MB39A102_05 Datasheet, PDF (14/32 Pages) Tyco Electronics – 4-ch DC/DC Converter IC

MB39A102
■ SETTING THE OUTPUT VOLTAGE
• CH1 to CH4
VO
R1
−INEx
R2
CSx
Error
− ^Amp
+
+
1.24 V
VO (V) = ^1.24
R2
(R1 + R2)
x : Each channel No.
■ SETTING THE TRIANGULAR OSCILLATION FREQUENCY
The triangular oscillation frequency is determined by the timing capacitor (CT) connected to the CT terminal (pin
9), and the timing resistor (RT) connected to the RT terminal (pin 8).
Moreover, it shifts more greatly than the calculated values according to the constant of timing resistor (RT) when
the triangular wave oscillation frequency exceeds 1 MHz. Therefore, set it referring to “Triangular Wave Oscillation
Frequency vs. Timing Resistor” and “Triangular Wave Oscillation Frequency vs. Timing Capacitor” in “■ TYPICAL
CHARACTERISTICS”.
Triangular oscillation frequency : fOSC
fOSC (kHz)
=:
1200000
CT (pF) × RT (kΩ)
14