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UC3846N Current Mode PWM Controller IC 40V 500mA DIP-16

UC3846N – Current Mode PWM Controller, 40V, 500mA Peak Output, 500kHz, 5.1V ±1% Ref, UVLO, Soft-Start, Shutdown, 16-Pin PDIP (DIP-16). 0°C to +70°C.

35.00 EGP

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SKU:3496300160716
UC3846N Current Mode PWM Controller IC 40V 500mA DIP-16

The UC3846N is a member of UCx846/7 family of current-mode PWM control devices, packaged in a 16-pin PDIP (through-hole) package. It provides all of the necessary features to implement off-line or DC-to-DC fixed-frequency, current-mode control schemes while maintaining a minimum external parts count.

Internally implemented circuits include an undervoltage lockout featuring start-up current less than 1 mA, a precision reference trimmed for accuracy at the error amplifier input, logic to ensure latched operation, a PWM comparator which also provides current-limit control, and a totem-pole output stage designed to source or sink high peak current. The output stage is suitable for driving either N-channel MOSFETs or bipolar transistor switches and is low in the OFF state.

Features
  • Automatic feedforward compensation
  • Programmable pulse-by-pulse current limiting
  • Automatic symmetry correction in push-pull configuration
  • Enhanced load response characteristics
  • Parallel operation capability for modular power systems
  • Differential current sense amplifier with wide common-mode range
  • Double-pulse suppression
  • 500-mA (peak) totem-pole outputs
  • ±1% bandgap reference
  • Undervoltage lockout
  • Soft-start capability
  • Shutdown terminal (complete shutdown with auto-restart or latched shutdown)
  • 500-kHz operation
  • Outputs LOW in the OFF state (suitable for driving N-channel MOSFETs or bipolar transistor switches)
  • Start-up current less than 1 mA
Specifications
Specification Value
Product Information
Part Number UC3846N
Manufacturer Texas Instruments (TI)
Product Family UCx846/7 Current Mode PWM Controller
Package PDIP (N) – 16 Pins, Through Hole
Body Size (Nominal) 6.35 mm × 19.3 mm
Operating Temperature Range 0°C to +70°C
RoHS Compliant Yes (Lead Finish: NIPDAU)
Shipping Packaging Tube, 25 pcs
Product Status NRND (Not Recommended for New Designs)
Absolute Maximum Ratings
Supply Voltage (VIN, Pin 15) 40 V
Collector Supply Voltage (VC, Pin 13) 40 V
Output Current, Source or Sink (Pins 11, 14) 500 mA
Analog Inputs (Pins 3, 4, 5, 6, 16) –0.3 V to +VIN
Reference Output Current (Pin 2) –30 mA
Sync Output Current (Pin 10) –5 mA
Error Amplifier Output Current (Pin 7) –5 mA
Soft Start Sink Current (Pin 1) 50 mA
Oscillator Charging Current (Pin 9) 5 mA
Power Dissipation @ TA = 25°C 1000 mW
Power Dissipation @ TC = 25°C 2000 mW
Storage Temperature –65°C to +150°C
Reference (VREF)
Output Voltage (TJ = 25°C, IO = 1 mA) 5.10 V typ (5.00 V to 5.20 V)
Line Regulation (VIN = 8 V to 40 V) 5 mV typ / 20 mV max
Load Regulation (IL = 1 mA to 10 mA) 3 mV typ / 15 mV max
Total Output Variation (Line, Load, Temp.) 4.95 V to 5.25 V
Short Circuit Output Current –10 mA to –45 mA
Oscillator
Initial Accuracy (TJ = 25°C) 43 kHz typ (39 kHz to 47 kHz)
Voltage Stability (VIN = 8 V to 40 V) –1% to 2%
Temperature Stability –1%
Maximum Operation 500-kHz operation (waveform clarity in excess of 1 MHz)
Error Amplifier
Input Offset Voltage 0.5 mV typ / 10 mV max
Input Bias Current –0.6 µA typ / –2 µA max
Common Mode Range 0 V to (VIN – 2 V)
Open Loop Voltage Gain 105 dB typ / 80 dB min
Unity Gain Bandwidth 1.0 MHz typ / 0.7 MHz min
CMRR (VCM = 0 V to 38 V) 100 dB typ / 75 dB min
PSRR (VIN = 8 V to 40 V) 105 dB typ / 80 dB min
Current Sense Amplifier
Amplifier Gain 2.75 V typ (2.5 V to 3.0 V)
Maximum Differential Input Signal 1.2 V max
Input Common Mode Range 0 V to (VIN – 3 V)
Input Offset Voltage 5 mV typ / 25 mV max
Delay to Outputs 200 ns typ / 500 ns max
Current Limit Adjust & Shutdown
Current Limit Offset 0.5 V typ (0.45 V to 0.55 V)
Shutdown Threshold Voltage 350 mV typ (250 mV to 400 mV)
Shutdown Input Voltage Range 0 V to VIN
Shutdown Delay to Outputs 300 ns typ / 600 ns max
Output Stage
Collector-Emitter Voltage 40 V
Output Low Level (ISINK = 100 mA) 0.4 V typ / 2.1 V max
Output High Level (ISOURCE = 100 mA) 12 V min / 13.5 V max
Rise Time (CL = 1 nF) 50 ns typ / 300 ns max
Fall Time (CL = 1 nF) 50 ns typ / 300 ns max
Undervoltage Lockout (UVLO) & Supply
Start-Up Threshold 8.0 V typ (7.7 V min)
Threshold Hysteresis 0.75 V
Total Standby Supply Current 17 mA typ / 21 mA max
ESD & Thermal Ratings
ESD – Human Body Model (HBM) ±2500 V
ESD – Charged Device Model (CDM) ±1500 V
RθJA (Junction-to-Ambient) 41.8 °C/W
RθJC(top) (Junction-to-Case) 28.5 °C/W
RθJB (Junction-to-Board) 21.8 °C/W

Applications
  • Telecommunication power converters
  • Industrial power converters
  • Off-line and DC-to-DC fixed-frequency, current-mode power supplies
  • Parallel / modular power systems with equal current sharing
Package Content
  • 1 x UC3846N Current Mode PWM Controller IC 40V 500mA DIP-16
DataSheet
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