Sistemas De Control En Tiempo Discreto

Order this document by TL494/D

TL494 SWITCHMODE™ Pulse Width Modulation Control Circuit
The TL494 is a fixed frequency, pulse width modulation control circuit designed primarily for SWITCHMODE power supply control.

• • • • • • • •

SWITCHMODE PULSE WIDTH MODULATION CONTROL CIRCUIT
SEMICONDUCTOR TECHNICAL DATA

Complete Pulse Width Modulation Control Circuitry On–Chip Oscillator withMaster or Slave Operation On–Chip Error Amplifiers On–Chip 5.0 V Reference Adjustable Deadtime Control Uncommitted Output Transistors Rated to 500 mA Source or Sink Output Control for Push–Pull or Single–Ended Operation Undervoltage Lockout

D SUFFIX PLASTIC PACKAGE CASE 751B (SO–16)

N SUFFIX PLASTIC PACKAGE CASE 648

PIN CONNECTIONS
Noninv Input 1 Inv Input 2 Noninv 16 Input Inv 15 Input14 Vref Output 13 Control 12 VCC
Oscillator

MAXIMUM RATINGS (Full operating ambient temperature range applies,
unless otherwise noted.) Rating Power Supply Voltage Collector Output Voltage Collector Output Current (Each transistor) (Note 1) Amplifier Input Voltage Range Power Dissipation @ TA ≤ 45°C Thermal Resistance, Junction–to–Ambient Operating Junction Temperature Storage TemperatureRange Operating Ambient Temperature Range TL494C TL494I Derating Ambient Temperature
NOTE:

+ Error 1 Amp –

+ 2 Error Amp – VCC 5.0 V REF

Symbol VCC VC1, VC2 IC1, IC2 VIR PD RθJA TJ Tstg TA

TL494C 42 42 500

TL494I

Unit V V mA V mW °C/W °C °C °C

Compen/PWN Comp Input 3 Deadtime Control 4 CT 5 RT 6

≈ 0.1 V

11 C2
Q2

Ground 7

10 E2
Q1

–0.3 to +42 1000 80 125 –55 to+125 0 to +70 – 25 to +85

C1 8

9 E1

(Top View)

ORDERING INFORMATION
Device Operating Temperature Range TA = 0° to +70°C TA = – 25° to +85°C Package SO–16 Plastic Plastic
Rev 1

TA

45

°C

TL494CD TL494CN TL494IN

1. Maximum thermal limits must be observed.

© Motorola, Inc. 1996

MOTOROLA ANALOG IC DEVICE DATA

1

TL494
RECOMMENDED OPERATING CONDITIONSCharacteristics Power Supply Voltage Collector Output Voltage Collector Output Current (Each transistor) Amplified Input Voltage Current Into Feedback Terminal Reference Output Current Timing Resistor Timing Capacitor Oscillator Frequency Symbol VCC VC1, VC2 IC1, IC2 Vin lfb lref RT CT fosc Min 7.0 – – –0.3 – – 1.8 0.0047 1.0 Typ 15 30 – – – – 30 0.001 40 Max 40 40 200 VCC – 2.0 0.3 10 500 10 200 Unit V V mAV mA mA kΩ µF kHz

ELECTRICAL CHARACTERISTICS (VCC = 15 V, CT = 0.01 µF, RT = 12 kΩ, unless otherwise noted.) For typical values TA = 25°C, for min/max values TA is the operating ambient temperature range that applies, unless otherwise noted.
Characteristics REFERENCE SECTION Reference Voltage (IO = 1.0 mA) Line Regulation (VCC = 7.0 V to 40 V) Load Regulation (IO = 1.0 mA to 10 mA) ShortCircuit Output Current (Vref = 0 V) OUTPUT SECTION Collector Off–State Current (VCC = 40 V, VCE = 40 V) Emitter Off–State Current VCC = 40 V, VC = 40 V, VE = 0 V) Collector–Emitter Saturation Voltage (Note 2) Common–Emitter (VE = 0 V, IC = 200 mA) Emitter–Follower (VC = 15 V, IE = –200 mA) Output Control Pin Current Low State (VOC ≤ 0.4 V) High State (VOC = Vref) Output Voltage Rise TimeCommon–Emitter (See Figure 12) Emitter–Follower (See Figure 13) Output Voltage Fall Time Common–Emitter (See Figure 12) Emitter–Follower (See Figure 13) IC(off) IE(off) – – 2.0 – 100 –100 µA µA V Vsat(C) Vsat(E) IOCL IOCH tr – – tf – – 25 40 100 100 100 100 200 200 ns – – – – 1.1 1.5 10 0.2 1.3 2.5 – 3.5 µA mA ns Vref Regline Regload ISC 4.75 – – 15 5.0 2.0 3.0 35 5.25 25 15 75 V mV mV mA Symbol Min Typ Max UnitNOTE: 2. Low duty cycle pulse techniques are used during test to maintain junction temperature as close to ambient temperature as possible.

2

MOTOROLA ANALOG IC DEVICE DATA

TL494
ELECTRICAL CHARACTERISTICS (VCC = 15 V, CT = 0.01 µF, RT = 12 kΩ, unless otherwise noted.) For typical values TA = 25°C, for min/max values TA is the operating ambient temperature range that applies,...