Texas Instruments UCC3583QTR, UCC3583Q, UCC3583N, UCC3583DTR, UCC3583D Datasheet

UCC1583

UCC2583

UCC3583

Switch Mode Secondary Side Post Regulator

FEATURES

∙Precision Secondary Side Post Regulation for Multiple Output Power Supplies

∙Useful for Both Single Ended and Center Tapped Secondary Circuits

∙Ideal Replacement for Complex Magnetic Amplifier Regulated Circuits

∙Leading Edge Modulation

∙Does Not Require Gate Drive Transformer

∙High Frequency (>500kHz) Operation

∙Applicable for Wide Range of Output Voltages

∙High Current Gate Driver (0.5A Sink/1.5A Source)

∙Average Current Limiting Loop

DESCRIPTION

The UCC3583 is a synchronizable secondary side post regulator for precision regulation of the auxiliary outputs of multiple output power supplies. It contains a leading edge pulse width modulator, which generates the gate drive signal for a FET power switch connected in series with the rectifying diode. The turn-on of the power switch is delayed from the leading edge of the secondary power pulse to regulate the output voltage. The UCC3583 contains a ramp generator slaved to the secondary power pulse, a voltage error amplifier, a current error amplifier, a PWM comparator and associated logic, a gate driver, a precision reference, and protection circuitry.

The ramp discharge and termination of the gate drive signal are triggered by the synchronization pulse, typically derived from the falling edge of the transformer secondary voltage. The ramp starts charging again once its low threshold is reached. The gate drive signal is turned on when the ramp voltage exceeds the control voltage. This leading edge modulation technique prevents instability when the UCC3583 is used in peak current mode primary controlled systems.

The controller operates from a floating power supply referenced to the output voltage being controlled. It features an undervoltage lockout (UVLO) circuit, a soft start circuit, and an averaging current limit amplifier. The current limit can be programmed to be proportional to the output voltage, thus achieving foldback operation to minimize the dissipation under short circuit conditions.

(continued)

TYPICAL APPLICATION AND BLOCK DIAGRAM

Note: Pin connections shown for 14-pin packages.

UDG-96201-2

11/98

VSYNC

ISYNC

VDD

IVDD

ABSOLUTE MAXIMUM RATINGS

. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 15V

. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 15mA

RAMP . . . . . . . . . . . . . . . . . . . . . . . . . . . . . –0.3V to VDD + 1V IRAMP . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5mA IREF . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . –30mA PCOM . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . –0.2V to 0.2V

IGATE (twp < 1μS and Duty Cycle < 10%) . . . . . . –0.8A to 1.8A ICOMP . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . –5mA to 5mA ICAO . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . –5mA to 5mA

. . . . . . . . . . . . . . . . . . . . . . . . . . . . –0.6V to VREF +0.3V

. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . –05mA to 5mA INV, SS, ILIM, ISENSE. . . . . . . . . . . . . . –0.3V to VREF + 0.3V Storage Temperature . . . . . . . . . . . . . . . . . . . –65°C to +150°C Junction Temperature. . . . . . . . . . . . . . . . . . . –55°C to +150°C Lead Temperature (Soldering, 10 sec.) . . . . . . . . . . . . . +300°C

All voltages are with respect to the COM terminal unless otherwise stated. Currents are positive into, negative out of the specified terminal. Consult Packaging Section of Databook for thermal limitations and considerations of packages.

UCC1583

UCC2583

UCC3583

CONNECTION DIAGRAMS

DIL-14, SOIC-14 (Top View)

J, N, or D Packages

PLCC-20 (Top View)

Q Package

ELECTRICAL CHARACTERISTICS: Unless otherwise stated, these specifications apply for TA = –55°C to 125°C for UCC1583, –40°C to 85°C for UCC2583, and 0°C to 70°C for UCC3583; VDD = 12V, R T = 60k, CT = 200pF, TA = TJ.

PARAMETER	TEST CONDITIONS	MIN	TYP	MAX	UNITS
Ramp Generation and Synchronization
Maximum Input Operating Frequency	For input with 5% to 90% duty cycle (Note 1)	500			kHz
Ramp Frequency, Free Running		95	100	105	kHz
Ramp Discharge Current	VRAMP = 0.5V	2.0	3.6		mA
Low Threshold Voltage	No min, no max, 0=TYP		0		V
High Threshold Voltage		3.75	4	4.25	V
Synchronizing Threshold Voltage (On)	(Note 1)		1		V
Synchronizing Comparator Hysteresis			1		V
Output Duty Cycle
Minimum Duty Cycle	Output D/C = Output PW / Input PW			0	%
Maximum Duty Cycle	Output D/C = Output PW / Input PW	100			%

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UCC1583

UCC2583

UCC3583

ELECTRICAL CHARACTERISTICS: Unless otherwise stated, these specifications apply for TA = –55°C to 125°C for UCC1583, –40°C to 85°C for UCC2583, and 0°C to 70°C for UCC3583; VDD = 12V, R T = 60k, CT = 200pF, TA = TJ.

PARAMETER	TEST CONDITIONS	MIN	TYP	MAX	UNITS
Voltage Error Amplifier
VINV	VCOMP = VINV, 0°C to 70°C (UCC3583)	2.462	2.5	2.538	V
	VCOMP = VINV, All Other Temperature Ranges	2.45	2.5	2.55	V
IINV	VCOMP = VINV		300	500	nA
VCOMP Low	VINV = 2.6V, ICOMP = 100μA		450	700	mV
VCOMP High	VINV = 2.4V, ICOMP = –100μA	5.0	5.5	6.0	V
AVOL	No Load	70	90		dB
GBW Product	At f = 100kHz, TA = 25°C (Note 1)	3	5		MHz
Current Error Amplifier
Input Offset Voltage				10	mV
Input CM Low	Common Mode for CS and ILIM (Note 1)			0	V
Input CM High	Common Mode for CS and ILIM (Note 1)	2			V
VCAO Low	V+IN = 0V, V–IN = 0.1V, ICAO = 100μA		250	500	mV
VCAO High	V+IN = 0V, V–IN = 0.1V, ICAO = –100μA	5.0	5.5	6.0	V
Input Current (ILIM and CS Pins)		–50	0	50	nA
AVOL	No Load	70	90		dB
GBW Product	At f = 100kHz, TA = 25°C	2	4		MHz
Soft Start Current			10	25	μA
UVLO
VDD On Threshold Voltage		8.5	9.0	9.5	V
VDD Off Threshold Voltage		7.9	8.4	8.9	V
UVLO Hysteresis		0.3	0.6	0.9	V
Bias Supply
Supply Clamp Voltage		13	14	15	V
Supply Current (VDD)	f = 100kHz With No Gate Output Load		3	5	mA
Output Driver
VSAT High	IGATE = –150mA		0.6	1.0	V
VSAT Low	IGATE = 50mA		0.4	0.75	V
Rise Time	CGATE = 1nF		50	75	ns
Fall Time	CGATE = 330pF		20	40	ns
Reference
VREF	IREF = 0, 0°C to 70°C (UCC3583)	4.925	5	5.075	V
	IREF = 0, All Other Temperature Ranges	4.900	5	5.100	V
Line Regulation	VDD = 10V to 14V		2	30	mV
Load Regulation	IREF = 0mA to 2mA		1	20	mV

Note 1: Guaranteed by design. Not 100% tested in production.

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