AC/DC and DC/DC Power Supplies - PWM Power Supply Controllers - UC3843A

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Datasheet

Current Mode PWM Controller (Rev. B) (PDF 3638 KB)
04 Sep 2009

Functional Block Diagram

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	UC1843A	UC2843A	UC3843A
Topology	Boost, Flyback, Forward	Boost, Flyback, Forward	Boost, Buck, Flyback, Forward
Control Method	Current Mode	Current Mode	Current Mode
Duty Cycle(Max)(%)	100	100	100
PWM Outputs(#)	1	1	1
Frequency(Max)(kHz)	450	450	450
UVLO Thresholds On/Off(V)	8.4/7.6	8.4/7.6	8.4/7.6
Pin/Package	20LCCC, 8CDIP	14SOIC, 20PLCC, 8PDIP, 8SOIC	14SOIC, 8PDIP, 8SOIC
Regulated Outputs(#)	1	1	1
	Samples	Samples	Samples
	Inventory	Inventory	Inventory

Other qualified versions of UC3843A

Version	Part Number	Definition
Enhanced Product	UC1843A-EP	Supports Defense, Aerospace and Medical Applications
Military	UC1843A	QML certified for Military and Defense Applications
Space	UC1843A-SP	Radiation tolerant, ceramic packaging and qualified for use in Space-based application

Customers Who Evaluated This Product Also Evaluated

TL494: PWM Control Circuit
UC3845A: Current Mode PWM Controller
UCC28600: 8-Pin Quasi Resonant Flyback Green Mode Controller
TPS54231: 2A, 28V Input, 570 kHz Step Down SWIFT™ DC/DC Converter with Eco-Mode ™
TPS54620: 4.5V to 17V Input, 6A Synchronous Step Down SWIFT™ Converter
TL431A: Adjustable Precision Shunt Regulator

More Related Products

Product Information

Features

Optimized for Off-line and DC to DC Converters
Low Start Up Current (<0.5mA)
Trimmed Oscillator Discharge Current
Automatic Feed Forward Compensation
Pulse-by-Pulse Current Limiting
Enhanced Load Response Characteristics
Under-Voltage Lockout With Hysteresis
Double Pulse Suppression
High Current Totem Pole Output
Internally Trimmed Bandgap Reference
500kHz Operation
Low RO Error Amp

Description

The UC1842A/3A/4A/5A family of control ICs is a pin for pin compatible improved version of the UC3842/3/4/5 family. Providing the necessary features to control current mode switched mode power supplies, this family has the following improved features. Start up current is guaranteed to be less than 0.5mA. Oscillator discharge is trimmed to 8.3mA. During under voltage lockout, the output stage can sink at least 10mA at less than 1.2V for V_CC over 5V.

Pricing / Packaging / CAD Design Tools / Samples

			Price	Packaging			CAD Design Tools		Samples
Device	Status	Temp (^oC)	Price \| Quantity	Package \| Pins	Top Side Marking	Package QTY \| Package Carrier	Symbols	Footprints	Samples
UC3843AD	ACTIVE	0 to 70	0.85 \| 1ku	SOIC (D) \| 14	View	50 \| TUBE
UC3843AD8	ACTIVE	0 to 70	0.85 \| 1ku	SOIC (D) \| 8	View	75 \| TUBE
UC3843AD8G4	ACTIVE	0 to 70	0.85 \| 1ku	SOIC (D) \| 8	View	75 \| TUBE
UC3843AD8TR	ACTIVE	0 to 70	0.90 \| 1ku	SOIC (D) \| 8	View	2500 \| LARGE T&R	Purchase Samples
UC3843AD8TRG4	ACTIVE	0 to 70	0.90 \| 1ku	SOIC (D) \| 8	View	2500 \| LARGE T&R	Purchase Samples
UC3843ADG4	ACTIVE	0 to 70	0.85 \| 1ku	SOIC (D) \| 14	View	50 \| TUBE
UC3843ADTR	ACTIVE	0 to 70	0.90 \| 1ku	SOIC (D) \| 14	View	2500 \| LARGE T&R	Purchase Samples
UC3843ADTRG4	ACTIVE	0 to 70	0.90 \| 1ku	SOIC (D) \| 14	View	2500 \| LARGE T&R	Purchase Samples
UC3843AN	ACTIVE	0 to 70	0.85 \| 1ku	PDIP (P) \| 8	View	50 \| TUBE
UC3843ANG4	ACTIVE	0 to 70	0.85 \| 1ku	PDIP (P) \| 8	View	50 \| TUBE

* Suggested Resale Price per unit (USD) for BUDGETARY USE ONLY. For higher volume price quotes,prices in local currency or delivery quotes, please contact your local Texas Instruments Sales Office or Authorized Distributor.

Inventory

Reported Distributor Inventory as of 9:52 AM GMT, 20 Nov 2009
Region	Company	In Stock	Purchase
TI Lead Time*: 20 WeeksUC3843AD
Americas	Arrow	320
Americas	Rochester Electronics	329
Asia	Farnell Asia	560
Asia	WPI	73
Europe	Arrow Northern Europe	29
	Avnet-SILICA	50
	Farnell	160
Worldwide	Mouser Electronics	132
TI Lead Time*: 20 WeeksUC3843AD8
Americas	Arrow	725
	Avnet	8
	Rochester Electronics	>1k
Asia	WPI	68
Europe	Avnet-SILICA	450
Worldwide	DigiKey	3
TI Lead Time*: 20 WeeksUC3843AD8G4
Europe	EBV Elektronik	>1k
Worldwide	DigiKey	Available
TI Lead Time*: 20 WeeksUC3843AD8TR
Worldwide	DigiKey	Available
TI Lead Time*: 20 WeeksUC3843AD8TRG4
Worldwide	DigiKey	Available
TI Lead Time*: 20 WeeksUC3843ADG4
Americas	Rochester Electronics	>1k
Asia	Farnell Asia	410
Europe	EBV Elektronik	49
Europe	Farnell	401
Worldwide	Mouser Electronics	233
TI Lead Time*: 20 WeeksUC3843ADTR
Americas	Arrow	>1k
TI Lead Time*: 20 WeeksUC3843ADTRG4
None Reported View Distributors
TI Lead Time*: 20 WeeksUC3843AN
Americas	Avnet	>1k
	Newark	402
	Rochester Electronics	>1k
Asia	Farnell Asia	530
Europe	Abacus Polar	276
	Arrow Northern Europe	450
	Avnet-SILICA	>1k
TI Lead Time*: 20 WeeksUC3843ANG4
Europe	EBV Elektronik	>1k
Worldwide	Mouser Electronics	444
View all Distributors

** Lead time information is not available at this time. However, our information is updated daily so please check back with us soon. Please contact your preferred TI Authorized Distributor for additional information.

Quality & Lead (Pb)-Free Data

	Product Content				DPPM / MTBF / FIT Rate
Device	Eco Plan*	Lead / Ball Finish	MSL Rating / Peak Reflow	Details	Details
UC3843AD	Green (RoHS & no Sb/Br)	CU NIPDAU	Level-1-260C-UNLIM	View	View
UC3843AD8	Green (RoHS & no Sb/Br)	CU NIPDAU	Level-2-260C-1 YEAR	View	View
UC3843AD8G4	Green (RoHS & no Sb/Br)	CU NIPDAU	Level-2-260C-1 YEAR	View	View
UC3843AD8TR	Green (RoHS & no Sb/Br)	CU NIPDAU	Level-2-260C-1 YEAR	View	View
UC3843AD8TRG4	Green (RoHS & no Sb/Br)	CU NIPDAU	Level-2-260C-1 YEAR	View	View
UC3843ADG4	Green (RoHS & no Sb/Br)	CU NIPDAU	Level-1-260C-UNLIM	View	View
UC3843ADTR	Green (RoHS & no Sb/Br)	CU NIPDAU	Level-1-260C-UNLIM	View	View
UC3843ADTRG4	Green (RoHS & no Sb/Br)	CU NIPDAU	Level-1-260C-UNLIM	View	View
UC3843AN	Green (RoHS & no Sb/Br)	CU NIPDAU	N/A for Pkg Type	View	View
UC3843ANG4	Green (RoHS & no Sb/Br)	CU NIPDAU	N/A for Pkg Type	View	View

* The planned eco-friendly classification: Pb-Free (RoHS) or Pb-Free (RoHS Exempt) or Green (RoHS & no Sb/Br) - please click on the Product Content Details "View" link in the table above for the latest availability information and additional product content details.

If the information you are requesting is not available online at this time, contact one of our Product Information Centers regarding the availability of this information.

Technical Documents

Most useful technical documents for UC3843A

Datasheet

Current Mode PWM Controller (Rev. B) (PDF, 3638 KB)
04 Sep 2009

Application Notes

Conditioning a Switch-mode Power Supply Current Signal Using TI Op Amps (HTM, 8 KB) 6704 views
23 Mar 2000 Read Abstract
Understanding Buck-Boost Power Stages in Switchmode Power Supplies (Rev. A) (HTM, 8 KB) 23186 views
28 May 2002 Read Abstract
UCC38C42 Family of High-Speed BiCMOS Current-Mode PWM Controllers (HTM, 8 KB) 11083 views
07 Feb 2002 Read Abstract
U-111, Practical Considerations in Current Mode Power Supplies (HTM, 8 KB) 11926 views
05 Sep 1999 Read Abstract
DN-40 The Effects of Oscillator Discharge Current Variations on Maximum Duty (HTM, 8 KB) 3179 views
05 Sep 1999 Read Abstract
DN-26 UC3842A Low-Cost Start-up and Fault Protection Circuit (HTM, 8 KB) 7362 views
05 Sep 1999 Read Abstract
DN-27 UC1842/UC1842A Family - Summary of Functional Differences (HTM, 8 KB) 3777 views
05 Sep 1999 Read Abstract
DN-29 UC3842A Family - Frequency Foldback Technique Provides Protection (HTM, 8 KB) 3567 views
05 Sep 1999 Read Abstract
DN-30 Programmable Electronic Circuit Breaker (HTM, 8 KB) 3068 views
05 Sep 1999 Read Abstract
DN-42A Design Considerations for Transitioning from UC3842 to the New UCC3802 (HTM, 8 KB) 5710 views
05 Sep 1999 Read Abstract

View Application Notes for PWM Power Supply Controllers

Customers Who Evaluated This Product Also Evaluated...
Part #	Name	Product Family	Comments
TL494	PWM Control Circuit	AC/DC AND DC/DC POWER SUPPLIES-PWM POWER SUPPLY CONTROLLERS	TI customers also evaluated this product.
UC3845A	Current Mode PWM Controller	AC/DC AND DC/DC POWER SUPPLIES-PWM POWER SUPPLY CONTROLLERS	TI customers also evaluated this product.
UCC28600	8-Pin Quasi Resonant Flyback Green Mode Controller	AC/DC AND DC/DC POWER SUPPLIES-PWM POWER SUPPLY CONTROLLERS	TI customers also evaluated this product.
UC3843	Current-Mode PWM Controller	AC/DC AND DC/DC POWER SUPPLIES-PWM POWER SUPPLY CONTROLLERS	TI customers also evaluated this product.
TPS54231	2A, 28V Input, 570 kHz Step Down SWIFT™ DC/DC Converter with Eco-Mode ™	DC/DC CONVERTERS (INTEGRATED SWITCH)-STEP-DOWN REGULATORS	TI customers also evaluated this product.
TPS54620	4.5V to 17V Input, 6A Synchronous Step Down SWIFT™ Converter	DC/DC CONVERTERS (INTEGRATED SWITCH)-STEP-DOWN REGULATORS	TI customers also evaluated this product.
TL431A	Adjustable Precision Shunt Regulator	VOLTAGE REFERENCE-SHUNT VOLTAGE REFERENCE	TI customers also evaluated this product.
TLV1117-33	Single Output LDO, 800mA, Fixed(3.3), Internal Current limit, Thermal Overload Protection	LINEAR REGULATORS-STANDARD VOLTAGE REGULATORS	TI customers also evaluated this product.
UCC28070	Two-Phase Interleaved CCM PFC Controller	AC/DC AND DC/DC POWER SUPPLIES-POWER FACTOR CORRECTION ICS	TI customers also evaluated this product.
TLV431A	Low Voltage Adjustable Precision Shunt Regulator	VOLTAGE REFERENCE-SHUNT VOLTAGE REFERENCE	TI customers also evaluated this product.

UC3843A Status: ACTIVE

Current Mode PWM Controller

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Datasheet

Functional Block Diagram

Other qualified versions of UC3843A

Customers Who Evaluated This Product Also Evaluated

Product Information

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Description

Pricing / Packaging / CAD Design Tools / Samples

Inventory

Quality & Lead (Pb)-Free Data

Technical Documents

Datasheet

Application Notes

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