LTC3129-1 e lecTrical characTerisTics The l denotes the specifications which apply over the specified operatingjunction temperature range, otherwise specifications are at TA = 25°C (Note 2). Unless otherwise noted, VIN = 12V, VOUT = 5V. PARAMETERCONDITIONSMINTYPMAXUNITS VCC UVLO Threshold (Rising) l 2.1 2.25 2.42 V VCC UVLO Hysteresis 60 mV VCC Current Limit VCC = 0V l 4 20 60 mA VCC Back-Drive Voltage (Maximum) l 5.5 V VCC Input Current (Back-Driven) VCC = 5.5V (Switching) 2 4 mA VCC Leakage to VIN if VCC>VIN VCC = 5.5V, VIN = 1.8V, Measured on VIN –27 µA VOUT UV Threshold (Rising) l 0.95 1.15 1.35 V VOUT UV Hysteresis 150 mV VOUT Current – Shutdown RUN = 0V, VOUT = 15V Including Switch Leakage 10 100 nA VOUT Current – Sleep PWM = 0V, VOUT ≥ VREG VOUT/27 µA VOUT Current – Active PWM = VCC, VOUT = 15V (Note 4) 5 9 µA PGOOD Threshold, Falling Referenced to Programmed VOUT Voltage –5.5 –7.5 –10 % PGOOD Hysteresis Referenced to Programmed VOUT Voltage 2.5 % PGOOD Voltage Low ISINK = 1mA 250 300 mV PGOOD Leakage PGOOD = 15V 1 50 nA Note 1: Stresses beyond those listed under Absolute Maximum Ratings Note 3: Specification is guaranteed by design and not 100% tested in may cause permanent damage to the device. Exposure to any Absolute production. Maximum Rating condition for extended periods may affect device Note 4: Current measurements are made when the output is not switching. reliability and lifetime. Note 5: This IC includes overtemperature protection that is intended Note 2: The LTC3129-1 is tested under pulsed load conditions such to protect the device during momentary overload conditions. Junction that TJ ≈ TA. The LTC3129E-1 is guaranteed to meet specifications temperature will exceed 125°C when overtemperature protection is active. from 0°C to 85°C junction temperature. Specifications over the –40°C Continuous operation above the specified maximum operating junction to 125°C operating junction temperature range are assured by design, temperature may result in device degradation or failure. characterization and correlation with statistical process controls. The Note 6: Failure to solder the exposed backside of the package to the PC LTC3129I-1 is guaranteed over the full –40°C to 125°C operating junction board ground plane will result in a much higher thermal resistance. temperature range. The junction temperature (TJ, in °C) is calculated from the ambient temperature (T Note 7: Switch timing measurements are made in an open-loop test A, in °C) and power dissipation (PD, in watts) according to the formula: configuration. Timing in the application may vary somewhat from these values due to differences in the switch pin voltage during non-overlap TJ = TA + (PD • θJA), durations when switch pin voltage is influenced by the magnitude and where θJA (in °C/W) is the package thermal impedance. duration of the inductor current. Note that the maximum ambient temperature consistent with these Note 8: Voltage transients on the switch pin(s) beyond the DC limits specifications is determined by specific operating conditions in specified in the Absolute Maximum Ratings are non-disruptive to normal conjunction with board layout, the rated thermal package thermal operation when using good layout practices as described elsewhere in the resistance and other environmental factors. data sheet and Application Notes and as seen on the product demo board. 31291fc 4 For more information www.linear.com/LTC3129-1