
PRODUCT SPECIFICATION
FAN1655
2
REV. 1.1.4 3/24/04
Pin Assignments
Pin Definitions
Typical Application
Pin
Pin Name
VDD
VTTFORCE
VSS
VTTSENSE
VREFIN
Pin Function Description
MLP
1, 4
2, 3
PAD
5
eTSSOP
1, 2, 7
3, 6
4, 5, 8
10
11
SOIC-14
1, 2, 7
3, 6
4, 5, 8
9
10
Input power for the LDO.
The VTT output voltage.
IC Ground.
Feedback for remote sense of the VTT voltage.
Alternative input for direct control of VTTOUT and
VREFOUT.
Shutdown. This active low shutdown turns off both VTT
and VREFOUT. This pin has an internal pull-down, and
must be externally driven high for the IC to be on.
Signal Ground.
Buffered Voltage Reference Output.
VDDQ Input. Attach this pin to the VDDQ supply to
generate VTT and VREFOUT.
No Internal Connection
Connect PAD to Vss Ground Plane
6
12
11
SHDN
13
14
15
12
13
14
VSSQ
VREFOUT
VDDQ
7
8
9, 16
PAD
NC
PAD
16
15
14
13
12
11
10
9
1
2
3
4
5
6
7
8
FAN1655
NC
VDDQ
VREFOUT
VSSQ
SHDN
VREFIN
VTTSENSE
NC
VDD
VDD
VTTFORCE
VSS
VSS
VTTFORCE
VDD
VSS
14
13
12
11
10
9
8
1
2
3
4
5
6
7
FAN1655M
VDDQ
VREFOUT
VSSQ
SHDN
VREFIN
VTTSENSE
VSS
VDD
VDD
VTTFORCE
VSS
VSS
VTTFORCE
VDD
VDDQ
VREFOUT
SHDN
VTTSENSE
VDD
VTTFORCE
VTTFORCE
VDD
GND
1
2
3
4
8
7
6
5
16-Lead Plastic eTSSOP-16
θ
JC
= 4C/W*
*Thermal impedance is measured with the
power pad soldered to a 0.5 square inch
copper area. The copper area should be
connected to Vss (ground) and positioned
over an internal power or ground plane to
assist in heat dissipation.
14-Lead Plastic SOIC
θ
JC
= 37C/W,
θ
JA
= 88C/W
8-Lead MLP Package (5x6mm)
θ
JC
= 4C/W,
θ
JA
= 34C/W as
measured on FAN1655MP
Eval Board
16
15
14
13
12
11
10
9
1
2
3
4
5
6
7
8
100
μ
F
6V
10
μ
F
GND
VDD
1nF
(connect to VTTFORCE
at the load)
VTTSENSE
470
μ
F
10
μ
F
VTTFORCE
1nF
GND
VREFOUT
SHDN
VDDQ
10k
FAN1655
Figure 1. (eTSSOP pinout shown)