A
DVANCED
L
INEAR
D
EVICES,
I
NC.
ALD114835/ALD114935
QUAD/DUAL N-CHANNEL DEPLETION MODE EPAD®
V
GS(th)
= -3.5V
MATCHED PAIR MOSFET ARRAYS
APPLICATIONS
• Functional replacement of Form B (NC) relay
• Zero power fail safe circuits
• Backup battery circuits
• Power failure detector
• Fail safe signal detector
• Source followers and buffers
• Precision current mirrors
• Precision current sources
• Capacitives probes
• Sensor interfaces
• Charge detectors
• Charge integrators
• Differential amplifier input stage
• High side switches
• Peak detectors
• Sample and Hold
• Alarm systems
• Current multipliers
• Analog switches
• Analog multiplexers
• Voltage comparators
• Level shifters
PIN CONFIGURATION
ALD114835
N/C*
1
2
3
4
5
6
7
8
V
-
V
-
PC, SC PACKAGES
M1
M2
e
TM
EPAD
E
N
®
AB
LE
D
GENERAL DESCRIPTION
ALD114835/ALD114935 are monolithic quad/dual N-Channel MOSFETs
matched at the factory using ALD’s proven EPAD CMOS technology. These
devices are intended for low voltage, small signal applications. They are excel-
lent functional replacements for normally-closed relay applications, as they are
normally on (conducting) without any power applied, but could be turned off or
modulated when system power supply is turned on. These MOSFETs have the
unique characteristics of, when the gate is grounded, operating in the resis-
tance mode for low drain voltage levels and in the current source mode for
higher voltage levels and providing a constant drain current.
ALD114835/ALD114935 MOSFETs are designed for exceptional device elec-
trical characteristics matching. As these devices are on the same monolithic
chip, they also exhibit excellent temperature tracking characteristics. They are
versatile as design components for a broad range of analog applications such
as basic building blocks for current sources, differential amplifier input stages,
transmission gates, and multiplexer applications. Besides matched pair electri-
cal characteristics, each individual MOSFET also exhibits well controlled pa-
rameters, enabling the user to depend on tight design limits. Even units from
different batches and different date of manufacture have correspondingly well
matched characteristics.
These depletion mode devices are built for minimum offset voltage and differ-
ential thermal response, and they are designed for switching and amplifying
applications in single 5V to +/-5V systems where low input bias current, low
input capacitance and fast switching speed are desired. These devices exhibit
well controlled turn-off and sub-threshold charactersitics and therefore can be
used in designs that depend on sub-threshold characteristics.
The ALD114835/ALD114935 are suitable for use in precision applications which
require very high current gain, beta, such as current mirrors and current sources.
A sample calculation of the DC current gain at a drain current of 3mA and gate
input leakage current of 30pA = 100,000,000. It is recommended that the user,
for most applications, connect V+ pin to the most positive voltage potential (or
left open unused) and V- and N/C pins to the most negative voltage potential
in the system. All other pins must have voltages within these voltage limits.
FEATURES
• Depletion mode (normally ON)
• Precision Gate Threshold Voltages: -3.50V +/- 0.05V
• Nominal R
DS(ON)
@V
GS
=0.0V of 540Ω
• Matched MOSFET to MOSFET characteristics
• Tight lot to lot parametric control
• Low input capacitance
• V
GS(th)
match (V
OS
) — 20mV
• High input impedance — 10
12
Ω
typical
• Positive, zero, and negative V
GS(th)
temperature coefficient
• DC current gain >10
8
• Low input and output leakage currents
ORDERING INFORMATION
Operating Temperature Range*
0°C to +70°C
0°C to +70°C
16-Pin
Plastic Dip
Package
ALD114835PC
16-Pin
SOIC
Package
ALD114835SC
8-Pin
Plastic Dip
Package
ALD114935PA
8-Pin
SOIC
Package
ALD114935SA
V
-
V
-
16
15
14
N/C*
G
N2
D
N2
V
+
S
34
D
N3
G
N3
N/C*
G
N1
D
N1
S
12
V
-
D
N4
G
N4
N/C*
V
+
V
-
M4
M3
13
12
11
10
9
ALD114935
V-
V-
N/C*
1
2
3
4
8
7
N/C*
G
N1
D
N1
S
12
G
N2
D
N2
V-
M1
M2
6
V-
5
PA, SA PACKAGES
*N/C pins are internally connected.
Connect to V- to reduce noise
* Contact factory for industrial temp. range or user-specified threshold voltage values
Rev 1.0-0506 ©2005 Advanced Linear Devices, Inc. 415 Tasman Drive, Sunnyvale, California 94089-1706 Tel: (408) 747-1155 Fax: (408) 747-1286
www.aldinc.com
ALD [ ADVANCED LINEAR DEVICES ]
