五,产品封装图 (Package)

六.电路原理图


七,功能概述
General
 
The JTMA7095/A provides voltage-mode feedback con-trols for six DC/DC PWM converters
(CH1 to CH6). Each channel operates with an error amplifier, PWM comparator,short-circuit
comparator, ON/OFF control, and output driver. An internal temperature-compensated voltage
pro-vides reference voltages for each channel. An triangular-wave oscillator(CT) with a timing
resistor and capacitor generates triangular waves to each channel. A inverting amplifier(CH4)
cooperates with the error amplifier for an inverting converter (with negative output voltage) .
 
Reference Voltage
 
The JTMA7095 outputs a temperature- compensated ref-erence voltage(2.49V) at VREF pin.
It is regulated from the voltage at VCC pin and can source current of max.1mA to external loads.
It also supplies bias for the IC’s internal circuitry.
 
Triangular-wave Oscillator
The triangular-wave oscillator is designed to generates a triangular oscillation signal (CT) with amplitude
of 0.3V~0.8V at CT pin, providing signal to CH6. The oscilla-tor frequency is settable from 100kHz to 1MHz
and set by a timing resistor and a timing capacitor connected re-spectively from RT and CT pins to ground.
Additional two triangular oscillation signals (CT1 and CT2) are also in-ternally generated with amplitude of
1.1V~1.8V. The CT1 is in phase with the CT to the PWM comparators of CH2 and CH4; the CT2 is out of
phase with the CT to the PWM comparators of CH1, CH3, and CH5.
 
Error Amplifier
The error amplifier is designed with unit-gain-bandwidth of 1MHz and to satisfy wide application requirements. It
works with enternal resistor-capacitor network for each converter’s feedback compensation. The loop gain can
be set by connecting a feedback resistor and capacitor from the output pin(FB) to inverted input pin of the error
amplifier for stable operations.
 
Inverting Amplifier (Inv Amp)
The inverting amplifier detects the inverting DC/DC con-verter output voltage (as a negative voltage) and outputs a
control signal to the error amp.