P r o d u c t I n n o v a t i o n F r o m

MP400

4

MP400U

Pin #

Pin name

Description

21 - 23, 25 V

IN

Input voltage pins for the on board high voltage switch mode power supply.

24

V

BIAS

Input voltage pin for the boost controller circuitry. This pin is typically tied to V

IN

12 – 15

Q2D

Drain node of the SMPS MOSFET switch. An external RC snubber may be connect from this

node to power ground to reduce or eliminate overshoot and ringing at switch turn off, reducing

switching noise on the SMPS.

8

V

B

This is the output of the high voltage SMPS and typically is tied to pin 6, L

be added to this pin as long as the maximum output power of the SMPS is not exceeded. For

proper operation, an external high voltage, low ESR capacitor must be connected to this pin.

Refer to the paragraph titled “SMPS Output Capacitor”.

6

L

FIN

The high voltage SMPS, V

47 µH filter inductor. The supply current in to this pin can not exceed 200 mA.

4

+V

S

MP400FC amplifier high voltage supply pin. This pin is used for external supply bypass. A high

quality ceramic capacitor of at least 1uF should be used. The high voltage SMPS, V

connected directly to this pin, bypassing the 47 µH filter inductor.

34

R

SET

SMPS voltage set resistor. A resistor is connected from this pin to power ground to set the SMPS

voltage.

26 – 33

PGND

Power ground. SMPS switching circuits are referenced to ground through these pins.

35

AGND

Analog ground for MP400FC amplifier circuits. AGND and PGND are connected at one point on

the MP400FC. Avoid external connections between AGND and PGND.

41

-V

S

This pin is typically connected to AGND. However, an external negative supply voltage can be

connected to this pin.

39

+IN

Amplifier non-inverting input

40

-IN

Amplifier inverting input

1

V

OUT

Amplifier output

2

I

LIM

Amplifier current limit. A current limit resistor must be connected between I

0.7/I

36

C

+ side compensation capacitor connection one.

37

C

+ side compensation capacitor connection two.

38

C

- side compensation capacitor connection one.

42

C

- side compensation capacitor connection two.

Unused pins should be left open. This is mandatory for pins 3, 5, 7, 9, 11 and 16.

tyPical aPPlication

The MP400FC is ideally suited to driv-

ing both piezo actuation and deflection

applications off of a single low volt-

age supply. The circuit above boosts a

system 24 V buss to 350 V to drive an

ink jet print head. The MP400FCs high

speed deflection amplifier is biased for

single supply operation by external re-

sistors R2 – R6, so that a 0 to 5 V DAC

can be used as the input to the amplifier

to drive the print head from 0 to >300 V.

R1

402K

R

CL

DEFLECTION

PLATE

INK

DROPLETS

SMPS

CIRCUIT

Vin = 24V

0-5V

DAC

MP400

C

C

C

C

+350V

R2

124K

1W

R3

124K

1W

R6

402K

R5

5.62K

R4

5.62K

0.0Ω

470µF

100µF

Rset

PGND

Vboost

Pin DescriPtions