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Details, datasheet, quote on part number:5962-9326501VCA
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Datasheet text preview:
UC1832 UC2832/3 UC3832/3
Precision Low Dropout Linear Controllers
FEATURES
· · · · · · Precision 1% Reference Over-Current Sense Threshold Accurate to 5% Programmable Duty-Ratio Over-Current Protection 4.5 V to 36 V Operation 100mA Output Drive, Source, or Sink Under-Voltage Lockout
DESCRIPTION
The UC2832 and UC3833 series of precision linear regulators include all the control functions required in the design of very low dropout linear regulators. Additionally, they feature an innovative duty-ratio current limiting technique which provides peak load capability 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 sinking or foldback current limiting. Additionally, if the timer pin is grounded, the duty-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 UC3833 family includes the basic functions of this design in a low-cost, 8pin mini-dip package, while the UC2832 series provides added versatility with the availability of 14 pins. Packaging options include plastic (N suffix), or ceramic (J suffix). Specified operating temperature ranges are: commercial (0°C to 70°C), order UC3832/3 (N or J); and industrial (40°C to 85°C), order UC2832/3 (N or J). Surface mount packaging is also available.
Additional Features of the UC2832 series: · · · · · Adjustable Current Limit to Current Sense Ratio Separate +VIN terminal Programmable Driver Current Limit Access to VREF and E/A(+) Logic-Level Disable Input
BLOCK DIAGRAMS
UDG-92040
SLUS387A - JUNE 1994 - REVISED - MAY 2003
UC1832 UC2832/3 UC3832/3 ABSOLUTE MAXIMUM RATINGS
Supply Voltage +VIN . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 40V Driver Output Current (Sink or Source) . . . . . . . . . . . . . 450mA Driver Sink to Source Voltage . . . . . . . . . . . . . . . . . . . . . . . 40V TRC Pin Voltage. . . . . . . . . . . . . . . . . . . . . . . . . . 0.3V to 3.2V Other Input Voltages. . . . . . . . . . . . . . . . . . . . . . . 0.3V to +VIN Operating Junction Temperature (note 2) . . . 55°C to +150°C Storage Temperature . . . . . . . . . . . . . . . . . . . 65°C to +150°C Lead Temperature (Soldering, 10 Seconds) . . . . . . . . . . 300°C
Note 1: Unless otherwise indicated, voltages are referenced to ground and currents are positive into, negative out of, the specified terminals. Note 2: See Unitrode Integrated Circuits databook for information regarding thermal specifications and limitations of packages.
CONNECTION DIAGRAMS UC2832
DIL-14 (Top View) J Or N Package DIL-8 (Top View) J Or N Package
UC3833
SOIC-16 (Top View) DW Package
SOIC-16 (Top View) DW Package
LCC-20 & PLCC-20 L & Q Package (Top View)
PACKAGE PIN FUNCTION
FUN CTION PIN
N/C +VIN Comp/Shutdown E/A(+) +2V REF N/C Gnd Logic Disable Limit Source N/C E/A(-) Sink VADJ N/C Timer RC Current Sense(-) Current Sense(+)
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15-17 18 19 20
LCC-20 & PLCC-20 L & Q Package (Top View)
PACKAGE PIN FUNCTION
FUN CTION PIN
+VIN & C/S(+) N/C N/C N/C Comp/Shutdown Gnd N/C N/C N/C Source N/C E/A(-) N/C N/C Sink Timer RC Current Sense(+) N/C
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18-20
2
UC1832 UC2832/3 UC3832/3 ELECTRICAL CHARACTERISTICS: Unless otherwise stated, specifications hold for
TA = 0°C to 70°C for the UC3832/3, 40°C to 85°C for the UC2832/3, +VIN = 15V, Driver sink = +VIN, C/S(+) voltage = +VIN. TA=TJ. TEST CONDITIONS +VIN = 6 V +VIN = 36 V Logic Disable = 2 V (UCx832 only) Reference Section Output Voltage (Note 3) Load Regulation (UCx832 only) Line Regulation Under-Voltage Lockout Threshold Logic Disable Input (UCx832 only) Threshold Voltage Input Bias Current Current Sense Section Comparator Offset Over Temperature Amplifier Offset (UCx833 only) Amplifier Offset (UCx832 only) VADJ = Open VADJ = 1 V VADJ = 0 V Input Bias Current Input Offset Current (UCx832 only) Amplifier CMRR (UCx832 only) Transconductance VADJ Input Current (UCx832 only) Timer Inactive Leakage Current Active Pullup Current Duty Ratio (note 4) Period (notes 4,5) Upper Trip Threshold (Vu) Lower Trip Threshold (Vl) Trip Threshold Ratio Error Amplifier Input Offset Voltage (UCx832 only) Input Bias Current Input Offset Current (UCx832 only) AVOL CMRR (UCx832 only) PSRR (UCx832 only) Transconductance VOH VOL IOH VCM = VCOMP = 2 V VCM = VCOMP = 2 V VCM = VCOMP = 2 V VCOMP = 1 V to 13 V VCM = 0V to +VIN - 3 V VCM = 2 V, +VIN = 4.5 V to 36 ICOMP = ±10 µA ICOMP = 0, Volts below +VIN ICOMP = 0 VCOMP = 2 V -700 -8.0 -4.5 -1.5 50 60 70 80 90 43 . .95 .45 -500 1.3 0.7 -100 -1.1 1.5 8.0 mV µA µA dB dB dB mS V V µA Vu/Vl C/S(+) = C/S(-) = +VIN; TRC pin = 2 V C/S(+) = +VIN, C/S(-) = +VIN - 0.4V; TRC pin = 0 V ontime/period, RT = 200k, CT = 0.27µF ontime + offtime, RT = 200k, CT = 0.27µF -345 0.25 -270 4.8 36 1.8 0.9 2.0 1.0 -175 µA µA % ms V V V/V VCM = +VIN VCM = +VIN VCM = 4.1 V to + VIN + 0.3 ICOMP = ±100 µA VADJ = 0V -10 95 93 110 110 180 250 65 -10 80 6 5 -1 100 100 135 135 235 305 100 105 107 170 170 290 360 135 10 mV mV mV mV mV mV µA µA dB mS µA Logic Disable = 0 V 1.3 -5.0 1.4 -1.0 1.5 V µA TJ = 25°C, IDRIVER = 10 mA over temperature, IDRIVER = 10 mA IO = 0 to 10 m +VIN = 4.5 V to 36 V, IDRIVER = 10 m 1.98 1.96 -10 2.00 2.00 -5.0 0.033 3.6 2.02 2.04 0.5 4.5 V V mV mV/V V MIN TYP 6.5 9.5 3.3 MAX 10 15 UNITS mA mA mA
PARAMETER Input Supply Supply Current
3
UC1832 UC2832/3 UC3832/3 ELECTRICAL CHARACTERISTICS (cont.) Unless otherwise stated, specifications hold for TA = 0°C to 70°C for the UC3832/3, 40°C to
85°C for the UC2832/3, +VIN = 15 V, Driver sink = +VIN, C/S(+) voltage = +VIN. TA=TJ. TEST CONDITIONS VCOMP = 2 V, C/S(-) = +VIN VCOMP = 2 V, C/S(-) = +VIN - 0.4 V Driver Limit & Source pins common; TJ = 25°C Over Temperature Limiting Voltage (UCx832 only) Internal Current Sense Resistance Pull-Up Current at Driver Sink Driver Limit to Source voltage at current limit, ISOURCE = -10 mA; TJ = 25°C (Note 6) TJ = 25°C (Note 6) Compensation/Shutdown = 0.4 V; Driver Sink = +VIN - 1V Compensation/Shutdown = 0.4 V, +VIN = 36 V; Driver Sink = 35 V Pull-Down Current at Driver Source Saturation Voltage Sink to Source Maximum Source Voltage UVLO Sink Leakage Maximum Reverse Source Voltage Compensation/Shutdown = 0.4 V; Driver Source = 1 V Driver Source = 0 V; Driver Current = 100 mA Driver Sink = +VIN, Driver Current = 100 mA Volts below + VIN +VIN = C/S(+) = C/S(-) = 2.5 V, Driver Sink = 15 V, Driver Source = 0 V, TA = 25°C Compensation/Shutdown = 0 V; ISOURCE = 100 µA, +VIN = 3 V 1.6 V 25 µA 3.0 V -800 -1000 150 .72 2.4 -300 -300 300 1.5 -100 -75 700 V µA µA µA V MIN 100 2 200 100 TYP 500 6 300 300 400 450 MAX 700 PARAMETER Error Amplifier (cont.) IOL Driver Maximum Current mA mA µA mA UNITS
Thermal Shutdown 160 °C Note 3: On the UCx833 this voltage is defined as the regulating level at the error amplifier inverting input, with the error amplifier driving VSOURCE to 2 V. Note 4: These parameters are first-order supply-independent, however both may vary with supply for +VIN less than about 4 V. This supply variation will cause a slight change in the timer period and duty cycle, although a high off-time/on-time ratio will be maintained. Note 5: With recommended RT value of 200k, TOFF RT CT * ln(Vu/Vl) ±10%. Note 6: The internal current limiting voltage has a temperature dependence of approximately -2.0 mV/°C, or -2800 ppm/°C. The internal 2.4 sense resistor has a temperature dependance of approximately +1500 ppm/°C.
APPLICATION AND OPERATION INFORMATION
NPN Pass (Local 100mA Regulator) (UCx833)
UDG-92041-1
4
APPLICATION AND OPERATION INFORMATION (cont.)
PNP Pass (Low Drop-Out Regulator) (UCx833)
UC1832 UC2832/3 UC3832/3
UDG-92042-1
NPN Pass (Medium Power, Low Drop-Out Regulator) (UCx832)
UDG-92043-1
Estimating Maximum Load Capacitance For any power supply, the rate at which the total output Current Sense Amplifier Offset Voltage and K= capacitance can be charged depends on the maximum 100mA output current available and on the nature of the load. For 1.35 for UCx833, and is variable from 1.35 to 3.05 a constant-current current-limited power supply, the outwith VADJ for the UCx832. put will come up if the load asks for less than the maxiFor a worst-case constant-current load of value just less mum available short-circuit limit current. than ITH, CMAX can be estimated from: To guarantee recovery of a duty-ratio current-limited TON CMAX = ((K-1)ITH) ( ), power supply from a short-circuited load condition, there VOUT is a maximum total output capacitance which can be where VOUT is the nominal regulator output voltage. charged for a given unit ON time. The design value of ON time can be adjusted by changing the timing capacitor. For a resistive load of value RL, the value of CMAX can be estimated from: Nominally, TON = 0.693 x 10k x CT. TON 1 CMAX = · . Typically, the IC regulates output current to a maximum of RL VOUT In [(1- ) -1] IMAX = K x ITH, where ITH is the timer trip-point current, K · ITH · RL 5
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