Instruction Manual

Introduction
1-2
1.1 Introduction
The UCC2977 EVM (SLUP178) is a 1.8-W dc/ac inverter module used to drive
a cold cathode fluorescent lamp (CCFL) with a piezoelectric transformer
(PZT). This EVM consists of a push-pull circuit using the UCC2977 controller.
The principle of operation for the inverter is explained in the application section
of the UCC2977 data sheet.
1.2 Operating Specifications
This section summarizes the performance specifications of the SLUP178
converter. Table 1–1 lists the operating specifications for the SLUP178.
Table 1–1.Operating Specifications
Input voltage (V
IN
) 3~6 Vdc
Output voltage (Lamp_HV, Lamp LV) 300 Vac, rms
Output current (lamp current) 4.7 mA, rms
Operating frequency (kHz) 100 kHz
Burst dimming (BD )
†
Square wave, 120 Hz, 0 to 3 V
Analog dimming (AD) 0~3 Vdc
CCFL lamp JKL BF3100–20B (100 mm, 270 V
RMS
)
†
Use a function generator.