SL494 SLS

Document overview

  • Manufacturer or author: Provided By www.digicamel.com(FREE DATASHEET DOWNLOAD SITE)
  • PDF pages: 4

Technical content

The SL494 incorporates on a single monolithic chip all the functions required in the construction of a pulse -width-modulation control circuit. Designed primarily for power supply control, the SL494 contains an on -chip 5 -volt regulator, two error amplifiers, adjustable oscillator, dead -time control comparator, pulse -steering flip -flop, and output -control circuitry. The uncommitted ou tput transistors provide either common-emitter or emitter-follower output capability. Push -pull or single-ended output operation may be selected through the output - control function. The architecture of the IL494 prohibits the possibility of either output b eing pulsed twice during push -pull operation.

  • Complete PWM Power Control Circuitry
  • Uncommitted Outputs for 200 mA Sink or Source
  • Output Control Selects Single -Ended or Push -Pull Operation
  • Internal Circuitry Prohibits Double Pulse at Either Output
  • Internal Regulator Provides a Stable 5 V Reference Supply
  • Variable Dead-Time Provides Control Over Total Range

ORDERING INFORMATION

TA = -20°C to 85° C for all packages PIN ASSIGNMENT FUNCTION TABLE Output Control Output Function Grounded Single-ended or Parallel Output At Vref Normal Push-Pull Operation LOGIC DIAGRAM

Symbol Parameter Value Unit VCC Supply Voltage 41 V VI Amplifier Input Voltage VCC +0.3 V VO Collector Output Voltage 41 V Collector Output Current 250 mA Tstg Storage Temperature -65 to +150 °C RECOMMENDED OPERATING CONDITIONS Symbol Parameter Min Max Unit VCC Supply Voltage 7 40 V VI Amplifier Input Voltage -0.3 VCC - 2 V VO Collector Output Voltage 40 V Collector Output Current (Each Transistor) 200 mA Current Into Feed back Terminal 0.3 mA CT Timing Capacitor 0.47 10.000 nF RT Timing Resistor 1.8 500 KΩ Oscillator Frequency 1 300 KHz TA Operating Free-Air Temperature -20 +85 °C

ELECTRICAL CHARACTERISTICS (Temperature -20 ∼ 85°C, VCC = 15 V, f=10 kHz)) Symbol Parameter Test Conditions Min Max Unit Reference Section Vref Output Voltage IO=1 mA 4.75 5.25 V Vregin Output regulation VCC=7 V to 40 V, TA=25°C 25 mV Vregout Input regulation IO=1 to 10 mA, TA=25°C 15 mV ΔVref Output Voltage change with temperature TA= -20°C to 85°C 1 % ISC Short-circuit output current (Note 1) Vref=0 50 mA Oscillator Section fOSC Frequency CT=0.01 µF, RT=12 kΩ 6 14 KHz δfOSC Standard deviation of frequency (Note 2) All values of VCC, CT, RT, TA Constant 15 % δfOSC(ΔV) Frequency change with voltage VCC= 7 V to 40 V, TA=25°C 10 % δfOSC(ΔT) Frequency change with temperature CT=0.01 µF, RT=12 kΩ TA= -20°C to 85°C 2 % Dead Time Control Section IIB(2T) Input bias current (pin 4) VI= 0 to 5.25 V -10 µA DCmax Maximum duty cycle, each output VI(pin 4)=0 V 45 % VTHD Input threshold voltage Zero duty cycle 3.3 V (pin 4) Maximum duty cycle 0 Error Amp Section VIO Input offset voltage VO(pin 3)=2.5 V 10 mV IIO Input offset current VO(pin 3)=2.5 V 250 nA IIB Input bias cur rent VO(pin 3)=2.5 V 1 µA Common-mode input VCC= 7 V to 40 V LOW -0.3 V voltage range HIGH VCC - 2 Avol Open-loop voltage amplification ΔVO=3 V, VO=0.5 to 3.5 V 70 dB fb Unity-gain bandwidth 100 kHz CMRR Common-mode rejection ratio VCC=40 V, TA=25°C 65 dB IO Output sink current (pin 3) VID=-15 mV to -5 V, VO(pin 3)=0.7 V 0.3 mA IO+ Output source current (pin 3) VID=15 mV to 5 V, VO(pin 3)=3.5 V -2 mA

ELECTRICAL CHARACTERISTICS(Temperature -20 ∼ 85°C, VCC = 15 V, f=10 kHz)) Symbol Parameter Test Conditions Min Max Unit PWM Comparator Section VTHP Input threshold voltage (pin 3) Zero duty cycle 4.5 V II Input sink current (pin 3) VO(pin 3)=0.7 V 0.3 mA Switching Characteristics trc Output voltage rise time Common-emitter configuration 200 ns tfc Output voltage fall time Common-emitter configuration 100 ns trf Output voltage rise time Emitter-follower configuration 200 ns tff Output voltage fall time Emitter-follower configuration 100 ns Output Section IC(off) Collector off-state current VCE=40 V, VCC=40 V 100 µA IE(off) Emitter off-state current VCC=VC=40 V, VE=0 -100 µA VSAT Collector- emitter Common- emitter VE=0, IC=200 mA 1.3 V saturation voltage Emitter- follower VC=15 V, IE=-200 mA 2.5 IOCH Output control input current VI=Vref 3.5 mA Total Device ICC Standby supply current All other inputs & VCC=15 V 10 mA outputs open VCC=40 V 15 ICCA Average supply current V(pin 4)=2 V 17 mA Notes: 1. Duration of the short circuit should not exceed one second. 2. Standard deviation is a measure of the statistical disribution about the mean as derived from the formula N ∑ (xn - x)2 n=1 σ = N - 1