UCC3912PWPTRG4


            SLUS241D − MARCH 1994 - REVISED NOVEMBER 2003 D Integrated 0.15-Ω Power MOSFET D 3-V to 8-V Operation D Digital Programmable Current Limit D D D D D D D D D from 0 A to 3 A Electronic Circuit Breaker Function 1µA ICC When Disabled Programmable On-Time Programmable Start Delay Fixed 3% Duty Cycle D Unidirectional Switch Thermal Shutdown Fault-Output Indicator Maximum-Output Current Can Be Set to 1 A Above the Programmed Fault Level or to a Full 4 A Power SOIC, Low-Thermal Resistance Packaging description The UCC3912 family of hot swap power managers provides complete power management, hot swap capability, and circuit breaker functions. The only component required to operate the device, other than supply bypassing, is the fault timing capacitor, CT. All control and housekeeping functions are integrated, and externally programmable. These include the fault current level, maximum output-sourcing current, maximum fault time, and startup delay. In the event of a constant fault, the internal fixed 3% duty cycle ratio limits average output power. The internal 4-bit DAC allows programming of the fault level current from 0 A to 3 A with 0.25-A resolution. The IMAX control pin sets the maximum sourcing current to 1 A above the fault level when driven low, and to a full 4 A when driven high for applications which require fast output capacitor charging. When the output current is below the fault level, the output MOSFET is switched on with a nominal on resistance of 0.15 Ω. When the output current exceeds the fault level, but is less than the maximum sourcing level, the output remains switched on, but the fault timer starts charging CT. Once CT charges to a preset threshold, the switch is turned off, and remains off for 30 times the programmed fault time. When the output current reaches the maximum sourcing level, the MOSFET transitions from a switch to a constant current source. (continued) block diagram H=4A IMAX 2 VIN 3 VIN 14 VOUT 15 VOUT 1 SHTDWN 10 + REVERSE VOLTAGE COMPARATOR CHARGE PUMP 30 mV − + V OUT CURRENT SENSE 4A POWER FET + MAX CURRENT LEVEL − LINEAR CURRENT AMPLIFIER H = OPEN 1A ABOVE FAULT CURRENT FAULT LEVEL 0A TO 3 A ON TIME CONTROL + − 3% DUTY CYCLE THERMAL SHUTDOWN OVERCURRENT COMPARATOR 0 A−3 A 0.25 RES INTERNAL BIAS 6 7 8 9 5 B3 B2 B1 B0 GND 4 BIT DAC 4 13 12 HEATSINK GND PINS 11 16 CT FAULT 1.5 V + − UDG-99146 Please be aware that an important notice concerning availability, standard warranty, and use in critical applications of Texas Instruments semiconductor products and disclaimers thereto appears at the end of this data sheet.  
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            SLUS241D − MARCH 1994 - REVISED NOVEMBER 2003 description (continued) The UCC3912 family is designed for unidirectional current flow, emulating an ideal diode in series with the power switch. This feature is particularly attractive in applications where many devices are powering a common bus, such as with SCSI Termpwr. The UCC3912 family can be put into sleep mode drawing only 1-µA of supply current. The SHTDWN pin has a preset threshold hysteresis which allows the user the ability to set a time delay upon startup to achieve sequencing of power. Other features include an open drain FAULT output indicator, thermal shutdown, under voltage lockout, and a low thermal resistance small outline package. absolute maximum ratings over operating free-air temperature (unless otherwise noted)†} VIN . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8 V FAULT sink current . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 50 mA FAULT voltage . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . -0.3 to VIN Output current . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Self Limiting Input voltage (B0, B1, B2, B3, IMAX, SHTDWN) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . -0.3 to VIN Storage temperature range, Tstg . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . -65°C to 150°C Operating junction temperature range, TJ . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . -55°C to 150°C Lead temperature (soldering, 10 sec.) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 300°C † Stresses beyond those listed under “absolute maximum ratings” may cause permanent damage to the device. These are stress ratings only, and functional operation of the device at these or any other conditions beyond those indicated under “recommended operating conditions” is not implied. Exposure to absolute-maximum-rated conditions for extended periods may affect device reliability. ‡ Currents are positive into, negative out of the specified terminal. Consult Packaging Section of the Interface Products Data book (TI Literature Number SLUD002) for thermal limitations and considerations of packages. package information TSSOP-24, PWP Package (TOP VIEW) DIL-16, SOIC-16 N, DP Package (TOP VIEW) SHTDWN1 *Pin 5 serves as lowest impedance to the electrical ground; Pins 4, 12, and 13 serve as heat sink/ground. These pins should be connected to large etch areas to help dissipate heat. For N package, pins 4, 12, and 13 are N/C. 2 24 FAULT N/C 2 23 N/C VIN 3 22 VOUT VIN 4 21 VOUT GND* 5 20 GND* GND* 6 19 GND* GND* 7 18 GND* GND* 8 17 GND* EGND* 9 16 GND* B3 10 15 CT B2 11 14 IMAX B1 12 13 B0 *Pin 9 serves as lowest impedance to the electrical ground; other GND pins serve as heat sink/ground. These pins should be connected to large etch areas to help dissipate heat. www.ti.com 

            SLUS241D − MARCH 1994 - REVISED NOVEMBER 2003 electrical characteristics, these specifications apply for TA = −40°C to 85°C for the UCC2912; TA = 0°C to 70°C for the UCC3912, VIN = 5 V, IMAX = 0.4 V, SHTDWN = 2.4 V (unless otherwise stated) supply section PARAMETER TEST CONDITIONS MIN Voltage input range TYP Supply current Sleep mode current MAX 3.0 SHTDWN = 0.2 V UNITS 8.0 V 1.0 2.0 mA 0.5 5.0 µA NOTE 1: All voltages are with respect to ground. Current is positive into and negative out of the specified terminal. output section PARAMETER TEST CONDITIONS MIN TYP IOUT = 1 A IOUT = 2 A IOUT = 3 A IOUT = 1A, MAX UNITS 0.15 0.22 V 0.3 0.45 V 0.45 0.68 V VIN = 3 V 0.17 0.27 V IOUT = 2 A, IOUT = 3 A, VIN = 3 V 0.35 0.56 V VIN = 3 V 0.5 0.8 V SHTDWN = 0.2 V, VOUT = 5 V 5 20 µA Initial startup time VIN < VOUT , See Note 2 Short circuit response See Note 2 100 ns Thermal shutdown See Note 2 170 °C Thermal hysteresis See Note 2 10 °C Voltage drop Reverse leakage current µs 100 NOTE 1: All voltages are with respect to ground. Current is positive into and negative out of the specified terminal. NOTE 2: Ensured by design. Not production tested. DAC section PARAMETER TEST CONDITIONS Output leakage Trip current Maximum output current Maximum output current over trip (current source mode) MIN TYP Code = 0000−0011 MAX 20 µA Code = 0100 0.1 0.25 0.45 A Code = 0101 0.25 0.50 0.75 A Code = 0110 0.5 0.75 1.0 A Code = 0111 0.75 1.00 1.25 A Code = 1000 1.0 1.25 1.5 A Code = 1001 1.25 1.50 1.75 A Code = 1010 1.5 1.75 2.0 A Code = 1011 1.7 2.00 2.3 A Code = 1100 1.9 2.25 2.58 A Code = 1101 2.1 2.50 2.9 A Code = 1110 2.3 2.75 3.2 A Code = 1111 2.5 3.0 Code = 0000 to 0011 UCC2912 Code = 0100 to 1111, UCC3912 Code = 0100 to 1111, Maximum output current (current source mode) UNITS 0 Code = 0100 to 1111, IMAX = 0 V IMAX = 0 V A mA 0.5 1.0 2.0 A 0.5 1.0 1.8 A 4.0 5.2 A IMAX = 2.4 V 3.0 NOTE 1: All voltages are with respect to ground. Current is positive into and negative out of the specified terminal. www.ti.com 3.5 0.02 3 

            SLUS241D − MARCH 1994 - REVISED NOVEMBER 2003 electrical characteristics, these specifications apply for TA = −40°C to 85°C for the UCC2912; TA = 0°C to 70°C for the UCC3912, VIN = 5 V, IMAX = 0.4 V, SHTDWN = 2.4 V (unless otherwise stated) timer section PARAMETER TEST CONDITIONS MIN TYP MAX UNITS VCT = 1.0 V VCT = 1.0 V −45.0 -36.0 −22.0 µA 0.72 1.20 1.57 µA VCT = 1.0 V VOUT = 0 V 0.72 1.20 1.50 µA 2.0 3.0 6.0 % CT fault threshold 1.3 1.5 1.7 V CT reset threshold 0.4 0.5 0.6 V CT charge current UCC2912 CT discharge current UCC3912 Output duty cycle NOTE 1: All voltages are with respect to ground. Current is positive into and negative out of the specified terminal. shutdown section PARAMETER TEST CONDITIONS Shutdown threshold MIN TYP 1.1 Shutdown hysteresis Input current MAX 1.5 UNITS 1.9 100 SHTDWN = 1 V 100 V mV 500 nA fault output section PARAMETER TEST CONDITIONS MIN TYP MAX Output leakage current Low level output voltage IOUT = 10 mA 0.4 UNITS 500 nA 0.8 V TTL input dc characteristics section PARAMETER TTL input voltage high TEST CONDITIONS (can be connected to VIN) MIN TYP MAX 2.0 V TTL input voltage low TTL input high current TTL input low current UNITS VIH = 2.4 V VIL = 0.4 V 3 0.8 V 10 µA 1 µA NOTE 1: All voltages are with respect to ground. Current is positive into and negative out of the specified terminal. pin description B0−B3: These pins provide digital input to the DAC which sets the fault current threshold. They can be used to provide a digital soft-start, adaptive current limiting. CT: A capacitor connected to ground sets the maximum fault time. The maximum fault time must be more than the time to charge the external capacitance in one cycle. The maximum fault time is defined as FAULT = 27.8 × 103 × CT. Once the fault time is reached the output will shutdown for a time given by: TSD = 833 × 103 × CT, this equates to a 3% duty cycle. FAULT: Open drain output which pulls low upon any condition which causes the output to open: fault, thermal shutdown, or shutdown. IMAX: When this pin is set to logic low the maximum sourcing current will always be 1 A above the programmed fault level. When set to logic high, the maximum sourcing current will be a constant 4 A for applications which require fast charging of load capacitance. 4 www.ti.com 

            SLUS241D − MARCH 1994 - REVISED NOVEMBER 2003 pin description (continued) SHTDWN: When this pin is brought to a logic low, the IC is put into a sleep mode drawing typically less than 1 µA of ICC. The input threshold is hysteretic, allowing the user to program a startup delay with an external RC circuit. VIN: Input voltage to the UCC3912. The recommended voltage range is 3 V to 8 V. Both VIN pins should be connected together and to the power source. VOUT: Output voltage from the UCC3912. When switched the output voltage will be approximately VIN − (0.15 Ω × IOUT). Both VOUT pins should be connected together and to the load. APPLICATION INFORMATION 4 VIN 2 R1 CIN 12 13 HEAT SINK GND PINS VIN 5 GND VOUT 3 D1 VOUT 14 15 RL UCC2912 UCC3912 LED S6 16 FAULT RSD VIN SHTDWN 1 11 CT CT COUT B3 B2 B1 B0 IMAX 6 7 8 9 10 CSD VIN S1 S2 S3 S4 S5 DIP SWITCH NOTE: For demonstration board schematic see Design Note DN-58 (TI Literature Number SLUA187). UDG-99171 Figure 1. Evaluation Circuit protecting the UCC3912 from voltage transients The parasitic inductance associated with the power distribution can cause a voltage spike at VIN if the load current is suddenly interrupted by the UCC3912. It is important to limit the peak of this spike to less than 8 V to prevent damage to the UCC3912. This voltage spike can be minimized by: D Reducing the power distribution inductance (e.g., twist the positive and negative leads of the power supply feeding VIN, locate the power supply close to the UCC3912, use a PCB ground plane,...etc.). D Decoupling VIN with a capacitor, CIN (refer to Figure 1), located close to pins 2 and 3. This capacitor is typically less than 1 µF to limit the inrush current. D Clamping the voltage at VIN below 8 V with a zener diode, D1 (refer to Figure 1), located close to pins 2 and 3. www.ti.com 5 

            SLUS241D − MARCH 1994 - REVISED NOVEMBER 2003 APPLICATION INFORMATION UDG-93019-4 Figure 2. Load Current, Timing-Capacitor Voltage, and Output Voltage of the UCC3912 Under Fault Conditions. estimating maximum load capacitance For hot-swap applications, the rate at which the total output capacitance can be charged depends on the maximum output current available and the nature of the load. For a constant-current current-limited controller, the output will come up if the load asks for less than the maximum available short-circuit current. To ensure recovery of a duty-cycle from a short-circuited load condition, there is a maximum total output capacitance which can be charged for a given unit ON time (fault time). The design value of ON or fault time can be adjusted by changing the timing capacitor CT. For worst-case constant-current load of value just less than the trip limit; COUT(max) can be estimated from: C OUT(max) ǒ MAX * ILOADǓ [ I ǒ 28 10 3 CT V OUT where VOUT is the output voltage. 6 www.ti.com Ǔ 

            SLUS241D − MARCH 1994 - REVISED NOVEMBER 2003 APPLICATION INFORMATION For a resistive load of value RL, the value of COUT(max) can be estimated from: ȡ ȧ ȧ ȧ ȧ ȧ ȧ C [ OUT(max) ȧ ȧ ȧ ȧ ȧRL ȧ ȧ Ȣ 10 3 28 ȡ ȧ ȏnȧ ȧ1 Ȣ * ǒ CT 1 V OUT I RL MAX ȣ ȧ ȧ ȧ ȧ ȧ ȧ ȧ ȣȧ ȧ ȧȧ ȧȧ ȧȧ ȧ ȤȤ Ǔ The overcurrent comparator senses both the DAC output and a representation of the output current. When the output current exceeds the programmed level the timing capacitor CT charges with 36 µA of current. If the fault occurs for the time it takes for CT to charge up to 1.5 V, the fault latch is set and the output switch is opened. The output remains opened until CT discharges to 0.5 V with a 1.2-µA current source. Once the 0.5 V is reached the output is enabled and will either appear as a switch, if the fault is removed, or a current source if the fault remains. If the over current condition is still present, then CT will begin charging, starting the cycle over, resulting in approximately a 3% on time. UDG-94019-1 Figure 3. UCC3912 On-Time Circuitry www.ti.com 7 

            SLUS241D − MARCH 1994 - REVISED NOVEMBER 2003 APPLICATION INFORMATION UDG-94019-1 Figure 4. RDS(on) vs. Temperature at 2-A Load Current. safety recommendations Although the UCC3912 family is designed to provide system protection for all fault conditions, all integrated circuits can ultimately fail short. For this reason, if the UCC3912 is intended for use in safety critical applications where UL or some other safety rating is required, a redundant safety device such as a fuse should be placed in series with the device. The UCC3912 will prevent the fuse from blowing virtually for all fault conditions, increasing system reliability and reducing maintenance cost, in addition to providing the hot swap benefits of the device. 8 www.ti.com PACKAGE OPTION ADDENDUM www.ti.com 14-Oct-2022 PACKAGING INFORMATION Orderable Device Status (1) Package Type Package Pins Package Drawing Qty Eco Plan (2) Lead finish/ Ball material MSL Peak Temp Op Temp (°C) (3) Device Marking Samples (4/5) (6) UCC2912DP ACTIVE SOIC D 16 40 RoHS & Green NIPDAU Level-2-260C-1 YEAR -40 to 85 UCC2912DP Samples UCC2912PWP ACTIVE TSSOP PW 24 60 RoHS & Green NIPDAU Level-2-260C-1 YEAR -40 to 85 UCC2912PWP Samples UCC3912DP ACTIVE SOIC D 16 40 RoHS & Green NIPDAU Level-2-260C-1 YEAR 0 to 70 UCC3912DP Samples UCC3912DPTR ACTIVE SOIC D 16 2500 RoHS & Green NIPDAU Level-2-260C-1 YEAR 0 to 70 UCC3912DP Samples UCC3912PWP ACTIVE TSSOP PW 24 60 RoHS & Green NIPDAU Level-2-260C-1 YEAR 0 to 70 UCC3912PWP Samples UCC3912PWPG4 ACTIVE TSSOP PW 24 60 RoHS & Green NIPDAU Level-2-260C-1 YEAR 0 to 70 UCC3912PWP Samples UCC3912PWPTR ACTIVE TSSOP PW 24 2000 RoHS & Green NIPDAU Level-2-260C-1 YEAR 0 to 70 UCC3912PWP Samples (1) The marketing status values are defined as follows: ACTIVE: Product device recommended for new designs. LIFEBUY: TI has announced that the device will be discontinued, and a lifetime-buy period is in effect. NRND: Not recommended for new designs. Device is in production to support existing customers, but TI does not recommend using this part in a new design. PREVIEW: Device has been announced but is not in production. Samples may or may not be available. OBSOLETE: TI has discontinued the production of the device. (2) RoHS: TI defines "RoHS" to mean semiconductor products that are compliant with the current EU RoHS requirements for all 10 RoHS substances, including the requirement that RoHS substance do not exceed 0.1% by weight in homogeneous materials. Where designed to be soldered at high temperatures, "RoHS" products are suitable for use in specified lead-free processes. TI may reference these types of products as "Pb-Free". RoHS Exempt: TI defines "RoHS Exempt" to mean products that contain lead but are compliant with EU RoHS pursuant to a specific EU RoHS exemption. Green: TI defines "Green" to mean the content of Chlorine (Cl) and Bromine (Br) based flame retardants meet JS709B low halogen requirements of