NCV303LSN44T1G

NCP302, NCP303 Voltage Detector Series with Programmable Delay The NCP302 and NCP303 series are second generation ultra−low current voltage detectors that contain a programmable time delay generator. These devices are specifically designed for use as reset controllers in portable microprocessor based systems where extended battery life is paramount. Each series features a highly accurate undervoltage detector with hysteresis and an externally programmable time delay generator. This combination of features prevents erratic system reset operation. The NCP302 series consists of complementary output devices that are available with either an active high or active low reset. The NCP303 series has an open drain N−Channel output with an active low reset output. Features http://onsemi.com MARKING DIAGRAM 5 5 1 TSOP−5/ SOT23−5 CASE 483 xxx AYWG G 1 • • • • • • • • • • • • Quiescent Current of 0.5 mA Typical High Accuracy Undervoltage Threshold of 2.0% Externally Programmable Time Delay Generator Wide Operating Voltage Range of 0.8 V to 10 V Complementary or Open Drain Output Active Low or Active High Reset Specified Over the −40°C to +125°C Temperature Range (Except for Voltage Options from 0.9 to 1.1 V) Pb−Free Packages are Available xxx A Y W G = Specific Device Code = Assembly Location = Year = Work Week = Pb−Free Package (Note: Microdot may be in either location) PIN CONNECTIONS Reset Output Input Ground 1 2 3 (Top View) 4 N.C. 5 CD Typical Applications Microprocessor Reset Controller Low Battery Detection Power Fail Indicator Battery Backup Detection ORDERING INFORMATION See detailed ordering and shipping information in the ordering information section on page 22 of this data sheet. NCP302xSNxxT1 Complementary Output Configuration 2 Input 2 NCP303LSNxxT1 Open Drain Output Configuration Input 1 Reset Output RD 1 RD Vref * 3 GND 5 CD Reset Output Vref 3 GND 5 CD * Inverter for active low devices. * Buffer for active high devices. This device contains 28 active transistors. Figure 1. Representative Block Diagrams © Semiconductor Components Industries, LLC, 2006 1 May, 2006 − Rev. 19 Publication Order Number: NCP302/D NCP302, NCP303 MAXIMUM RATINGS Rating Input Power Supply Voltage (Pin 2) Delay Capacitor Pin Voltage (Pin 5) Output Voltage (Pin 1) Complementary, NCP302 N−Channel Open Drain, NCP303 Output Current (Pin 1) (Note 2) Thermal Resistance Junction−to−Air Maximum Junction Temperature Operating Ambient Temperature Range All Voltage Options: 0.9 V to 1.1 V All Voltage Options: 1.2 V to 4.9 V Storage Temperature Range Moisture Sensitivity Level Latchup Performance (Note 3) Positive Negative All NCP Options All NCV Options Symbol Vin VCD VOUT −0.3 to Vin + 0.3 −0.3 to 12 IOUT RqJA TJ 70 250 +125 +150 −40 to +85 −40 to +125 −55 to +150 1 mA 200 200 mA °C/W °C Value 12 −0.3 to Vin + 0.3 Unit V V V TA TA Tstg MSL ILATCHUP °C °C °C Stresses exceeding Maximum Ratings may damage the device. Maximum Ratings are stress ratings only. Functional operation above the Recommended Operating Conditions is not implied. Extended exposure to stresses above the Recommended Operating Conditions may affect device reliability. 1. This device series contains ESD protection and exceeds the following tests: Human Body Model 2000 V per MIL−STD−883, Method 3015. Machine Model Method 200 V. 2. The maximum package power dissipation limit must not be exceeded. P D + T *T J(max) A R qJA 3. Maximum ratings per JEDEC standard JESD78. http://onsemi.com 2 NCP302, NCP303 ELECTRICAL CHARACTERISTICS (For all values TA = −40°C to +125°C, unless otherwise noted.) Characteristic NCP302/3 − 0.9 (TA = 255C for voltage options from 0.9 to 1.1 V) Detector Threshold (Pin 2, Vin Decreasing) Detector Threshold Hysteresis (Pin 2, Vin Increasing) Supply Current (Pin 2) (Vin = 0.8 V) (Vin = 2.9 V) Maximum Operating Voltage (Pin 2) Minimum Operating Voltage (Pin 2) (TA = −40°C to 85°C) Reset Output Current (Pin 1, Active Low ‘L’ Suffix Devices) Nch Sink Current, NCP302, NCP303 (VOUT = 0.05V, Vin = 0.70V) (VOUT = 0.50V, Vin = 0.85V) Pch Source Current, NCP302 (VOUT = 2.4V, Vin = 4.5V) Reset Output Current (Pin 1, Active High ‘H’ Suffix Devices) Nch Sink Current, NCP302, NCP303 (VOUT = 0.5 V, Vin = 1.5 V) Pch Source Current, NCP302 (VOUT = 0.4 V, Vin = 0.7 V) (VOUT = GND, Vin = 0.8 V) CD Delay Pin Threshold Voltage (Pin 5) (Vin = 0.99 V) Delay Capacitor Pin Sink Current (Pin 5) (Vin = 0.7 V, VCD = 0.1V) (Vin = 0.85 V, VCD = 0.5V) Delay Pullup Resistance (Pin 5) NCP302/3 − 1.8 Detector Threshold (Pin 2, Vin Decreasing) (TA = 25°C) (TA = −40°C to 125°C) Detector Threshold Hysteresis (Pin 2, Vin Increasing) Supply Current (Pin 2) (Vin = 1.7 V) (Vin = 3.8 V) Maximum Operating Voltage (Pin 2) Minimum Operating Voltage (Pin 2) (TA = 25°C) (TA = −40°C to 125°C) Reset Output Current (Pin 1, Active Low ‘L’ Suffix Devices) Nch Sink Current, NCP302, NCP303 (VOUT = 0.05V, Vin = 0.70V) (VOUT = 0.50V, Vin = 1.5V) Pch Source Current, NCP302 (VOUT = 2.4V, Vin = 4.5V) Reset Output Current (Pin 1, Active High ‘H’ Suffix Devices) Nch Sink Current, NCP302, NCP303 (VOUT = 0.5 V, Vin = 5.0 V) Pch Source Current, NCP302 (VOUT = 0.4 V, Vin = 0.7 V) (VOUT = GND, Vin = 1.5 V) CD Delay Pin Threshold Voltage (Pin 5) (Vin = 1.98 V) VTCD 0.99 1.34 1.68 IOUT 6.3 0.011 0.525 11 0.04 0.6 − − − V VDET− VHYS Iin − − Vin(max) Vin(min) IOUT 0.01 1.0 1.0 0.05 2.0 6.0 − − − mA − − − 0.23 0.48 − 0.55 0.65 0.7 1.3 10 0.70 0.80 V V mA 1.764 1.746 0.054 1.800 − 0.090 1.836 1.854 0.126 V V mA VTCD 0.50 ICD 2.0 10 RD 0.5 120 300 1.0 − − 2.0 MW 0.67 0.84 mA IOUT 1.05 0.011 0.014 2.5 0.04 0.08 − − − V VDET− VHYS Iin − − Vin(max) Vin(min) IOUT 0.01 0.05 1.0 0.05 0.50 6.0 − − − mA − − − 0.20 0.45 − 0.55 0.65 0.6 1.2 10 0.70 0.80 V V mA 0.882 0.027 0.900 0.045 0.918 0.063 V V mA Symbol Min Typ Max Unit http://onsemi.com 3 NCP302, NCP303 ELECTRICAL CHARACTERISTICS (continued) (For all values TA = −40°C to +125°C, unless otherwise noted.) Characteristic NCP302/3 − 1.8 Delay Capacitor Pin Sink Current (Pin 5) (Vin = 0.7 V, VCD = 0.1V) (Vin = 1.5 V, VCD = 0.5V) Delay Pullup Resistance (Pin 5) NCP302/3 − 2.0 Detector Threshold (Pin 2, Vin Decreasing) (TA = 25°C) (TA = −40°C to 125°C) Detector Threshold Hysteresis (Pin 2, Vin Increasing) Supply Current (Pin 2) (Vin = 1.9 V) (Vin = 4.0 V) Maximum Operating Voltage (Pin 2) Minimum Operating Voltage (Pin 2) (TA = 25°C) (TA = −40°C to 125°C) Reset Output Current (Pin 1, Active Low ‘L’ Suffix Devices) Nch Sink Current, NCP302, NCP303 (VOUT = 0.05V, Vin = 0.70V) (VOUT = 0.50V, Vin = 1.5V) Pch Source Current, NCP302 (VOUT = 2.4V, Vin = 4.5V) Reset Output Current (Pin 1, Active High ‘H’ Suffix Devices) Nch Sink Current, NCP302, NCP303 (VOUT = 0.5 V, Vin = 5.0 V) Pch Source Current, NCP302 (VOUT = 0.4 V, Vin = 0.7 V) (VOUT = GND, Vin = 1.5 V) CD Delay Pin Threshold Voltage (Pin 5) (Vin = 2.2 V) Delay Capacitor Pin Sink Current (Pin 5) (Vin = 0.7 V, VCD = 0.1V) (Vin = 1.5 V, VCD = 0.5V) Delay Pullup Resistance (Pin 5) NCP302/3− 2.7 Detector Threshold (Pin 2, Vin Decreasing) (TA = 25°C) (TA = −40°C to 125°C) Detector Threshold Hysteresis (Pin 2, Vin Increasing) Supply Current (Pin 2) (Vin = 2.6 V) (Vin = 4.7 V) Maximum Operating Voltage (Pin 2) Minimum Operating Voltage (Pin 2) (TA = 25°C) (TA = −40°C to 125°C) Reset Output Current (Pin 1, Active Low ‘L’ Suffix Devices) Nch Sink Current, NCP302, NCP303 (VOUT = 0.05V, Vin = 0.70V) (VOUT = 0.50V, Vin = 1.5V) Pch Source Current, NCP302 (VOUT = 2.4V, Vin = 4.5V) Reset Output Current (Pin 1, Active High ‘H’ Suffix Devices) Nch Sink Current, NCP302, NCP303 (VOUT = 0.5 V, Vin = 5.0 V) IOUT 6.3 11 − VDET− VHYS Iin − − Vin(max) Vin(min) IOUT 0.01 1.0 1.0 0.14 3.5 9.7 − − − mA − − − 0.25 0.50 − 0.55 0.65 0.8 1.3 10 0.70 0.80 V V mA 2.646 2.619 0.081 2.700 − 0.135 2.754 2.781 0.189 V V mA VTCD 1.10 ICD 2.0 200 RD 0.5 250 3600 1.0 − − 2.0 MW 1.49 1.87 mA IOUT 6.3 0.011 0.525 11 0.04 0.6 − − − V VDET− VHYS Iin − − Vin(max) Vin(min) IOUT 0.01 1.0 1.0 0.14 3.5 9.7 − − − mA − − − 0.23 0.48 − 0.55 0.65 0.8 1.3 10 0.70 0.80 V V mA 1.96 1.94 0.06 2.00 − 0.10 2.04 2.06 0.14 V V mA ICD 2.0 200 RD 0.5 120 1600 1.0 − − 2.0 MW mA Symbol Min Typ Max Unit http://onsemi.com 4 NCP302, NCP303 ELECTRICAL CHARACTERISTICS (continued) (For all values TA = −40°C to +125°C, unless otherwise noted.) Characteristic NCP302/3− 2.7 Pch Source Current, NCP302 (VOUT = 0.4 V, Vin = 0.7 V) (VOUT = GND, Vin = 1.5 V) CD Delay Pin Threshold Voltage (Pin 5) (Vin = 2.97 V) Delay Capacitor Pin Sink Current (Pin 5) (Vin = 0.7 V, VCD = 0.1V) (Vin = 1.5 V, VCD = 0.5V) Delay Pullup Resistance (Pin 5) NCP302/3 − 3.0 Detector Threshold (Pin 2, Vin Decreasing) (TA = 25°C) (TA = −40°C to 125°C) Detector Threshold Hysteresis (Pin 2, Vin Increasing) Supply Current (Pin 2) (Vin = 2.87 V) (Vin = 5.0 V) Maximum Operating Voltage (Pin 2) Minimum Operating Voltage (Pin 2) (TA = 25°C) (TA = −40°C to 125°C) Reset Output Current (Pin 1, Active Low ‘L’ Suffix Devices) Nch Sink Current, NCP302, NCP303 (VOUT = 0.05V, Vin = 0.70V) (VOUT = 0.50V, Vin = 1.5V) Pch Source Current, NCP302 (VOUT = 2.4V, Vin = 4.5V) Reset Output Current (Pin 1, Active High ‘H’ Suffix Devices) Nch Sink Current, NCP302, NCP303 (VOUT = 0.5 V, Vin = 5.0 V) Pch Source Current, NCP302 (VOUT = 0.4 V, Vin = 0.7 V) (VOUT = GND, Vin = 1.5 V) CD Delay Pin Threshold Voltage (Pin 5) (Vin = 3.3 V) Delay Capacitor Pin Sink Current (Pin 5) (Vin = 0.7 V, VCD = 0.1V) (Vin = 1.5 V, VCD = 0.5V) Delay Pullup Resistance (Pin 5) NCP302/3 − 4.5 Detector Threshold (Pin 2, Vin Decreasing) (TA = 25°C) (TA = −40°C to 125°C) Detector Threshold Hysteresis (Pin 2, Vin Increasing) Supply Current (Pin 2) (Vin = 4.34 V) (Vin = 6.5 V) Maximum Operating Voltage (Pin 2) Minimum Operating Voltage (Pin 2) (TA = 25°C) (TA = −40°C to 125°C) Reset Output Current (Pin 1, Active Low ‘L’ Suffix Devices) Nch Sink Current, NCP302, NCP303 (VOUT = 0.05V, Vin = 0.70V) (VOUT = 0.50V, Vin = 1.5V) VDET− VHYS Iin − − Vin(max) Vin(min) IOUT 0.01 1.0 0.05 2.0 − − − − − 0.33 0.52 − 0.55 0.65 1.0 1.4 10 0.70 0.80 V V mA 4.410 4.365 0.135 4.500 − 0.225 4.590 4.635 0.315 V V mA VTCD 1.65 ICD 2.0 200 RD 0.5 250 3600 1.0 − − 2.0 MW 2.23 2.81 mA IOUT 6.3 0.011 0.525 11 0.04 0.6 − − − V VDET− VHYS Iin − − Vin(max) Vin(min) IOUT 0.01 1.0 1.0 0.14 3.5 9.7 − − − mA − − − 0.25 0.50 − 0.55 0.65 0.9 1.3 10 0.70 0.80 V V mA 2.94 2.91 0.09 3.00 − 0.15 3.06 3.09 0.21 V V mA VTCD 1.49 ICD 2.0 200 RD 0.5 250 3600 1.0 − − 2.0 MW 2.01 2.53 mA 0.011 0.525 0.04 0.6 − − V Symbol Min Typ Max Unit http://onsemi.com 5 NCP302, NCP303 ELECTRICAL CHARACTERISTICS (continued) (For all values TA = −40°C to +125°C, unless otherwise noted.) Characteristic NCP302/3 − 4.5 Pch Source Current, NCP302 (VOUT = 5.9V, Vin = 8.0V) Reset Output Current (Pin 1, Active High ‘H’ Suffix Devices) Nch Sink Current, NCP302, NCP303 (VOUT = 0.5 V, Vin = 5.0 V) Pch Source Current, NCP302 (VOUT = 0.4 V, Vin = 0.7 V) (VOUT = GND, Vin = 1.5 V) CD Delay Pin Threshold Voltage (Pin 5) (Vin = 4.95 V) Delay Capacitor Pin Sink Current (Pin 5) (Vin = 0.7 V, VCD = 0.1V) (Vin = 1.5 V, VCD = 0.5V) Delay Pullup Resistance (Pin 5) NCP302/3 − 4.7 Detector Threshold (Pin 2, Vin Decreasing) (TA = 25°C) (TA = −40°C to 125°C) Detector Threshold Hysteresis (Pin 2, Vin Increasing) Supply Current (Pin 2) (Vin = 4.54 V) (Vin = 6.7 V) Maximum Operating Voltage (Pin 2) Minimum Operating Voltage (Pin 2) (TA = 25°C) (TA = −40°C to 125°C) Reset Output Current (Pin 1, Active Low ‘L’ Suffix Devices) Nch Sink Current, NCP302, NCP303 (VOUT = 0.05V, Vin = 0.70V) (VOUT = 0.50V, Vin = 1.5V) Pch Source Current, NCP302 (VOUT = 5.9V, Vin = 8.0V) Reset Output Current (Pin 1, Active High ‘H’ Suffix Devices) Nch Sink Current, NCP302, NCP303 (VOUT = 0.5 V, Vin = 5.0 V) Pch Source Current, NCP302 (VOUT = 0.4 V, Vin = 0.7 V) (VOUT = GND, Vin = 1.5 V) CD Delay Pin Threshold Voltage (Pin 5) (Vin = 5.17 V) Delay Capacitor Pin Sink Current (Pin 5) (Vin = 0.7 V, VCD = 0.1V) (Vin = 1.5 V, VCD = 0.5V) Delay Pullup Resistance (Pin 5) VTCD 2.59 ICD 2.0 200 RD 0.5 120 1600 1.0 − − 2.0 MW 3.49 4.40 mA IOUT 6.3 0.011 0.525 11 0.04 0.6 − − − V VDET− VHYS Iin − − Vin(max) Vin(min) IOUT 0.01 1.0 1.5 0.05 2.0 10.5 − − − mA − − − 0.34 0.53 − 0.55 0.65 1.0 1.4 10 0.70 0.80 V V mA 4.606 4.559 0.141 4.700 − 0.235 4.794 4.841 0.329 V V mA VTCD 2.25 ICD 2.0 200 RD 0.5 120 1600 1.0 − − 2.0 MW 3.04 3.83 mA IOUT 6.3 0.011 0.525 11 0.04 0.6 − − − V 1.5 10.5 − mA Symbol Min Typ Max Unit http://onsemi.com 6 NCP302, NCP303 NCP302L VDET+ + 2.0 V VDET+ + 2.0 V NCP303L Input Voltage, Pin 2 0.7 V GND VDET+ + 2.0 V 0.7 V GND 5.0 V Reset Output Voltage, Pin 1 VDET+ + 2.0 V 2 2.5 V GND tD1 tD2 GND tD1 tD2 NCP302 and NCP303 series are measured with a 10 pF capacitive load. NCP303 has an additional 470 k pullup resistor connected from the reset output to +5.0 V. The reset output voltage waveforms are shown for the active low ‘L’ devices. Output time delay tD1 and tD2 are dependent upon the delay capacitance. Refer to Figures 30, 31, and 32. The upper detector threshold, VDET+ is the sum of the lower detector threshold, VDET− plus the input hysteresis, VHYS. Figure 2. Measurement Conditions for tD1 and tD2 http://onsemi.com 7 NCP302, NCP303 Table 1. ELECTRICAL CHARACTERISTIC TABLE FOR 0.9 − 4.9 V Supply Current NCP302 Series Detector Threshold VDET− (V) (Note 4) Part Number NCP302LSN09T1 NCP302LSN15T1 NCP302LSN18T1 NCP302LSN20T1 NCP302LSN27T1 NCP302LSN30T1 NCP302LSN33T1 NCP302LSN38T1 NCP302LSN40T1 NCP302LSN43T1 NCP302LSN45T1 NCP302LSN47T1 Min 0.882 1.470 1.764 1.960 2.646 2.940 3.234 3.724 3.920 4.214 4.410 4.606 Typ 0.9 1.5 1.8 2.0 2.7 3.0 3.3 3.8 4.0 4.3 4.5 4.7 Max 0.918 1.530 1.836 2.040 2.754 3.060 3.366 3.876 4.080 4.386 4.590 4.794 Min 0.027 0.045 0.054 0.060 0.081 0.090 0.099 0.114 0.120 0.129 0.135 0.141 Detector Threshold Hysteresis VHYS (V) Typ 0.045 0.075 0.090 0.100 0.135 0.150 0.165 0.190 0.200 0.215 0.225 0.235 Max 0.063 0.105 0.126 0.140 0.189 0.210 0.231 0.266 0.280 0.301 0.315 0.329 0.33 0.34 0.52 0.53 3.0 0.25 0.50 0.23 0.48 Vin Low Iin (mA) (Note 5) Typ 0.20 Vin High Iin (mA) (Note 6) Typ 0.45 Nch Sink Current Vin Low IOUT (mA) (Note 7) Typ 0.05 Vin High IOUT (mA) (Note 8) Typ 0.5 Pch Source Current IOUT(mA) (Note 9) Typ 2.0 4. Values shown apply at +25°C only. For voltage options greater than 1.1 V, VDET− limits over operating temperature range (−40°C to +125°C) are VNOM ±3%. For voltage options < 1.2 V, VDET− is guaranteed only at +25°C. 5. Condition 1: 0.9 — 2.9 V, Vin = VDET− − 0.10 V; 3.0 — 3.9 V, Vin = VDET− − 0.13 V; 4.0 — 4.9 V, Vin = VDET− − 0.16 V 6. Condition 2: 0.9 — 4.9 V, Vin = VDET− + 2.0 V 7. Condition 3: 0.9 — 4.9 V, Vin = 0.7 V, VOUT = 0.05 V, Active Low ‘L’ Suffix Devices 8. Condition 4: 0.9 — 1.0 V, Vin = 0.85 V, VOUT = 0.5 V; 1.1 — 1.5 V, Vin = 1.0 V, VOUT = 0.5 V; 1.6 — 4.9 V, Vin = 1.5 V, VOUT = 0.5 V, Condition 4: Active Low ‘L’ Suffix Devices 9. Condition 5: 0.9 — 3.9 V, Vin = 4.5 V, VOUT = 2.4 V; 4.0 — 4.9 V, Vin = 8.0 V, VOUT = 5.9 V, Active Low ‘L’ Suffix Devices Table 2. ELECTRICAL CHARACTERISTIC TABLE FOR 0.9 − 4.9 V Detector Threshold Hysteresis VHYS (V) Min 0.027 0.054 0.081 0.090 0.120 0.135 Typ 0.045 0.090 0.135 0.150 0.200 0.225 Max 0.063 0.126 0.189 0.210 0.280 0.315 0.33 0.52 Supply Current Vin Low Iin (mA) (Note 11) Typ 0.20 0.23 0.25 Vin High Iin (mA) (Note 12) Typ 0.45 0.48 0.50 Nch Sink Current IOUT (mA) (Note 13) Typ 2.5 Pch Source Current Vin Low IOUT (mA) (Note 14) Typ 0.04 Vin High IOUT (mA) (Note 15) Typ 0.08 NCP302 Series Detector Threshold VDET− (V) (Note 10) Part Number NCP302HSN09T1 NCP302HSN18T1 NCP302HSN27T1 NCP302HSN30T1 NCP302HSN40T1 NCP302HSN45T1 Min 0.882 1.764 2.646 2.940 3.920 4.410 Typ 0.9 1.8 2.7 3.0 4.0 4.5 Max 0.918 1.836 2.754 3.060 4.080 4.590 10. Values shown apply at +25°C only. For voltage options greater than 1.1 V, VDET− limits over operating temperature range (−40°C to +125°C) are VNOM ±3%. For voltage options < 1.2 V, VDET− is guaranteed only at +25°C. 11. Condition 1: 0.9 — 2.9 V, Vin = VDET− − 0.10 V; 3.0 — 3.9 V, Vin = VDET− − 0.13 V; 4.0 — 4.9 V, Vin = VDET− − 0.16 V 12. Condition 2: 0.9 — 4.9 V, Vin = VDET− + 2.0 V 13. Condition 3: 0.9 — 1.4 V, Vin = 1.5 V, VOUT = 0.5 V; 1.5 — 4.9 V, Vin = 5.0 V, VOUT = 0.5 V, Active High ‘H’ Suffix Devices 14. Condition 4: 0.9 — 4.9 V, Vin = 0.7 V, VOUT = 0.4 V, Active High ‘H’ Suffix Devices 15. Condition 5: 0.9 — 1.0 V, Vin = 0.8 V, VOUT = GND; 1.1 — 1.5 V, Vin = 1.0 V, VOUT = GND; 1.6 — 4.9 V, Vin = 1.5 V, VOUT = GND, Active High ‘H’ Suffix Devices http://onsemi.com 8 NCP302, NCP303 Table 3. ELECTRICAL CHARACTERISTIC TABLE FOR 0.9 − 4.9 V Detector Threshold Hysteresis VHYS (V) Min 0.027 0.030 0.033 0.039 0.042 0.045 0.048 0.051 0.054 0.060 0.066 0.069 0.072 0.075 0.078 0.081 0.084 0.087 0.090 0.093 0.096 0.099 0.102 0.108 0.114 0.120 0.126 0.132 0.135 0.138 0.141 0.147 Typ 0.045 0.050 0.055 0.065 0.070 0.075 0.080 0.085 0.090 0.100 0.110 0.115 0.120 0.125 0.130 0.135 0.140 0.145 0.150 0.155 0.160 0.165 0.170 0.180 0.190 0.200 0.210 0.220 0.225 0.230 0.235 0.245 Max 0.063 0.070 0.077 0.091 0.098 0.105 0.112 0.119 0.126 0.140 0.154 0.161 0.168 0.175 0.182 0.189 0.196 0.203 0.210 0.217 0.224 0.231 0.238 0.252 0.266 0.280 0.294 0.308 0.315 0.322 0.329 0.343 0.34 0.53 0.33 0.52 0.25 0.50 0.23 0.48 2.0 1.0 Supply Current Vin Low Iin (mA) (Note 17) Typ 0.20 Vin High Iin (mA) (Note 18) Typ 0.45 Nch Sink Current Vin Low IOUT (mA) (Note 19) Typ 0.05 Vin High IOUT (mA) (Note 20) Typ 0.5 NCP303 Series Detector Threshold VDET− (V) (Note 16) Part Number NCP303LSN09T1 NCP303LSN10T1 NCP303LSN11T1 NCP303LSN13T1 NCP303LSN14T1 NCP303LSN15T1 NCP303LSN16T1 NCP303LSN17T1 NCP303LSN18T1 NCP303LSN20T1 NCP303LSN22T1 NCP303LSN23T1 NCP303LSN24T1 NCP303LSN25T1 NCP303LSN26T1 NCP303LSN27T1 NCP303LSN28T1 NCP303LSN29T1 NCP303LSN30T1 NCP303LSN31T1 NCP303LSN32T1 NCP303LSN33T1 NCP303LSN34T1 NCP303LSN36T1 NCP303LSN38T1 NCP303LSN40T1 NCP303LSN42T1 NCP303LSN44T1 NCP303LSN45T1 NCP303LSN46T1 NCP303LSN47T1 NCP303LSN49T1 Min 0.882 0.980 1.078 1.274 1.372 1.470 1.568 1.666 1.764 1.960 2.156 2.254 2.352 2.450 2.548 2.646 2.744 2.842 2.940 3.038 3.136 3.234 3.332 3.528 3.724 3.920 4.116 4.312 4.410 4.508 4.606 4.802 Typ 0.9 1.0 1.1 1.3 1.4 1.5 1.6 1.7 1.8 2.0 2.2 2.3 2.4 2.5 2.6 2.7 2.8 2.9 3.0 3.1 3.2 3.3 3.4 3.6 3.8 4.0 4.2 4.4 4.5 4.6 4.7 4.9 Max 0.918 1.020 1.122 1.326 1.428 1.530 1.632 1.734 1.836 2.040 2.244 2.346 2.448 2.550 2.652 2.754 2.856 2.958 3.060 3.162 3.264 3.366 3.468 3.672 3.876 4.080 4.284 4.488 4.590 4.692 4.794 4.998 16. Values shown apply at +25°C only. For voltage options greater than 1.1 V, VDET− limits over operating temperature range (−40°C to +125°C) are VNOM ±3%. For voltage options < 1.2 V, VDET− is guaranteed only at +25°C. 17. Condition 1: 0.9 — 2.9 V, Vin = VDET− − 0.10 V; 3.0 — 3.9 V, Vin = VDET− − 0.13 V; 4.0 — 4.9 V, Vin = VDET− − 0.16 V 18. Condition 2: 0.9 — 4.9 V, Vin = VDET− + 2.0 V 19. Condition 3: 0.9 — 4.9 V, Vin = 0.7 V, VOUT = 0.05 V, Active Low ‘L’ Suffix Devices 20. Condition 4: 0.9 — 1.0 V, Vin = 0.85 V, VOUT = 0.5 V; 1.1 — 1.5 V, Vin = 1.0 V, VOUT = 0.5 V; 1.6 — 4.9 V, Vin = 1.5 V, VOUT = 0.5 V, Condition 4: Active Low ‘L’ Suffix Devices http://onsemi.com 9 NCP302, NCP303 1.0 0.9 Iin, INPUT CURRENT (mA) 0.8 0.7 0.6 0.5 0.4 0.3 0.2 0.1 0 0 2.0 4.0 6.0 8.0 10 12 Vin, INPUT VOLTAGE (V) 0 0 2.0 4.0 6.0 8.0 Vin, INPUT VOLTAGE (V) 10 12 TA = 25°C Iin, INPUT CURRENT (mA) 2.5 2.0 1.5 1.0 0.5 10.5 TA = 25°C Figure 3. NCP302/3 Series 0.9 V Input Current vs. Input Voltage VDET, DETECTOR THRESHOLD VOLTAGE (V) 17.2 TA = 25°C Iin, INPUT CURRENT (mA) 2.5 2.0 1.5 1.0 0.5 0 0 2.0 4.0 6.0 8.0 10 12 Vin, INPUT VOLTAGE (V) 1.00 Figure 4. NCP302/3 Series 2.7 V Input Current vs. Input Voltage 0.95 VDET+ 0.90 VDET− 0.85 0.80 −50 −25 0 25 50 75 100 TA, AMBIENT TEMPERATURE (°C) Figure 5. NCP302/3 Series 4.5 V Input Current vs. Input Voltage VDET, DETECTOR THRESHOLD VOLTAGE (V) Figure 6. NCP302/3 Series 0.9 V Detector Threshold Voltage vs. Temperature 2.90 2.85 2.80 2.75 2.70 2.65 2.60 −50 VDET− VDET+ VDET, DETECTOR THRESHOLD VOLTAGE (V) 4.9 4.8 VDET+ 4.7 4.6 4.5 4.4 4.3 −50 VDET− −25 0 25 50 75 100 125 −25 0 25 50 75 100 125 TA, AMBIENT TEMPERATURE (°C) TA, AMBIENT TEMPERATURE (°C) Figure 7. NCP302/3 Series 2.7 V Detector Threshold Voltage vs. Temperature Figure 8. NCP302/3 Series 4.5 V Detector Threshold Voltage vs. Temperature http://onsemi.com 10 NCP302, NCP303 1.0 VOUT, OUTPUT VOLTAGE (V) VOUT, OUTPUT VOLTAGE (V) 3.5 3.0 2.5 2.0 1.5 1.0 0.5 0 0 0.2 0.4 0.6 Vin, INPUT VOLTAGE (V) 0.8 1.0 0 0.5 1.5 2.5 1.0 2.0 Vin, INPUT VOLTAGE (V) 3.0 3.5 TA = 125°C (303L only) TA = −40°C (303L only) TA = 25°C (303L only) 0.8 0.6 TA = −40°C (303L only) TA = 25°C (303L only) 0.4 0.2 0 Figure 9. NCP302L/3L Series 0.9 V Reset Output Voltage vs. Input Voltage 6.0 IOUT, OUTPUT SINK CURRENT (mA) VOUT, OUTPUT VOLTAGE (V) 5.0 4.0 3.0 2.0 1.0 0 0 1.0 2.0 4.0 3.0 Vin, INPUT VOLTAGE (V) 5.0 6.0 TA = −40°C (303L only) TA = 25°C (303L only) 1.6 1.4 1.2 1.0 0.8 0.6 0.4 0.2 0 0 Figure 10. NCP302L/3L Series 2.7 V Reset Output Voltage vs. Input Voltage VOUT = 0.5 V TA = −40°C TA = 25°C TA = 85°C 0.2 0.4 0.6 0.8 1.0 Vin, INPUT VOLTAGE (V) Figure 11. NCP302L/3L Series 4.5 V Reset Output Voltage vs. Input Voltage 12 IOUT, OUTPUT SINK CURRENT (mA) IOUT, OUTPUT SINK CURRENT (mA) VOUT = 0.5 V 10 8.0 6.0 4.0 2.0 0 0 0.5 1.0 1.5 2.0 2.5 3.0 Vin, INPUT VOLTAGE (V) TA = 25°C TA = 125°C TA = −40°C 20 Figure 12. NCP302H/3L Series 0.9 V Reset Output Sink Current vs. Input Voltage VOUT = 0.5 V TA = −40°C 15 10 TA = 25°C 5.0 TA = 125°C 0 0 1.0 2.0 3.0 4.0 5.0 Vin, INPUT VOLTAGE (V) Figure 13. NCP302H/3L Series 2.7 V Reset Output Sink Current vs. Input Voltage Figure 14. NCP302H/3L Series 4.5 V Reset Output Sink Current vs. Input Voltage http://onsemi.com 11 NCP302, NCP303 IOUT, OUTPUT SOURCE CURRENT (mA) 20 TA = 25°C 15 IOUT, OUTPUT SOURCE CURRENT (mA) VOUT = Vin −2.1 V 20 TA = 25°C 15 VOUT = Vin −2.1 V Vin −1.5 V 10 Vin −1.5 V Vin −1.0 V 10 Vin −1.0 V 5.0 Vin −0.5 V 0 0 2.0 4.0 6.0 8.0 10 Vin, INPUT VOLTAGE (V) 5.0 Vin −0.5 V 0 0 2.0 4.0 6.0 8.0 10 Vin, INPUT VOLTAGE (V) Figure 15. NCP302L Series 0.9 V Reset Output Source Current vs. Input Voltage Figure 16. NCP302L Series 2.7 V Reset Output Source Current vs. Input Voltage IOUT, OUTPUT SOURCE CURRENT (mA) 20 VOUT = Vin −2.1 V IOUT, OUTPUT SINK CURRENT (mA) TA = 25°C 1.5 TA = 25°C 15 1.0 Vin = 0.85 V 10 Vin −1.5 V Vin −1.0 V 0.5 Vin = 0.7 V 5.0 Vin −0.5 V 0 0 2.0 4.0 6.0 8.0 10 Vin, INPUT VOLTAGE (V) 0 0 0.2 0.4 0.6 0.8 1.0 VOUT, OUTPUT VOLTAGE (V) Figure 17. NCP302L Series 4.5 V Reset Output Source Current vs. Input Voltage Figure 18. NCP302H/3L Series 0.9 V Reset Output Sink Current vs. Output Voltage 15 IOUT, OUTPUT SINK CURRENT (mA) Vin = 2.5 V IOUT, OUTPUT SINK CURRENT (mA) TA = 25°C 35 TA = 25°C 30 25 Vin = 3.5 V 20 15 10 5.0 0 0 0.5 1.0 1.5 2.0 2.5 0 1.0 2.0 3.0 4.0 VOUT, OUTPUT VOLTAGE (V) VOUT, OUTPUT VOLTAGE (V) Vin = 3.0 V Vin = 2.5 V Vin = 2.0 V Vin = 1.5 V Vin = 4.0 V 10 Vin = 2.0 V 5.0 Vin = 1.5 V 0 Figure 19. NCP302H/3L Series 2.7 V Reset Output Sink Current vs. Output Voltage Figure 20. NCP302H/3L Series 4.5 V Reset Output Sink Current vs. Output Voltage http://onsemi.com 12 NCP302, NCP303 ICD, CD DELAY PIN SINK CURRENT (mA) ICD, CD DELAY PIN SINK CURRENT (mA) 1.6 1.4 1.2 1.0 0.8 0.6 0.4 0.2 0 0 0.2 0.4 0.6 0.8 1.0 Vin, INPUT VOLTAGE (V) TA = 85°C TA = −40°C TA = 25°C VCD = 0.5 V 14 VCD = 0.5 V 12 10 8.0 6.0 4.0 2.0 0 0 0.5 1.0 1.5 2.0 2.5 3.0 Vin, INPUT VOLTAGE (V) TA = 25°C TA = 125°C TA = −40°C Figure 21. NCP302/3 Series 0.9 V CD Delay Pin Sink Current vs. Input Voltage ICD, CD DELAY PIN SINK CURRENT (mA) ICD, CD DELAY PIN SINK CURRENT (mA) 20 VCD = 0.5 V 16 TA = −40°C 1.5 Figure 22. NCP302/3 Series 2.7 V CD Delay Pin Sink Current vs. Input Voltage TA = 25°C 1.0 Vin = 0.85 V 12 TA = 25°C 8.0 TA = 125°C 4.0 0.5 Vin = 0.7 V 0 0 1.0 2.0 3.0 4.0 5.0 Vin, INPUT VOLTAGE (V) 0 0 0.2 0.4 0.6 0.8 1.0 VCD, DELAY PIN VOLTAGE (V) Figure 23. NCP302/3 Series 4.5 V CD Delay Pin Sink Current vs. Input Voltage Figure 24. NCP302/3 Series 0.9 V CD Delay Pin Sink Current vs. Voltage ICD, CD DELAY PIN SINK CURRENT (mA) ICD, CD DELAY PIN SINK CURRENT (mA) 16 40 TA = 25°C 30 Vin = 4.0 V Vin = 3.5 V 20 Vin = 3.0 V Vin = 2.5 V 10 TA = 25°C Vin = 2.5 V 12 8.0 Vin = 2.0 V 4.0 Vin = 1.5 V 0 0 0.5 1.0 1.5 2.0 2.5 VCD, DELAY PIN VOLTAGE (V) 0 0 1.0 2.0 3.0 4.0 VCD, DELAY PIN VOLTAGE (V) Figure 25. NCP302/3 Series 2.7 V CD Delay Pin Sink Current vs. Voltage http://onsemi.com 13 Figure 26. NCP302/3 Series 4.5 V CD Delay Pin Sink Current vs. Voltage NCP302, NCP303 VTCD, CD PIN THRESHOLD VOLTAGE (V) Vin = 0.99 V 0.8 0.7 0.6 0.5 0.4 0.3 −50 VTCD, CD PIN THRESHOLD VOLTAGE (V) 0.9 2.2 Vin = 2.97 V 2.1 2.0 1.9 1.8 −25 0 75 25 50 TA, AMBIENT TEMPERATURE (°C) 100 1.7 −50 −25 0 75 100 25 50 TA, AMBIENT TEMPERATURE (°C) 125 Figure 27. NCP302/3 Series 0.9 V CD Delay Pin Threshold Voltage vs. Temperature Figure 28. NCP302/3 Series 2.7 V CD Delay Pin Threshold Voltage vs. Temperature VTCD, CD PIN THRESHOLD VOLTAGE (V) 3.7 Vin = 4.95 V 3.6 10000 TA = 25°C t D1, t D2 , OUTPUT TIME DELAY 1000 tD1 (ms) 100 tD2 (ms) 3.5 3.4 10 3.3 1.0 0.1 0.00001 3.2 −50 −25 0 25 50 75 100 125 0.0001 0.001 0.01 0.1 1.0 TA, AMBIENT TEMPERATURE (°C) CD, DELAY PIN CAPACITANCE ( mF) Figure 29. NCP302/3 Series 4.5 V CD Delay Pin Threshold Voltage vs. Temperature Figure 30. NCP302/3 Series 0.9 V Output Time Delay vs. Capacitance 10000 TA = 25°C t D1, t D2 , OUTPUT TIME DELAY 1000 tD1 (ms) 10000 TA = 25°C t D1, t D2 , OUTPUT TIME DELAY 1000 tD1 (ms) 100 100 10 tD2 (ms) 10 tD2 (ms) 1.0 0.1 0.00001 1.0 0.1 0.00001 0.0001 0.001 0.01 0.1 1.0 0.0001 0.001 0.01 0.1 1.0 CD, DELAY PIN CAPACITANCE ( mF) CD, DELAY PIN CAPACITANCE ( mF) Figure 31. NCP302/3 Series 2.7 V Output Time Delay vs. Capacitance Figure 32. NCP302/3 Series 4.5 V Output Time Delay vs. Capacitance http://onsemi.com 14 NCP302, NCP303 250 CD = 0.1 mF tD2, OUTPUT TIME DELAY (ms) 200 160 120 80 40 0 −50 tD2, OUTPUT TIME DELAY (ms) 160 140 120 100 80 60 40 20 0 −50 −25 0 25 50 75 100 125 CD = 0.1 mF −25 0 25 50 75 100 TA, AMBIENT TEMPERATURE (°C) TA, AMBIENT TEMPERATURE (°C) Figure 33. NCP302/3 Series 0.9 V Reset Output Time Delay vs. Temperature 250 tD2, OUTPUT TIME DELAY (ms) CD = 0.1 mF RD, DELAY RESISTANCE (MW) 1.6 Figure 34. NCP302/3 Series 2.7 V Reset Output Time Delay vs. Temperature 200 1.2 150 0.8 100 0.4 50 0 −50 −25 0 25 50 75 100 0 −50 −25 0 25 50 75 100 125 TA, AMBIENT TEMPERATURE (°C) TA, AMBIENT TEMPERATURE (°C) Figure 35. NCP302/3 Series 4.5 V Reset Output Time Delay vs. Temperature Figure 36. NCP302/3 Series Delay Resistance vs. Temperature http://onsemi.com 15 NCP302, NCP303 OPERATING DESCRIPTION The NCP302 and NCP303 series devices consist of a precision voltage detector that drives a time delay generator. Figures 37 and 38 show a timing diagram and a typical application. Initially consider that input voltage Vin is at a nominal level and it is greater than the voltage detector upper threshold (VDET+). The voltage at Pin 5 and capacitor CD will be at the same level as Vin, and the reset output (Pin 1) will be in the high state for active low devices, or in the low state for active high devices. If there is a power interruption and Vin becomes significantly deficient, it will fall below the lower detector threshold (VDET−) and the external time delay capacitor CD will be immediately discharged by an internal N−Channel MOSFET that connects to Pin 5. This sequence of events causes the Reset output to be in the low state for active low devices, or in the high state for active high devices. After completion of the power interruption, Vin will again return to its nominal level and become greater than the VDET+. The voltage detector will turn off the N−Channel MOSFET and allow pullup resistor RD to charge external capacitor CD, thus creating a programmable delay for releasing the reset signal. When the voltage at Pin 5 exceeds the inverter/buffer threshold, typically 0.675 Vin, the reset output will revert back to its original state. The reset output time delay versus capacitance is shown in Figures 12 through 14. The voltage detector and inverter/buffer have built−in hysteresis to prevent erratic reset operation. Although these device series are specifically designed for use as reset controllers in portable microprocessor based systems, they offer a cost−effective solution in numerous applications where precise voltage monitoring and time delay are required. Figures 38 through 45 show various application examples. Input Voltage, Pin 2 Vin VDET+ VDET− Vin Capacitor, Pin 5 0.675 Vin Reset Output (Active Low), Pin 1 Vin VDET− 0V Reset Output (Active High), Pin 1 Vin VDET− 0V tD2 Figure 37. Timing Waveforms http://onsemi.com 16 NCP302, NCP303 APPLICATION CIRCUIT INFORMATION VDD VDD 2 5 CD CD Input 1 Reset Output * Reset NCP302 Series Microprocessor 3 GND * Required for NCP303 GND Figure 38. Microprocessor Reset Circuit 2.85 V 2.70 V 2 5 CD Input 1 Vin < 2.7 ON NCP302 LSN27T1 To Additional Circuitry Reset Output Vin > 2.835 ON 3 GND Figure 39. Battery Charge Indicator 5.0 V 1.0 V 0V 2 5 CD CD Input 1 Vsupply 470 k NCP303 LSN45T1 3 GND To Additional Circuitry Reset Output 0.001 mF Missing Pulse Input 0V Vin [0.675*Vin CD Reset Output tD2 Figure 40. Missing Pulse Detector or Frequency Detector http://onsemi.com 17 NCP302, NCP303 VDD RH 2 5 CD Input RL NCP303 NCP301 LSN27T1 3 GND 1 Microprocessor Reset Output Reset GND VDD Figure 41. Microprocessor Reset Circuit with Additional Hysteresis Vin Decreasing: V th + RH )1 R in V DET* Vin Increasing: V th + RH )1 R in ø R L V DET* ) V HYS VHYS = Vin Increasing − Vin Decreasing 5.0 V 100 k Test Data C C (mF) 2 5 CD Input 82 k NCP302 NCP301 HSN27T1 LSN27T1 3 GND 1 Reset Output 0.01 0.1 1.0 2590 490 52 21.77 21.97 22.07 fOSC (kHz) IQ (mA) Figure 42. Simple Clock Oscillator http://onsemi.com 18 ÁÁ Á Á ÁÁÁ Á Á Á ÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁ ÁÁÁ Á ÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁ ÁÁÁ Á ÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁ ÁÁÁ Á ÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁ ÁÁÁ Á ÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁ ÁÁÁ Á ÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁ ÁÁÁÁÁÁÁÁÁÁÁÁÁÁ Á ÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁ ÁÁÁ 2.70 2.70 2.70 2.70 2.70 2.70 2.70 2.70 2.70 2.70 2.84 2.87 2.88 2.91 2.90 2.94 2.98 2.70 3.04 3.15 0.135 0.17 0.19 0.21 0.20 0.24 0.28 0.27 0.34 0.35 0 100 100 100 220 220 220 470 470 470 − 10 6.8 4.3 10 6.8 4.3 10 6.8 4.3 Comparator hysteresis can be increased with the addition of resistor RH. The hysteresis equations have been simplified and do not account for the change of input current Iin as Vin crosses the comparator threshold. The internal resistance, Rin is simply calculated using Iin = 0.26 mA at 2.6 V. Test Data Vth Decreasing (V) Vth Increasing (V) VHYS (V) RH (W) RL (kW) NCP302, NCP303 Vsupply This circuit monitors the current at the load. As current flows through the load, a voltage drop with respect to ground appears across Rsense where Vsense = Iload * Rsense. The following conditions apply: If: ILoad t VDET − /Rsense ILoad w (VDET −+VHYS)/Rsense Microcontroller Then: Reset Output = 0 V Reset Output = VDD Load VDD Rsense 5 CD 2 Input 50 k 1 Reset Output GND NCP303 NCP301 LSN09T1 LSN27T1 3 GND Figure 43. Microcontroller Systems Load Sensing Vsupply 2 5 CD Input 1 Reset Output NCP303 NCP301 LSN45T1 LSN27T1 3 GND 2 5 CD Input 1 Reset Output NCP303 NCP301 LSN27T1 3 GND Vin = 1.0 V to 10 V 2 5 CD Input 1 Reset Output NCP303 NCP301 LSN18T1 LSN27T1 3 GND A simple voltage monitor can be constructed by connecting several voltage detectors as shown above. Each LED will sequentially turn on when the respective voltage detector threshold (VDET− +VHYS) is exceeded. Note that detector thresholds (VDET−) that range from 0.9 V to 4.9 V in 100 mV steps can be manufactured. Figure 44. LED Bar Graph Voltage Monitor http://onsemi.com 19 NCP302, NCP303 VDD 2 EN 5 IN Logic 1 CD 3 GND CD NCP302L Series 1 Reset Output To MCU or Logic Circuitry Input VDD NCP302 Input Pin VDET 0V Logic 1 Enable Pin 1 0 VDD VTCD 0V Reset Output 0V Note: Logic 1 is in tristate when EN = 0, VTCD  0.675 * VDD tD2 tD2 CD Pin Figure 45. Undervoltage Detection with Independent Reset Signal Control This circuit monitors VDD for undervoltage. If the VDD input falls below the detector threshold (VDET−), then the capacitor on the CD pin will be immediately discharged resulting in the reset output changing to its active state indicating that an undervoltage event has been detected. The addition of a logic gate (Logic 1) provides for reset output control which is independent of VDD. If the output of the logic gate is tristated the undervoltage detector will behave normally. If the tristate is de−asserted, the logic gate will pull the CD pin low resulting in the Reset Output pin changing to an active state. This independent control is useful in power supply sequencing applications when the Reset Output is tied to the enable input of an LDO or DC−DC converter. http://onsemi.com 20 NCP302, NCP303 Power Supply 1 (System Core) R1 is Optional CD Pin Pullup 2 R1 5 CD CD NCP302L Series 3 GND 1 Reset Output *Required for NCP303 Input * RP To MCU or Logic Circuitry VP 3.3 V Power Supply 2 (I/O Subsystem) 2 Input 1 Reset Output NCP301 LSN30T1 3 5.0 V Power Supply 3 (Peripheral Subsystem) GND 2 Input 1 Reset Output NCP301 LSN45T1 3 GND VIN Power Supply 1 0V Power Supply 2 0V Power Supply 3 0V CD Pin VIN VTCD 0V NCP302L RESET Output 0V Note: VTCD  0.675 * VIN tD2 tD2 tD2 tD2 Figure 46. Multi−Rail Supply Undervoltage Monitor with Power Good This circuit monitors multiple power supply rails for undervoltage conditions. If any of the three power supplies are in an undervoltage condition, the NCP302 reset output will be immediately set to an active low level. All three power supplies must be above their minimum voltage levels for the NCP302 reset output to generate a “Power Good” level (Reset Output = Power Supply 1 or VP). Optionally, R1 may be added to provide a smaller effective CD pin pullup resistance, (RD’), where RD’ = R1 || RD, with RD (internal CD pin pullup resistance) approximately equal to 1.0 MW, and R1 > 5 kW. If R1