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1.5V drive MOSFETs for portable devices ECOMOS series
ROHM's ECOMOSTM is a power MOSFET specifically designed for use in the power circuits of portable devices. Special emphasis was made to reduce power consumption by significantly reducing ON-resistance during operation for longer battery life. Every effort was made to minimize environmental impact, including the use of halogen-free resins.
Power MOSFET requirements

Portable device development has reached a point where a dizzying array of functions is built into a device no bigger than a palm. ‘Compact’, ‘lightweight’, and ‘long battery life’ have become much more than mere catchwords – they often spell the difference between success and failure for a portable product in the highly competitive consumer electronics sector. ROHM offers components that meet these needs without sacrificing functionality or reliability.

Drastically reduced MOSFET ON-resistance
Ideally, the power consumption for power MOSFETs used as ON/OFF switches on power supply lines to circuit blocks 0W. However, this is not the case due to the internal ON-resistance (P(loss) = RDS(on) × I2). Therefore, reducing ON-resistance is critical for reducing power consumption. ROHM’s ECOMOSTM series features a submicron cell pitch structure, developed using microfabrication technology. This increases current capacity per unit area to approximately 2.5 times that of conventional products, resulting in lower ON-resistance. The lineup is offered in several voltage ratings for optimum compatibility.
Low 1.5V drive
Conventional ON/OFF switches in 1.5V power lines use step-up drives with level shift circuits or bipolar transistors to drive 1.8V or 2.5V power MOSFETs, increasing power consumption. However,ROHM, through process optimization, has achieved a Gate-Source voltage drive (VGS) of 1.5V, enabling direct drive from 1.5V lines,reducing not only power consumption but the number of external components. In addition, using low-voltage drive contributes to a reduction in the ON-resistance of other drive voltage regions (VGS= 1.8V/2.5V/4.5V), making it is superior to conventional 1.8V and 2.5V drive power MOSFETs (Figure 1).
Figure 1. VGS–RDS(on) Characteristics Comparison:2.5V Drive vs. 1.5V Drive
Figure 1. VGS–RDS(on) Characteristics Comparison: 2.5V Drive vs. 1.5V Drive
Compact, high-power package with high heat resistance
Recently batteries have become more compact and thinner,while increasingly precise heat design dissipates heat generated by the power MOSFET outside of the case. In response to this trend ROHM has developed new compact, high power packages optimized for battery charge control compatible with several hundred mW.(Figure 2)


Figure 2. Packages Optimized for Portable Devices
Figure 2. Packages Optimized for Portable Devices
Ideal circuit for portable devices

ECOMOSTM offers a variety of advantages to the device designer
when used in various portable device circuitry, such as dual Pch
configuration for switching between the adapter and secondary
lithium ion battery in charge control blocks, or an integrated
Schottky barrier diode for reverse current prevention that simplifies
circuit design.

circuit

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ECOMOSTMLineup
Package(mm) PD(W) Polarity Part No. VDSS(V) ID(A) RDS(ON)Typ.(mΩ)
VGS=1.5V VGS=4.5V
VMT3
(1.2×1.2×0.5)		 VMT3 0.15 Nch NewRUM003N02 20

0.3

1*1

0.7*2
EMT3
(1.6×1.6×0.7)		 EMT3 3.0 to 3.6 Nch NewRUE003N02 20

0.3

 1*1 0.7*2
EMT6
(1.6×1.6×0.5)		 EMT6 3.0 to 3.6 Nch+Nch NewEM6K6 20

0.3

 1*1 0.7*2
TUMT3
(2.0×2.1×0.77)		 TUMT3 0.8 Nch NewRUF015N02 20

1.5

 220*1 130
NewRUF025N02 20

2.5

 80 39
Pch NewRZF030P01 -12 -3 72 28
TUMT6
(2.0×2.1×0.77)		 TUMT6 1 Nch NewRUL035N02 20 3.5 66 31
Pch NewRZL035P01 -12 -3.5 66 26
Nch+Nch NewUS6K4 20 1.5 220*1 130
TSMT3
(2.9×2.8×0.85)		 TSMT3 1 Nch NewRUR040N02 20 4 55 23
Pch NewRZR040P01 -12 -4 55 22
TSMT6
(2.9×2.8×0.85)		 TSMT6 1.25 Nch NewRUQ050N02 20 5 40 22
Pch NewRZQ050P01 -12 -5 44 19
TSMT8
(3.0×2.8×0.8)		 TSMT8 1.5. Pch NewRQ1A070ZP -12 -7 19 8
Pch+Pch NewQS8J1 -12 -4.5 49 21
TSST8
(3.0×1.9×0.8)		 TSST8 1.25 Pch NewRT1A050ZP -12 -5 48 19
Pch+Pch NewTT8J1 -12 -2.5 110 44
Pch+SBD NewTT8U1 -20 -2.4 180 80
WEMT6
(1.6×1.6×0.6)		 WEMT6 0.7 Nch+SBD NewES6U41 30 1.5 240*3 170
Pch+SBD NewES6U42 -20

-1

 570*3 280
*1VGS=1.8V　*2VGS=4V　*3VGS=2.5V