UCC2808A-2Q1

Features:

 Qualification in Accordance With AEC-Q100†
 Qualified for Automotive Applications
 Customer-Specific Configuration Control Can Be Supported Along With Major-Change Approval
 ESD Protection Exceeds 1500 V Per MIL-STD-883, Method 3015; Exceeds 200 V Using Machine Model (C = 200 pF, R = 0)
 Dual Output Drive Stages in Push-Pull Configuration
 Current Sense Discharge Transistor to Improve Dynamic Response
 130-A Typical Starting Current
 1-mA Typical Run Current
 Operation to 1 MHz
 Internal Soft Start
 On-Chip Error Amplifier With 2-MHz Gain Bandwidth Product
 On Chip VDD Clamping
 Output Drive Stages Capable of 500-mA Peak-Source Current, 1-A Peak-Sink Current


Pinout




Specifications

Supply voltage (IDD 10 mA) . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. . . . . . . . . . . . . . . 15 V
Supply current . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. . . . . . . . . . . 20 mA
OUTA/OUTB source current (peak) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . −0.5 A
OUTA/OUTB sink current (peak) . . . . . . . . . . . . . . . . . .. . . . . . . . . . . . . . . . . . . . . . . . . 1.0 A
Analog inputs (FB, CS) . . . . . . . . . . . . . . . . . . . . . . . −0.3 V to VDD 0.3 V, not to exceed 6 V
Power dissipation at T_A = 25°C (D package) . . . . . . . . . . . . . . . . . . . . . ...... . . . . . 650 mW
Power dissipation at T_A = 25°C (PW package) . . . . . . . . . . . . . . . . . . . . . . . . . . . . 400 mW
Storage temperature, T_stg . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. . . −65°C to150°C
Junction temperature, T_J . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .  . . . −55°C to 150°C
Lead temperature (soldering, 10 sec.) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. . . . . 300°C

Description

The UCC2808A is a family of BiCMOS push-pull, high-speed, low-power, pulse-width modulators. The UCC2808A contains all of the control and drive circuitry required for off-line or dc-to-dc fixed frequency current-mode switching power supplies with minimal external parts count.

The UCC2808A dual output drive stages are arranged in a push-pull configuration. Both outputs switch at half the oscillator frequency using a toggle flip-flop. The dead time between the two outputs is typically 60 ns to 200 ns depending on the values of the timing capacitor and resistors, thus limiting each output stage duty cycle to less than 50%.

The UCC2808A family offers a variety of package options and choice of undervoltage lockout levels. The family has UVLO thresholds and hysteresis options for off-line and battery powered systems. Thresholds are shown in the ordering information table.

The UCC2808A is an enhanced version of the UCC2808 family. The significant difference is that the A versions feature an internal discharge transistor from the CS pin to ground, which is activated each clock cycle during the oscillator dead time. The feature discharges any filter capacitance on the CS pin during each cycle and helps minimize filter capacitor values and current sense delay.