Datasheet CAT4101 (ON Semiconductor) - 7
| Manufacturer | ON Semiconductor |
| Description | 1 A Constant-Current LED Driver with PWM Dimming |
| Pages / Page | 10 / 7 — CAT4101. Block Diagram. Figure 15. CAT4101 Functional Block Diagram. … |
| File Format / Size | PDF / 220 Kb |
| Document Language | English |
CAT4101. Block Diagram. Figure 15. CAT4101 Functional Block Diagram. Basic Operation. Table 6. RSET RESISTOR SETTINGS
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CAT4101 Block Diagram
VIN LED Undervoltage & Thermal VIN Lockout EN/PWM Shutdown Delay Reference Voltage Current Regulator RSET RSET Regulator & Mirror GND
Figure 15. CAT4101 Functional Block Diagram Basic Operation Table 6. RSET RESISTOR SETTINGS
The CAT4101 has one highly accurate LED current sink to regulate LED current in a string of LEDs. The LED
LED Current [mA] RSET [W]
current is mirrored from the current flowing from the RSET 100 4990 pin. Table 6 lists various RSET resistor values for LED 200 2490 current in 100 mA increments. 300 1690 The LED channel needs a minimum of 500 mV headroom to sink constant regulated current. If the input supply falls 400 1270 below 2 V, the under−voltage lockout circuit disables the 500 1050 LED channel. 600 866 For applications requiring current higher than 1 A, several 700 768 CAT4101 devices can be connected in parallel. The LED channel can withstand and operate at voltages 800 680 up to 25 V. This makes the device ideal for driving long 900 604 strings of high power LEDs from a high voltage source. 1000 549
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CAT4101 Block Diagram
VIN LED Undervoltage & Thermal VIN Lockout EN/PWM Shutdown Delay Reference Voltage Current Regulator RSET RSET Regulator & Mirror GND
Figure 15. CAT4101 Functional Block Diagram Basic Operation Table 6. RSET RESISTOR SETTINGS
The CAT4101 has one highly accurate LED current sink to regulate LED current in a string of LEDs. The LED
LED Current [mA] RSET [W]
current is mirrored from the current flowing from the RSET 100 4990 pin. Table 6 lists various RSET resistor values for LED 200 2490 current in 100 mA increments. 300 1690 The LED channel needs a minimum of 500 mV headroom to sink constant regulated current. If the input supply falls 400 1270 below 2 V, the under−voltage lockout circuit disables the 500 1050 LED channel. 600 866 For applications requiring current higher than 1 A, several 700 768 CAT4101 devices can be connected in parallel. The LED channel can withstand and operate at voltages 800 680 up to 25 V. This makes the device ideal for driving long 900 604 strings of high power LEDs from a high voltage source. 1000 549
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