Texas Instruments UC2832J, UC2832DWTR, UC2832DW Datasheet

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BLOCK DIAGRAMS

• Precision 1% Reference

• Over-Current Sense Threshold

Accurate to 5%

• Programmable Duty-Ratio
Over-Current Protection

• 4.5V to 36V Operation

• 100mA Output Drive, Source or

Sink

• Under-Voltage Lockout

Additional Features of the UC1832
series:

• Adjustable Current Limit to
Current Sense Ratio

• Separate +V

IN terminal

• Programmable Driver Current
Limit

• Access to V

REF

and E/A(+)

• Logic-Level Disable Input

The UC1832 a nd UC18 33 series of precisio n line ar regulato rs includ e all the
control functions re quired in the design o f very low dropout linear regulators.
Additionally, they feature an innovative duty-ratio current limiting technique
which provides peak load capab ility while limiting the average power dissipa­tion of the external pass transistor during fault conditions. When the load cur­rent reaches an accurately programmed threshold, a gated-astable timer is
enabled, which switches the regulator’s pass device off and on at an externally
programmable duty-ratio. During the on-time of the pass element, the output
current is limited to a value slightly higher than the trip threshold of the duty-ra­tio timer. The constant-current-limit is programmable on the UCx832 to allow
higher peak current during the on-time of the pass device. With duty-ratio con­trol, high initial load demands and short circuit protection may both be accom­modated without extra heat sinki ng or foldback current limiting. Additionally, if
the timer pin is grounded, the du ty-ratio timer is disabled, and the IC operates
in constant-voltage/constant-current regulating mode.

These IC’s include a 2 Volt (±1%) reference, error amplifier, UVLO, and a high
current driver that has both source and sink outputs, allowing the use of either
NPN or PNP external pass transistors. Safe operation is assured by the inclu­sion of under-voltage lockout (UVLO) and thermal shutdown.

The UC1833 family includes the basic functions of this design in a low-cost, 8­pin mini-di p package , whi le the UC 1832 seri es provides added versatility with
the availability o f 14 pins. Packagi ng options include plastic (N suffix), or ce­ramic (J suffix). Specified opera ting tempe rature ranges are: commercial (0°C
to 70°C), order UC3832/3 (N or J); industrial (–25°C to 85°C), order UC2832/3
(N or J); and military (–55°C to 125°C), order UC1832/3J. Surface mount
packaging is also available.

UC1832/3
UC2832/3
UC3832/3

Precision Low Dropout Linear Controllers

FEATURES DESCRIPTION

UDG-92040

CONNECTION DIAG RAMS

DIL-14 (Top Vi ew )
J Or N Package

SOIC-16 (Top View)
DW Package

UC1832/3
UC2832/3
UC3832/3

PACKAGE PIN FUNCTION

FUNCTION PIN

N/C 1
+V

IN 2

Comp/Shutdown 3
E/A(+) 4
+2V REF 5
N/C 6
Gnd 7
Logic Disable 8
Limit 9
Source 10
N/C 11
E/A(-) 12
Sink 13
V

ADJ 14

N/C 15-17
Timer RC 18
Current Sense(- ) 19
Current Sense(+) 20

LCC-20 & PLCC-20
L & Q Package
(Top View)

ABSOLUTE MAXIMUM RATINGS

Supply Voltage +VIN. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 40V

Driver Output Curren t (S ink or Source) . . . . . . . . . . . . . 450mA

Driver Sink to Source Voltage . . . . . . . . . . . . . . . . . . . . . . . 40V

TRC Pin Voltage. . . . . . . . . . . . . . . . . . . . . . . . . . –0. 3V to 3.2V

Other Input Vol tages. . . . . . . . . . . . . . . . . . . . . . . –0.3V t o +V

IN

Operating Jun ctio n Tem per atur e (no te 2) . . . –55°C to +150° C

Storage Temperature. . . . . . . . . . . . . . . . . . . –65°C to +150°C

Lead Temperat ure (Solde ring, 10 Sec onds ) . . . . . . . . . . 300°C

Note 1: Unless otherwise indica te d, voltages ar e re feren ced t o
ground and curre nts are posit ive into , negat ive out of, the speci­fied terminals.
Note 2: See Unitrod e Inte gra ted C ircuit s datab ook f or
information regar ding t her m al specif icat ions an d limita tion s of
packages.

UC1832 UC1833

PACKAGE PIN FUNCTION

FUNCTION PIN

+VIN & C/S(+) 1
N/C 2
N/C 3
N/C 4
Comp/Shutdown 5
Gnd 6
N/C 7
N/C 8
N/C 9
Source 10
N/C 11
E/A(-) 12
N/C 13
N/C 14
Sink 15
Timer RC 16
Current Sense(+) 17
N/C 18-2 0

SOIC-16 (Top View)
DW Package

DIL-8 (Top View)
J Or N Package

LCC-20 & PLCC-20
L & Q Package
(Top View)

2

PARAMETER TEST CONDITIONS MIN TYP MAX UNITS

Input S u p pl y

Supply Curren t +V

IN = 6V 6.5 10 mA

+V

IN = 36V 9.5 15 mA

Logic Disable = 2V (UCx832 only) 3.3 mA

Reference Sect ion

Output Volta g e (Not e 3) T

J = 25°C, I DRIVER = 10mA 1.98 2.00 2.02 V

over temperature, I

DRIVER = 10mA 1.96 2.00 2.04 V

Load Regulat io n (UCx8 32 only) I

OUT = 0 to 10mA -10 -5.0 mV

Line Regulation +VIN = 4.5 to 36V, IDRIVER = 10mA 0.033 0.5 mV/V
Under-Voltage Lockout Threshold 3.6 4 .5 V

Logic Disabl e I npu t (UCx 832 on ly )

Threshold Volt age 1.3 1.4 1.5 V
Input Bias Current Logic Disable = 0V -5.0 -1.0 µA

Current Sense Section

Comparator Offset 95 100 105 mV

Over Temperature 93 100 107 mV
Amplifier Offset (UCx833 only) 110 135 170 mV
Amplifier Offset (UCx832 only) V

ADJ = Open 110 135 170 mV

V

ADJ = 1V 180 235 290 mV

V

ADJ = 0V 250 305 360 mV

Input Bias Current V

CM = +VIN 65 100 135 µA

Input Offset Current (UCx832 only) V

CM = +VIN -10 10 µA

Amplifier CMRR (UCx83 2 only) V

CM = 4.1V to +VIN+0.3V 80 dB

Transcon ductance I

COMP =

±

100µA65mS

VADJ Input Current (UCx832 only) VADJ = 0V -10 -1 µA

Timer

Inactive Leakage Current C/S(+) = C/S(-) = +V

IN; TRC pin = 2V 0.25 1.0 µA

Active Pullup Current C/S(+) = +V

IN, C/S(-) = +VIN - 0.4V; TRC pin = 0V -345 -270 -175 µA

Duty Ratio (not e 4) ontime/period , R

T = 200k, C T = 0.27µ F4.8 %

Period (not es 4, 5) ontime + offtime, R

T = 200k, CT = 0.27 µF 36 ms

Upper Trip Thr esh old (Vu) 1.8 V
Lower Trip Thresh old (Vl) 0.9 V
Trip Thresh old Rat io Vu/Vl 2.0 V/V

Error Amplifi er

Input Offset Voltage (UCx832 only) V

CM = VCOMP = 2 V -8.0 8.0 mV

Input Bias Current V

CM = VCOMP = 2 V -4.5 -1.1 µA

Input Offset Current (UCx832 only) V

CM = VCOMP = 2 V -1.5 1.5 µA

AVOL V

COMP = 1V to 13V 50 70 dB

CMRR (UCx832 only) V

CM = 0V to +VIN - 3V 60 80 dB

PSRR (UCx832 only) V

CM = 2V, +VIN = 4.5 to 36V 90 dB

Transcon duct ance ICOMP = ±10µA4.3mS
VOH I

COMP = 0, Volts below +V IN .95 1.3 V

VOL I

COMP = 0 .45 0.7 V

IOH V

COMP = 2V -700 -500 -100 µA

UC1832/3
UC2832/3
UC3832/3

Unless otherwise stated, specifications hold for TA = 0°C to 70°C for the
UC3832/3, –25°C to 85°C for the UC2832/3, and –55°C to 125°C for the
UC1832/3, +VIN = 15V, Driver sink = +V IN, C/S(+) voltage = +VIN. TA=TJ.

ELECTRICAL CHARACTERISTICS:

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