Texas Instruments

The UCC38083/4/5/6 is a family of BiCMOS pulse width modulation (PWM) controllers for dc-to-dc or off-line fixed-frequency current-mode switching power supplies. The dual output stages are configured for the push-pull topology. Both outputs switch at half the oscillator frequency using a toggle flip-flop. The dead time between the two outputs is typically 110 ns, limiting each output’s duty cycle to less than 50%. The new UCC3808x family is based on the UCC3808A architecture. The major differences include the addition of a programmable slope compensation ramp to the CS signal and the removal of the error amplifier. The current flowing out of the ISET pin through an external resistor is monitored internally to set the magnitude of the slope compensation function. This device also includes an internal discharge transistor from the CS pin to ground, which is activated at each clock cycle after the pulse is terminated. This discharges any filter capacitance on the CS pin during each cycle and helps minimize filter capacitor values and current sense delay. The UCC38083 and the UCC38084 devices have a typical soft-start interval time of 3.5 ms while the UCC38085 and the UCC38086 has less than 100 µs for applications where internal soft-start is not desired. The UCC38083 and the UCC38085 devices have the turn on/off thresholds of the 12.5 V / 8.3 V, while the UCC38084 and the UCC38086 has the turn on/off thresholds of 4.3 V / 4.1 V. Each device is offered in 8-pin TSSOP (PW), 8-pin SOIC (D) and 8-pin PDIP (P) packages. The UCC38083/4/5/6 is a family of BiCMOS pulse width modulation (PWM) controllers for dc-to-dc or off-line fixed-frequency current-mode switching power supplies. The dual output stages are configured for the push-pull topology. Both outputs switch at half the oscillator frequency using a toggle flip-flop. The dead time between the two outputs is typically 110 ns, limiting each output’s duty cycle to less than 50%. The new UCC3808x family is based on the UCC3808A architecture. The major differences include the addition of a programmable slope compensation ramp to the CS signal and the removal of the error amplifier. The current flowing out of the ISET pin through an external resistor is monitored internally to set the magnitude of the slope compensation function. This device also includes an internal discharge transistor from the CS pin to ground, which is activated at each clock cycle after the pulse is terminated. This discharges any filter capacitance on the CS pin during each cycle and helps minimize filter capacitor values and current sense delay. The UCC38083 and the UCC38084 devices have a typical soft-start interval time of 3.5 ms while the UCC38085 and the UCC38086 has less than 100 µs for applications where internal soft-start is not desired. The UCC38083 and the UCC38085 devices have the turn on/off thresholds of the 12.5 V / 8.3 V, while the UCC38084 and the UCC38086 has the turn on/off thresholds of 4.3 V / 4.1 V. Each device is offered in 8-pin TSSOP (PW), 8-pin SOIC (D) and 8-pin PDIP (P) packages.

The UCC28089 is a versatile BiCMOS controller for dc-to-dc or off-line fixed-frequency switching power supplies. The UCC28089 has dual alternating output stages in dual-alternating push-pull configuration. Both outputs switch at half the oscillator frequency using a toggle flip-flop and duty cycle is limited to less than 50%. The UCC28089 is optimized for use as the primary-side companion controller for a cascaded converter that has secondary-side control. The device incorporates dead-time programming. The synchronization output also provides dead-time information. The retry and soft-start duration scales with the oscillator clock frequency for high performance fault recovery. The UCC28089 also provides primary side under-voltage protection (UVLO), and over-current protection. Both the soft start and retry after fault durations scale with oscillator frequency for high performance. The turn-on/off UVLO thresholds are 10.5 V/8.0 V. The UCC28089 is a versatile BiCMOS controller for dc-to-dc or off-line fixed-frequency switching power supplies. The UCC28089 has dual alternating output stages in dual-alternating push-pull configuration. Both outputs switch at half the oscillator frequency using a toggle flip-flop and duty cycle is limited to less than 50%. The UCC28089 is optimized for use as the primary-side companion controller for a cascaded converter that has secondary-side control. The device incorporates dead-time programming. The synchronization output also provides dead-time information. The retry and soft-start duration scales with the oscillator clock frequency for high performance fault recovery. The UCC28089 also provides primary side under-voltage protection (UVLO), and over-current protection. Both the soft start and retry after fault durations scale with oscillator frequency for high performance. The turn-on/off UVLO thresholds are 10.5 V/8.0 V.

The UCC3809 family of BCDMOS economy low power integrated circuits contains all the control and drive circuitry required for off-line and isolated DC-to-DC fixed frequency current mode switching power supplies with minimal external parts count. Internally implemented circuits include undervoltage lockout featuring startup current less than 100µA, a user accessible voltage reference, logic to ensure latched operation, a PWM comparator, and a totem pole output stage to sink or source peak current. The output stage, suitable for driving N-Channel MOSFETs, is low in the off state. Oscillator frequency and maximum duty cycle are programmed with two resistors and a capacitor. The UCC3809 family also features full cycle soft start. The family has UVLO thresholds and hysteresis levels for off-line and DC-to-DC systems as shown in the table to the left. The UCC3809 and the UCC2809 are offered in the 8 pin SOIC (D), PDIP (N), TSSOP (PW), and MSOP (P) packages. The small TSSOP and MSOP packages make the device ideal for applications where board space and height are at a premium. The UCC3809 family of BCDMOS economy low power integrated circuits contains all the control and drive circuitry required for off-line and isolated DC-to-DC fixed frequency current mode switching power supplies with minimal external parts count. Internally implemented circuits include undervoltage lockout featuring startup current less than 100µA, a user accessible voltage reference, logic to ensure latched operation, a PWM comparator, and a totem pole output stage to sink or source peak current. The output stage, suitable for driving N-Channel MOSFETs, is low in the off state. Oscillator frequency and maximum duty cycle are programmed with two resistors and a capacitor. The UCC3809 family also features full cycle soft start. The family has UVLO thresholds and hysteresis levels for off-line and DC-to-DC systems as shown in the table to the left. The UCC3809 and the UCC2809 are offered in the 8 pin SOIC (D), PDIP (N), TSSOP (PW), and MSOP (P) packages. The small TSSOP and MSOP packages make the device ideal for applications where board space and height are at a premium.

The UCC3809 family of BCDMOS economy low power integrated circuits contains all the control and drive circuitry required for off-line and isolated DC-to-DC fixed frequency current mode switching power supplies with minimal external parts count. Internally implemented circuits include undervoltage lockout featuring startup current less than 100µA, a user accessible voltage reference, logic to ensure latched operation, a PWM comparator, and a totem pole output stage to sink or source peak current. The output stage, suitable for driving N-Channel MOSFETs, is low in the off state. Oscillator frequency and maximum duty cycle are programmed with two resistors and a capacitor. The UCC3809 family also features full cycle soft start. The family has UVLO thresholds and hysteresis levels for off-line and DC-to-DC systems as shown in the table to the left. The UCC3809 and the UCC2809 are offered in the 8 pin SOIC (D), PDIP (N), TSSOP (PW), and MSOP (P) packages. The small TSSOP and MSOP packages make the device ideal for applications where board space and height are at a premium. The UCC3809 family of BCDMOS economy low power integrated circuits contains all the control and drive circuitry required for off-line and isolated DC-to-DC fixed frequency current mode switching power supplies with minimal external parts count. Internally implemented circuits include undervoltage lockout featuring startup current less than 100µA, a user accessible voltage reference, logic to ensure latched operation, a PWM comparator, and a totem pole output stage to sink or source peak current. The output stage, suitable for driving N-Channel MOSFETs, is low in the off state. Oscillator frequency and maximum duty cycle are programmed with two resistors and a capacitor. The UCC3809 family also features full cycle soft start. The family has UVLO thresholds and hysteresis levels for off-line and DC-to-DC systems as shown in the table to the left. The UCC3809 and the UCC2809 are offered in the 8 pin SOIC (D), PDIP (N), TSSOP (PW), and MSOP (P) packages. The small TSSOP and MSOP packages make the device ideal for applications where board space and height are at a premium.

The UCC381-3/-5/-ADJ family of positive linear series pass regulators is tailored for low drop out applications where low quiescent power is important. Fabricated with a BiCMOS technology ideally suited for low input to output differential applications, the UCC381 will pass 1A while requiring only 0.5V of input voltage headroom. Dropout voltage decreases linearly with output current, so that dropout at 200mA is less than 100mV. Quiescent current is always less than 650uA. To prevent reverse current conduction, on-chip circuitry limits the minimum forward voltage to typically 50mV. Once the forward voltage limit is reached, the input-output differential voltage is maintained as the input voltage drops until undervoltage lockout disables the regulator. UCC381-3 and UCC381-5 versions have on-chip resistor networks preset to regulate either 3.3V or 5.0V, respectively. Furthermore, remote sensing of the load voltage is possible by connecting the VOUTS pin directly at the load. The output voltage is then regulated to 1.5% at room temperature and better than 2.5% over temperature. The UCC381-ADJ version has a regulated output voltage programmed by an external user-definable resistor ratio. Short circuit current is internally limited. The device responds to a sustained overcurrent condition by turning off after a TONdelay. The device then stays off for a period, TOFF, that is 32 times the TONdelay. The device then begins pulsing on and off at the TON/(TON+TOFF) duty cycle of 3%. This drastically reduces the power dissipation during short circuit such that heat sinking, if at all required, must only accommodate normal operation. On the fixed output versions of the device TON is fixed at 400us - a guaranteed minimum. On the adjustable version an external capacitor sets the on time. The off time is always 32 times TON. The UCC381 can be shutdown to 25uA (max) by pulling the CT pin low. Internal power dissipation is further controlled with thermal overload protection circuitry. Thermal shutdown occurs if the junction temperature exceeds 165°C. The chip will remain off until the temperature has dropped 20°C. The UCC281 series is specified for operation over the industrial range of -40°C to +85°C, and the UCC381 series is specified from 0°C to +70°C. These devices are available in the 8 pin DP surface mount power package. For other packaging options consult the factory. The UCC381-3/-5/-ADJ family of positive linear series pass regulators is tailored for low drop out applications where low quiescent power is important. Fabricated with a BiCMOS technology ideally suited for low input to output differential applications, the UCC381 will pass 1A while requiring only 0.5V of input voltage headroom. Dropout voltage decreases linearly with output current, so that dropout at 200mA is less than 100mV. Quiescent current is always less than 650uA. To prevent reverse current conduction, on-chip circuitry limits the minimum forward voltage to typically 50mV. Once the forward voltage limit is reached, the input-output differential voltage is maintained as the input voltage drops until undervoltage lockout disables the regulator. UCC381-3 and UCC381-5 versions have on-chip resistor networks preset to regulate either 3.3V or 5.0V, respectively. Furthermore, remote sensing of the load voltage is possible by connecting the VOUTS pin directly at the load. The output voltage is then regulated to 1.5% at room temperature and better than 2.5% over temperature. The UCC381-ADJ version has a regulated output voltage programmed by an external user-definable resistor ratio. Short circuit current is internally limited. The device responds to a sustained overcurrent condition by turning off after a TONdelay. The device then stays off for a period, TOFF, that is 32 times the TONdelay. The device then begins pulsing on and off at the TON/(TON+TOFF) duty cycle of 3%. This drastically reduces the power dissipation during short circuit such that heat sinking, if at all required, must only accommodate normal operation. On the fixed output versions of the device TON is fixed at 400us - a guaranteed minimum. On the adjustable version an external capacitor sets the on time. The off time is always 32 times TON. The UCC381 can be shutdown to 25uA (max) by pulling the CT pin low. Internal power dissipation is further controlled with thermal overload protection circuitry. Thermal shutdown occurs if the junction temperature exceeds 165°C. The chip will remain off until the temperature has dropped 20°C. The UCC281 series is specified for operation over the industrial range of -40°C to +85°C, and the UCC381 series is specified from 0°C to +70°C. These devices are available in the 8 pin DP surface mount power package. For other packaging options consult the factory.

The UCC3813-x device family of high-speed, low-power integrated circuits contains all of the control and drive components required for off-line and DC-to-DC fixed-frequency current-mode switching power supplies with minimal parts count. These devices have the same pin configuration as the UC384x device family, and also offer the added features of internal full-cycle soft start and internal leading-edge blanking of the current-sense input. The UCC3813-x device family offers a variety of package options, temperature-range options, choice of maximum duty cycle, and choice of critical voltage levels. Devices with lower reference voltage such as the UCC3813-3 and UCC3813-5 fit best into battery operated systems, while the higher reference and the higher UVLO hysteresis of the UCC3813-2 device and UCC3813-4 device make these ideal choices for use in off-line power supplies. The UCC2813-x device series is specified for operation from –40°C to 85°C and the UCC3813-x device series is specified for operation from 0°C to 70°C. The UCC3813-x device family of high-speed, low-power integrated circuits contains all of the control and drive components required for off-line and DC-to-DC fixed-frequency current-mode switching power supplies with minimal parts count. These devices have the same pin configuration as the UC384x device family, and also offer the added features of internal full-cycle soft start and internal leading-edge blanking of the current-sense input. The UCC3813-x device family offers a variety of package options, temperature-range options, choice of maximum duty cycle, and choice of critical voltage levels. Devices with lower reference voltage such as the UCC3813-3 and UCC3813-5 fit best into battery operated systems, while the higher reference and the higher UVLO hysteresis of the UCC3813-2 device and UCC3813-4 device make these ideal choices for use in off-line power supplies. The UCC2813-x device series is specified for operation from –40°C to 85°C and the UCC3813-x device series is specified for operation from 0°C to 70°C.

The UCC3813-x device family of high-speed, low-power integrated circuits contains all of the control and drive components required for off-line and DC-to-DC fixed-frequency current-mode switching power supplies with minimal parts count. These devices have the same pin configuration as the UC384x device family, and also offer the added features of internal full-cycle soft start and internal leading-edge blanking of the current-sense input. The UCC3813-x device family offers a variety of package options, temperature-range options, choice of maximum duty cycle, and choice of critical voltage levels. Devices with lower reference voltage such as the UCC3813-3 and UCC3813-5 fit best into battery operated systems, while the higher reference and the higher UVLO hysteresis of the UCC3813-2 device and UCC3813-4 device make these ideal choices for use in off-line power supplies. The UCC2813-x device series is specified for operation from –40°C to 85°C and the UCC3813-x device series is specified for operation from 0°C to 70°C. The UCC3813-x device family of high-speed, low-power integrated circuits contains all of the control and drive components required for off-line and DC-to-DC fixed-frequency current-mode switching power supplies with minimal parts count. These devices have the same pin configuration as the UC384x device family, and also offer the added features of internal full-cycle soft start and internal leading-edge blanking of the current-sense input. The UCC3813-x device family offers a variety of package options, temperature-range options, choice of maximum duty cycle, and choice of critical voltage levels. Devices with lower reference voltage such as the UCC3813-3 and UCC3813-5 fit best into battery operated systems, while the higher reference and the higher UVLO hysteresis of the UCC3813-2 device and UCC3813-4 device make these ideal choices for use in off-line power supplies. The UCC2813-x device series is specified for operation from –40°C to 85°C and the UCC3813-x device series is specified for operation from 0°C to 70°C.

The UCC3813-x device family of high-speed, low-power integrated circuits contains all of the control and drive components required for off-line and DC-to-DC fixed-frequency current-mode switching power supplies with minimal parts count. These devices have the same pin configuration as the UC384x device family, and also offer the added features of internal full-cycle soft start and internal leading-edge blanking of the current-sense input. The UCC3813-x device family offers a variety of package options, temperature-range options, choice of maximum duty cycle, and choice of critical voltage levels. Devices with lower reference voltage such as the UCC3813-3 and UCC3813-5 fit best into battery operated systems, while the higher reference and the higher UVLO hysteresis of the UCC3813-2 device and UCC3813-4 device make these ideal choices for use in off-line power supplies. The UCC2813-x device series is specified for operation from –40°C to 85°C and the UCC3813-x device series is specified for operation from 0°C to 70°C. The UCC3813-x device family of high-speed, low-power integrated circuits contains all of the control and drive components required for off-line and DC-to-DC fixed-frequency current-mode switching power supplies with minimal parts count. These devices have the same pin configuration as the UC384x device family, and also offer the added features of internal full-cycle soft start and internal leading-edge blanking of the current-sense input. The UCC3813-x device family offers a variety of package options, temperature-range options, choice of maximum duty cycle, and choice of critical voltage levels. Devices with lower reference voltage such as the UCC3813-3 and UCC3813-5 fit best into battery operated systems, while the higher reference and the higher UVLO hysteresis of the UCC3813-2 device and UCC3813-4 device make these ideal choices for use in off-line power supplies. The UCC2813-x device series is specified for operation from –40°C to 85°C and the UCC3813-x device series is specified for operation from 0°C to 70°C.

The UCCx817 and UCCx818 family provides all the functions necessary for active power factor-corrected preregulators. The controller achieves near-unity power factor by shaping the AC input line current waveform to correspond to that of the AC input line voltage. Average current mode control maintains stable, low distortion sinusoidal line current. Designed in Texas Instrument’s BiCMOS process, the UCCx817 and UCCx818 offers new features such as lower start-up current, lower power dissipation, overvoltage protection, a shunt UVLO detect circuitry, a leading-edge modulation technique to reduce ripple current in the bulk capacitor, and an improved, low-offset (±2-mV) current amplifier to reduce distortion at light load conditions. The UCCx817 and UCCx818 family provides all the functions necessary for active power factor-corrected preregulators. The controller achieves near-unity power factor by shaping the AC input line current waveform to correspond to that of the AC input line voltage. Average current mode control maintains stable, low distortion sinusoidal line current. Designed in Texas Instrument’s BiCMOS process, the UCCx817 and UCCx818 offers new features such as lower start-up current, lower power dissipation, overvoltage protection, a shunt UVLO detect circuitry, a leading-edge modulation technique to reduce ripple current in the bulk capacitor, and an improved, low-offset (±2-mV) current amplifier to reduce distortion at light load conditions.