¹
Error Amp
Noninverting Input
2
Error Amp Output 3
16 Vref
15 VCC
14 Output
Clock ⁴
13 VC
RT 5
CT 6
Ramp 7
Soft–Start ⁸
12 Power Ground
11 ^{Current Limit}
Reference
10 Ground
9 ^{Current Limit/}
Shutdown
(Top View)
ORDERING INFORMATION
Device
MC33023P
MC33023DW
MC34023P
Operating
Temperature Range Package
Plastic DIP
TA = – 40° to +105°C
SO–16L
TA = 0° to +70°C Plastic DIP
© Motorola, Inc. 1996
Rev 2
1