LT1106
OBSOLETE:
Contact Linear Technology for Potential Replacement
FOR INFORMATION PURPOSES ONLY
Micropower Step-Up
DC/DC Converter for
PCMCIA Card Flash Memory
The LT
®
1106 is the industry’s first DC/DC converter
designed for use on Type I and Type II PCMCIA cards. The
device senses the VPP1 and VPP2 lines at the PCMCIA
socket and generates a regulated 12V, 60mA program-
ming supply if the socket does not provide it. Internal logic
simplifies the interface to PCMCIA card microcontrollers.
One input selects a 12V or 5V regulated output, while
another input controls micropower shutdown. Two logic
outputs indicate when the selected programming voltage
is valid and whether the input supply is 3.3V or 5V.
The regulator features Burst Mode
TM
operation with a 0.5A,
300mV switch for efficiency up to 85%. High frequency
500kHz switching permits the use of small value, flat
inductors that fit neatly on PCMCIA cards. The device
requires just 1µF of output capacitance.
Quiescent current is 750µA which drops to 350µA when
the card runs off the socket supply. The shutdown pin
reduces supply current to only 10µA. The device includes
a soft start feature which limits supply current transients
when the card is inserted into a hot socket.
, LTC and LT are registered trademarks of Linear Technology Corporation.
Burst Mode is a trademark of Linear Technology Corporation.
FEATURES
I
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I
I
I
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60mA Output Current at 12V from 3V Supply
Shutdown to 10µA
Programmable 12V or 5V Output
Up to 85% Efficiency
Quiescent Current: 750µA
Low V
CESAT
Switch: 300mV at 0.5A Typical
Uses Low Value, Thin, Surface Mount Inductors
Ultra-Thin 20-Lead TSSOP Package
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PCMCIA Card Flash Memory VPP Generator
Portable Computers
Portable Instruments
DC/DC Converter Module Replacements
12V, 60mA Flash Memory Programming Supply
V
CC
3.3V/5V
L1*
10µH
D1**
86
84
82
EFFICIENCY (%)
+
4.7µF
TANT
ALUM
0.1µF
0.1µF
D
BSS84
S
V
CC
VPP1
G1
VPP2
G2
LT1106
VPP VALID
3/5 DETECT
SW
AVPP
1µF
VPP VALID
3/5
12V/60mA
VPP1
VPP2
0.1µF
D
BSS84
S
POWER ON
*DALE ILS-3825-01 OR
COILTRONICS CTX02-11238-3
**MOTOROLA MBR0530
UO
TYPICAL APPLICATI
UO
APPLICATI
S
470pF
SOFT START
ON/OFF
12/5
PGND GND
1M
0.1µF
LT1106 • TA01
U
12V Output Efficiency
D1 = MBR0530
D1 = 4 BAT54Cs
IN PARALLEL
V
IN
= 5V
V
IN
= 5V
V
IN
= 3.3V
V
IN
= 3.3V
80
78
76
74
72
70
1
10
LOAD CURRENT (mA)
100
LT1106 • TA02
DESCRIPTIO
1
LT1106
ABSOLUTE
AXI U
RATI GS
PACKAGE/ORDER I FOR ATIO
TOP VIEW
SELECT 12/5
SOFT START
V
CC
V
CC
3/5
PGND
PGND
NC
V
SW
1
2
3
4
5
6
7
8
9
20 ON/OFF
19 AVPP
18 VPP1
17 VPP2
16 G1
15 G2
14 VPP VALID
13 GND
12 NC
11 V
SW
V
CC
Voltage............................................................... 7V
V
SW
Voltage ............................................................ 20V
AVPP Voltage ......................................................... 20V
VPP1, VPP2 Voltage ............................................... 20V
G1, G2 Voltage ....................................................... 20V
V
ON/OFF
Voltage......................................................... 7V
V
SEL
Voltage ............................................................. 7V
I
LIM
Voltage .............................................................. 7V
Maximum Power Dissipation ............................ 500mW
Operating Temperature Range ..................... 0°C to 70°C
Storage Temperature Range ................. – 65°C to 150°C
Lead Temperature (Soldering, 10 sec).................. 300°C
ORDER PART
NUMBER
LT1106CF
V
SW
10
F PACKAGE
20-LEAD PLASTIC TSSOP
T
JMAX
= 100°C,
θ
JA
= 90°C/W
Consult factory for Industrial and Military grade parts
ELECTRICAL CHARACTERISTICS
SYMBOL
I
Q
PARAMETER
Quiescent Current
Quiescent Current, Shutdown
“Doze” Mode Current
Input Voltage Range
Output Sense Voltage
Output Referred
Comparator Hysteresis
f
OSC
DC
t
ON
V
CESAT
Oscillator Frequency
Maximum Duty Cycle
Switch On-Time
Reference Line Regulation
Switch Saturation Voltage
Switch Leakage Current
Switch Current Limit
Soft Start Pin Current
Select Input Voltage Low
Select Input Voltage High
ON/OFF Input Voltage Low
ON/OFF Input Voltage High
ON/OFF Bias Current
T
A
= 25°C, V
CC
= 5V, V
ON/OFF
= 3V, unless otherwise noted.
MIN
TYP
750
9
320
2
6
5
12
15
35
400
q
q
q
CONDITIONS
V
SEL
= 0.2V, AVPP = 12V
V
ON/OFF
= 0.2V
V
SEL
= 0.2V, VPP1 or VPP2 = 12V
V
SEL
= 3V, VPP1 and VPP2 Floating
V
SEL
= 0.2V, VPP1 and VPP2 Floating
V
SEL
= 3V
V
SEL
= 0.2V
Current Limit Not Asserted
MAX
900
15
UNITS
µA
µA
µA
V
V
V
mV
mV
4.75
11.50
5.25
12.60
500
85
1.7
0.06
230
0.1
700
92
0.15
350
10
900
950
120
0.8
80
2V < V
IN
< 6V
I
SW
= 0.5A
V
SW
= 12V, Switch Off
V
IN
= 5V, Soft Start Floating
V
IN
= 3V, Soft Start Floating
Soft Start Grounded
1.6
450
500
600
650
80
0.8
1.6
V
ON/OFF
= 5V
V
ON/OFF
= 3V
V
ON/OFF
= 0V
16.0
8.0
0.1
24.0
14.0
1.1
2
U
kHz
%
µs
%/V
mV
µA
mA
mA
µA
V
V
V
V
µA
µA
µA
W
U
U
W W
W
LT1106
ELECTRICAL CHARACTERISTICS
SYMBOL
PARAMETER
Select Pin Bias Current
VPP1/VPP2 Input Sense Threshold
AVPP Pin Input Current
T
A
= 25°C, V
CC
= 5V, V
ON/OFF
= 3V, unless otherwise noted.
MIN
11.0
TYP
0.1
11.5
50
0.1
50
0.1
q
CONDITIONS
0V < V
SEL
< 5V
MAX
1
11.9
90
1
90
1
12
0.3
4.2
0.9
1
UNITS
µA
V
µA
µA
µA
µA
V
V
V
V
V
V
µA
V
ON/OFF
= 0.2V
VPP1/VPP2 Pin Input Current
V
ON/OFF
= 0.2V
VPP VALID Threshold
VPP VALID Output Voltage Low
VPP VALID Output Voltage High
3/5 Comparator Threshold
3/5 Comparator Output High
3/5 Comparator Output Low
Off State Current at G1/G2
I
LOAD
= 50µA
I
LOAD
= 50µA
VPP1 = 10V, VG1 = 12V or VPP2 = 10V,
VG2 = 12V or V
ON/OFF
= 0V
AVPP Rising (High to Low Transition)
I
SINK
= 100µA
I
SOURCE
= 2.5µA
q
11.4
0.13
4
3.6
3.65
4.5
3.75
3.8
0.75
0.1
The
q
denotes specifications which apply over the full operating
temperature range.
TYPICAL PERFORMANCE CHARACTERISTICS
Oscillator Frequency
800
OSCILLATOR FREQUENCY (kHz)
1000
SWITCH SATURATION VOLTAGE (mV)
900
SWITCH CURRENT (mA)
800
V
CC
= 3V
700
V
CC
= 5V
600
500
400
–50
700
600
500
400
300
–50
–25
0
25
50
TEMPERATURE (°C)
U W
75
LT1106 • TPC01
Switch Current Limit
250
Switch Saturation Voltage
I
SW
= 500mA
225
200
175
150
125
100
–50
100
–25
0
25
50
TEMPERATURE (°C)
75
100
–25
0
25
50
TEMPERATURE (°C)
75
100
LT1106 • TPC02
LT1106 • TPC03
3
LT1106
TYPICAL PERFORMANCE CHARACTERISTICS
3/ 5 Comparator Threshold
4.00
3.95
AVPP SENSE VOLTAGE (V)
12.10
12.05
12.00
11.95
11.90
11.85
3.90
3.85
3.80
3.75
3.70
–50
AVPP SENSE VOLTAGE (V)
THRESHOLD VOLTAGE (V)
–25
0
25
50
TEMPERATURE (°C)
Supply Current in Shutdown
14
12
SUPPLY CURRENT (µA)
10
8
6
4
2
0
–50
V
CC
= 3V
V
CC
= 5V
SUPPLY CURRENT (µA)
V
CC
= 5V
V
CC
= 3V
MAXIMUM DUTY CYCLE (%)
–25
50
25
0
TEMPERATURE (°C)
Start-Up Waveforms, I
LOAD
= 1mA
12V
VAVPP
2V/DIV
VPP VALID
10V/DIV
ON/OFF
10V/DIV
50µs/DIV
LT1106 • TPC10
4
U W
75
LT1106 • TPC04
AVPP Sense Voltage
12.20
12/5 SELECT = 0
12.15
5.05
5.00
4.95
4.90
4.85
5.10
AVPP Sense Voltage
12/5 SELECT = 1
100
11.80
–50
–25
50
25
TEMPERATURE (°C)
0
75
100
4.80
–50
–25
0
25
50
TEMPERATURE (°C)
75
100
LT1106 • TPC05
LT1106 • TPC06
Supply Current
800
95
Maximum Duty Cycle
700
90
600
85
500
80
400
75
75
100
300
–50
–25
0
25
50
TEMPERATURE (°C)
75
100
70
–50
–25
0
25
50
TEMPERATURE (°C)
75
100
LT1106 • TPC07
LT1106 • TPC08
LT1106 • TPC09
Start-Up Waveforms with Soft
Start, I
LOAD
= 10mA
V
OUT
5V/DIV
12V OUTPUT
1V/DIV
AC COUPLED
I
LOAD
60mA
10mA
Load Transient Response,
C
OUT
= 1µF
I
L
500mA/DIV
V
ON/OFF
10V/DIV
50µs/DIV
LT1106 • TPC11
50µs/DIV
LT1106 • TPC12
LT1106
PI FU CTIO S
SELECT 12/5 (Pin 1):
Tie to V
IN
or logic 1 for 5V output;
tie to GND or logic 0 for 12V output.
SOFT START (Pin 2):
A 0.1µF/1MΩ parallel RC from this
pin to GND provides a Soft Start function upon device
turn-on. Initially about 80µA will flow from the pin into the
capacitor. When the voltage at the pin reaches approxi-
mately 0.4V, current ceases flowing out of the pin. See
Applications Information section.
V
CC
(Pins 3, 4):
Input Supply. Both pins should be tied
together. At least 1µF input bypass capacitance is re-
quired. More capacitance reduces ringing on the supply
line.
3/5 (Pin 5):
Supply Comparator Output. This pin provides
logic output indicating the value of the input supply. High
when V
CC
= 5V; low when V
CC
= 3.3V.
PGND (Pins 6, 7):
Power Ground. Connect to ground plane.
V
SW
(Pins 9, 10, 11):
Collector of Power Switch. High dV/
dt present on this pin. To minimize radiated noise keep
layout short and direct.
GND (Pin 13):
Signal Ground. Connect of ground plane.
VPP VALID (Pin 14):
This pin provides a logic signal
indicating that ouput voltage is greater than 11.4V. Active
low with internal 200k pull-up resistor.
G1, G2 (Pins 16, 15):
External MOSFET Gate Drives. When
VPP1 or VPP2 is greater than 11.7V, G1 or G2 is driven to
about 0.8V. When VPP1 or VPP2 is less than 11.7V, the
drives assume a high impedance state pulled up to the
AVPP pin through an internal 100k resistor.
VPP1, VPP2 (Pins 18, 17):
Programming Power Inputs.
The LT1106 senses both VPP1 and VPP2 supplies at the
PCMCIA card socket. If VPP1 or VPP2 is greater than 11V,
the LT1106 operates in “Doze” Mode — the switching
regulator turns off and the drive to external P-channel
MOSFETs turns on. Supply current in Doze Mode is about
350µA. Input current into VPP1 and VPP2 is about 1µA
when the device is shut down.
AVPP (Pin 19):
Output Sense Pin. This pin connects to a
1MΩ resistive divider that sets the output voltage. In
shutdown, the resistor string is disconnected and current
into this pin is reduced to < 1µA.
ON/OFF (Pin 20):
Shutdown Control. When pulled below
1.5V, this pin disables the LT1106 and reduces supply
current to 10µA. All circuitry except the 3/5 comparator
is disabled in shutdown. The part is enabled when
ON/OFF is greater than 1.5V.
U
U
U
5