TL3844D

Product Summary

The TL3844D is a current-mode pwm controller.The TL3844D series of control integrated circuits provide the features that is necessary to implement off-line or dc-to-dc fixed-frequency current-mode control schemes with a minimum number of external component. Some of the internally implemented circuits are an undervoltage lockout (UVLO), featuring a start-up current of less than 1 mA, and a precision reference trimmed for accuracy at the error amplifier input. Other internal circuits include logic to ensure latched operation, a pulse-width modulation (PWM) comparator (which also provides current-limit control), and a totem-pole output stage designed to source or sink high-peak current. The output stage, suitable for driving N-channel MOSFETs, is low when it is in the off state.

Parametrics

TL3844D absolute maximum ratings: (1)Supply voltage (see Note 1)(ICC < 30 mA): Self limiting; (2)Analog input voltage range, VI (VFB and ISENSE): –0.3 V to 6.3 V; (3)Output voltage, VO (OUTPUT): 35 V; (4)Input voltage, VI, (VC, D package only): 35 V; (5)Supply current, ICC: 30 mA; (6)Output current, IO: ±1 A; (7)Error amplifier output sink current: 10 mA; (8)Package thermal impedance, qJA (see Notes 2 and 3): D package: 86°C/W; (9)Package thermal impedance, qJA (see Notes 2 and 3): D-8 package 97°C/W; (10)Package thermal impedance, qJA (see Notes 2 and 3): P package 85°C/W; (11)Virtual junction temperature range, TJ: 0°C to 150°C; (12)Output energy (capacitive load): 5 mJ; (13)Lead temperature, 1,6 mm (1/16 inch)from case for 10 seconds: 260°C; (14)Storage temperature range, Tstg: –65°C to 150°C.

Features

TL3844D features: (1)Optimized for Off-Line and dc-to-dc Converters; (2)Low Start-Up Current (<1 mA); (3)Automatic Feed-Forward Compensation; (4)Pulse-by-Pulse Current Limiting; (5)Enhanced Load-Response Characteristics; (6)Undervoltage Lockout With Hysteresis; (7)Double-Pulse Suppression; (8)High-Current Totem-Pole Output; (9)Internally Trimmed Bandgap Reference; (10)500-kHz Operation; (11)Error Amplifier With Low Output Resistance; (12)Designed to Be Interchangeable With UC2842 and UC3842 Series.

Diagrams