LV5604T

No.A0966-10/12

Continued from preceding page.

Pin No.

Pin Name

Description

Equivalent Circuit

46

VCC

Signal system power supply

2

47

VBIAS1

VBIAS2

Power system power supply

(Output stage)

24

GND_S

Signal system GND

58

54

GND_P1 (VS1)

GND_P2 (VS2)

Output stage GND

(Output stage GND)

50

63

(NC)

(NC)

Use prohibited

(Not connected pins)

Notes

(1) Channel 8 step-up/step-down selection function

The channel 8 step-up or step-down converter selection is made by the SEL_8CH pin connection.

Step-up/step-down is selected by SEL_CH8, but this selection cannot be switched during use, and is fixed to either

step-up or step-down in the design stage. In addition, unlike other channels, channel 8 is not connected internally to a

pull-up/pull-down resistor, so an external resistor must be connected instead.

(Mode selection using SEL_CH8)

Selected mode

SEL_CH8 connection

OUT8 resistor connection

Step-down (DOWN converter)

VBIAS2

Connect to VBIAS2 via a resistor (between the PchTr gate and VBIAS2)

Step-up (UP converter)

GND_P2 (VS2)

Connect to GND_P2 (VS2) via a resistor

(between the NchTr gate and GND_P2 (VS2))

(2) Soft start time setting method

The soft start time is set with the capacitor connected between CSOFT* and GND_S.

This IC has an independent soft start function for each channel, so a capacitor must be connected for each channel to

set the soft start (time).

(Description of soft start operation)

(Outline of soft start pin)

(3) Setting the oscillation frequency

The internal oscillation frequency is set by the resistor connected to the RT pin and the capacitor connected to the CT

pin. The waveform generated on CT is a triangular wave with the charging/discharging waveform determined by RT

and CT.

fOSC =

1

CT × RT

[Hz]

The actual internal oscillation frequency deviates from the calculated value due to overshoot, undershoot and other

factors, so the frequency should be confirmed in an actual set.

CSOFT* [V]

CSOFT* voltage

VREG

(Internal constant voltage)

T [s]

VB (0.515 [V])

200k

Ω

CSOFT*

GND_S

VB ( = 0.515 [V] (TYP))

CSOFT pin

charging starts

The output voltage reaches the

set voltage

(Output voltage constant)

Soft start time (Tsoft [s])

VCC

VBIAS*

GND_S

GND_P*(VS*)

(NC)