IR35201MTYPBF datasheet(29/60 Pages) IRF

29 / 60 page

8+0/7+1/6+2 Dual Output Digital Multi-Phase Controller

IR35201

February 8, 2015 | V1.6

Figure 25: Load Line & Thermal Compensation for DCR Sense

Figure 26 Load Line for RDS (ON) Current Sense

The resistor RCS is calculated using the following

procedure:

Calculate the RCSeffective or the total effective

parallel resistance across the RSCP and

RCSM pins as defined by:

DCR

ISEN

effective





where RLL is the desired load line, DCR is DC

resistance of the phase inductor, and R_ISEN is the

internal series resistor = 1000

.

Select a suitable NTC thermistor, Rth. This is

typically selected to have the lowest thermal

coefficient and tightest tolerance in a standard

available package. A typical NTC used in

these applications is a 10kΩ, 1% tolerance

device. Recommended thermistors are shown

in Table 18.

TABLE 18: 10K 1% NTC THERMISTORS

Murata

NCP18XH103F03RB

Panasonic

ERTJ1VG103FA

TDK

NTCG163JF103F

Calculate RCS using the following equation:

series

effective









Rseries is selected to achieve minimum load line error

over temperature. The IR PowIRCenter GUI provides

a graphical tool that allows the user to easily calculate

the resistor values for minimum error.

The capacitor CCS is defined by the following equation:

AVP

effective







where fAVP is the user selectable current sense AVP

bandwidth. The recommended bandwidth is typically

in the range of 200kHz to 300kHz.

RDS (ON) Current Sense

IR35201 reads the current value from individual power

stages as shown in Figure 22. The power stage

measures the output current by sensing the voltage

drop across lower side MOSFET. The current sensed

by the power stage is thermally compensated hence

there is no need of an external thermistor for

temperature compensation. Thus, RDS (ON) current

sense reduces the component count required for

loadline measurement as shown in Figure 26.

The resistor Rcs for RDS ON current sense is calculated

by using the following procedure.

=8∗ ∗ /( ∗)

Where IRDS ON Scale = current scale of Power Stage in

V/A

Divider Ratio =

.Refer to Figure 22

The capacitor CCS is defined by the following equation:

AVP







IR35201MTYPBF Datasheet(PDF) 29 Page - International Rectifier

IR35201MTYPBF Datasheet(HTML) 29 Page - International Rectifier

Html Pages

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60

Datasheet Download

Link URL