LINER LTC1262 12v, 30ma flash memory programming supply Datasheet

LTC1262
12V, 30mA Flash Memory
Programming Supply
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DESCRIPTIO
FEATURES
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■
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Regulated 12V ±5% Output Voltage
No Inductors
Supply Voltage Range: 4.75V to 5.5V
Guaranteed 30mA Output
Low Power: ICC = 500µA
ICC in Shutdown: 0.5µA
8-Pin PDIP or SO-8 Package
The LTC®1262 is a regulated 12V, 30mA output DC/DC
converter. It is designed to provide the 12V ±5% output
necessary to program byte-wide flash memories. The
output will provide up to 30mA from input voltages as low
as 4.75V without using any inductors. Only four external
capacitors are required to complete an extremely small
surface mountable circuit.
The TTL compatible shutdown pin can be directly connected to a microprocessor and reduces the supply current to less than 0.5µA. The LTC1262 offers improved
shutdown current performance and requires fewer external components than competing solutions.
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APPLICATI
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S
12V Flash Memory Programming Supplies
Compact 12V Op Amp Supplies
Battery-Powered Systems
The LTC1262 is available in an 8-pin PDIP or SO-8
package.
, LTC and LT are registered trademarks of Linear Technology Corporation.
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TYPICAL APPLICATI
In/Out of Shutdown
1
C1–
SHDN
2
C1+
GND
8
FROM MPU
0.22µF
7
LTC1262
3
0.22µF
4
C2 –
C2+
VOUT
VCC
6
5
+
FLASH
MEMORY
4.7µF
SHDN 5V
5V/DIV 0V
VPP
+
4.7µF
12V
VCC
VCC
4.75V TO 5.5V
LTC1262 • TA01
VOUT
5V/DIV 5V
0V
1ms/DIV
1262 TA01a
1
LTC1262
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RATI GS
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AXI U
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ABSOLUTE
PACKAGE/ORDER I FOR ATIO
(Note 1)
Supply Voltage (VCC) ................................................ 6V
Input Voltage (SHDN) ................... – 0.3V to V CC + 0.3V
Output Current (IOUT) ........................................... 50mA
Operating Temperature Range
LTC1262C................................................ 0°C to 70°C
LTC1262I........................................... – 40°C to 85°C
Storage Temperature Range ................ – 65°C to 150°C
Lead Temperature (Soldering, 10 sec)................. 300°C
ORDER PART
NUMBER
TOP VIEW
C1– 1
8
SHDN
C1+ 2
7
GND
–
3
6
VOUT
C2 + 4
5
VCC
C2
N8 PACKAGE
8-LEAD PDIP
S8 PACKAGE
8-LEAD PLASTIC SO
LTC1262CN8
LTC1262CS8
LTC1262IS8
S8 PART MARKING
TJMAX = 150°C, θJA = 100°C/W (N8)
TJMAX = 150°C, θJA = 150°C/W (S8)
1262
1262I
Consult factory for Military grade parts.
ELECTRICAL CHARACTERISTICS
VCC = 4.75V to 5.5V, TA = – 40°C to 85°C, (Notes 2, 3), unless otherwise noted.
SYMBOL
PARAMETER
CONDITIONS
MIN
VOUT
Output Voltage
0mA ≤ IOUT ≤ 30mA, VSHDN = 0V, 0°C ≤ TA ≤ 70°C
0mA ≤ IOUT ≤ 30mA, VSHDN = 0V, – 40°C ≤ TA ≤ 85°C
●
●
ICC
Supply Current
No Load, VSHDN = 0V, 0°C ≤ TA ≤ 70°C
No Load, VSHDN = 0V, – 40°C ≤ TA ≤ 85°C
●
●
ISHDN
Shutdown Supply Current
No Load, VSHDN = VCC
fOSC
Oscillator Frequency
TYP
MAX
UNITS
12.6
12.6
V
V
0.5
0.5
1.0
1.3
mA
mA
●
0.5
10
µA
VCC = 5V, IOUT = 30mA
●
300
kHz
Power Efficiency
VCC = 5V, IOUT = 30mA
●
74
%
RSW
VCC to VOUT Switch Impedance
VCC = VSHDN = 5V, IOUT = 0mA
●
0.18
VIH
SHDN Input High Voltage
●
VIL
SHDN Input Low Voltage
●
11.4
11.2
2
2.4
kΩ
V
0.8
V
–5
–5
10
µA
µA
µA
SHDN Input Current
VCC = 5V, VSHDN = 0V, 0°C ≤ TA ≤ 70°C
VCC = 5V, VSHDN = 0V, – 40°C ≤ TA ≤ 85°C
VCC = 5V, VSHDN = 5V
tON
Turn-On Time
C1 = C2 = 0.22µF, CIN = COUT = 4.7µF, (Figures 1, 2)
500
µs
tOFF
Turn-Off Time
C1 = C2 = 0.22µF, CIN = COUT = 4.7µF, (Figures 1, 2)
3.3
ms
The ● denotes specifications which apply over the full operating
temperature range.
Note 1: Absolute maximum ratings are those values beyond which the life
of the device may be impaired.
2
●
●
●
– 20
–35
– 10
–10
0.06
Note 2: All currents into device pins are positive; all currents out of device
pins are negative. All voltages are referenced to ground unless otherwise
specified.
Note 3: All typicals are given at VCC = 5V, TA = 25°C.
LTC1262
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TYPICAL PERFORMANCE CHARACTERISTICS
Shutdown Supply Current
vs Temperature
Efficiency vs Output Current
85
3.6
EFFICIENCY (%)
80
SHUTDOWN SUPPLY CURRENT (µA)
VCC = 4.75V
VCC = 5V
75
VCC = 5.5V
70
65
60
55
0
10
3.0
2.4
1.8
1.2
0.6
0
–50
50
20
30
40
OUTPUT CURRENT (mA)
VCC = 5V
–25
0
25
50
TEMPERATURE (°C)
LTC1262 G01
Supply Current vs Supply Voltage
Output Voltage vs Output Current
12.2
IOUT = 0
12.0
580
560
540
520
TA = 25°C
TA = 0°C
4.75
5.0
5.25
5.5
SUPPLY VOLTAGE (V)
11.6
VCC = 5.5V
11.4
VCC = 5V
11.2
11.0
10.8
10.6
500
4.5
VCC = 4.75V
11.8
TA = 70°C
OUTPUT VOLTAGE (V)
SUPPLY CURRENT (µA)
100
LTC1262 G02
600
480
75
10.4
5.75
6.0
10.2
0
5
10 15 20 25 30 35 40 45 50
OUTPUT CURRENT (mA)
LTC1262 G03
1262 G04
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PI FU CTIO S
C1 – (Pin 1): C1 Negative Input. Connect a 0.22µF capacitor C1 between C1+ and C1 –.
C1 + (Pin 2): C1 Positive Input. Connect a 0.22µF capacitor C1 between C1+ and C1–.
C2 – (Pin 3): C2 Negative Input. Connect a 0.22µF capacitor C2 between C2 + and C2 –.
C2+ (Pin 4): C2 Positive Input. Connect a 0.22µF capacitor C2 between C2 + and C2 –.
VCC (Pin 5): Positive Supply Input Where 4.75V ≤ VCC
≤ 5.5V. Connect a 4.7µF bypass capacitor CIN to ground.
VOUT (Pin 6): 12V Output. Connect a 4.7µF bypass capacitor COUT to ground. When in the shutdown mode VOUT =
VCC.
GND (Pin 7): Ground.
SHDN (Pin 8): Logic Level Shutdown Pin. Application of a
logic low at SHDN pin will place the regulator in normal
operation. With no external connection, or with SHDN tied
to VCC, the device will be put into shutdown mode. Connect
to GND for normal operation. In shutdown mode the
charge pump is turned off and VOUT = VCC.
3
LTC1262
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BLOCK DIAGRAM
VCC
+
S3A
S3C
CIN
R1
C1+
D1 S1
SHDN
D2
S4A
C1
VOUT
+
C1 –
S3B
–
C2+
+
S4B
C2
COUT
R2
VDIV
R3
BANDGAP
REFERENCE
VBGAP
S2
C2 –
S3D
OSCILLATOR
CHARGE
PUMP
GND
LTC1262 • BD
S1 AND S2 SHOWN WITH SHDN PIN LOW.
S3A, S3B, S3C, S3D, S4A AND S4B SHOWN WITH OSCILLATOR OUTPUT LOW AND VDIV < VBGAP – VHYST.
COMPARATOR HYSTERISIS IS ±VHYST.
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TI I G DIAGRA S
t OFF
t ON
VOUT
11.4V
VOUT
VCC
VCC
1.4V
1.4V
0V
LTC1262 • F01
Figure 1. LTC1262 Timing Diagram
4
1
C1–
SHDN
2
C1+
GND
3
C2 –
8
C2
0.22µF
4
C2+
VOUT
VCC
VSHUTDOWN
7
LTC1262
5.1V
VSHDN
C1
0.22µF
6
5
+
COUT
4.7µF
+
CIN
4.7µF
VCC
4.75V TO 5V
Figure 2. LTC1262 Timing Circuit
VOUT
LTC1262 • F02
LTC1262
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APPLICATIONS INFORMATION
Operation
Choice of Capacitors
The LTC1262 uses a charge pump tripler to generate 12V
from a VCC of 5V. The charge pump operates when clocked
by a 300kHz oscillator. When the oscillator output is low,
C1 and C2 are connected between VCC and GND, charging
them to VCC. When the oscillator output goes high, C1 and
C2 are stacked in series with the bottom plate of C1 pulled
to VCC. The top plate of C2 is switched to charge COUT and
VOUT rises. VOUT is regulated to within 5% of 12V by an
oscillator pulse gating scheme. A resistor divider senses
VOUT. When the output of the divider (VDIV) is less than the
output of a bandgap (VBGAP) by the hysteresis voltage
(VHYST) of the comparator, oscillator pulses are applied to
the charge pump to raise VOUT. When VDIV is above VBGAP
by VHYST, the oscillator pulses are prevented from clocking the charge pump. VOUT drops until VDIV is below VBGAP
by VHYST again. The gates of all internal switches are
driven between VOUT and GND. An internal diode ensures
that the LTC1262 will start up under load by charging COUT
to one diode drop below VCC.
The LTC1262 is tested with the capacitors shown in
Figure 2. C1 and C2 are 0.22µF ceramic capacitors and
CIN and COUT are 4.7µF tantalum capacitors. Refer to
Table 1 if other choices are desired.
To reduce supply current the LTC1262 may be put into
shutdown mode by floating the SHDN pin or taking it to
VCC. In this mode the bandgap, comparator, oscillator and
resistor divider are switched off to reduce supply current
to typically 0.5µA. At the same time an internal switch
shorts VOUT to VCC; VOUT takes 3.3ms to reach 5.1V (see
tOFF in Figure 1). When the SHDN pin is low, the LTC1262
exits shutdown and the charge pump operates to raise
VOUT to 12V. VOUT takes 500µs to reach the lower regulation limit of 11.4V (see tON in Figure 1).
Table 1. Recommended Capacitor Types and Values
CAPACITOR
CERAMIC
TANTALUM
ALUMINUM
C1, C2
0.22µF to 1µF
Not
Recommended
Not
Recommended
COUT
2µF (Min)
4.7µF (Min)
10µF (Min)
CIN
1µF (Min)
4.7µF (Min)
10µF (Min)
C1 and C2 should be ceramic capacitors with values in the
range of 0.22µF to 1µF. Higher values provide better load
regulation. Tantalum capacitors are not recommended as
the higher ESR of these capacitors degrades performance
when the load current is above 25mA with VCC = 4.75V.
CIN and COUT can be ceramic, tantalum or electrolytic
capacitors. The ESR of COUT introduces steps in the VOUT
waveform whenever the charge pump charges COUT. This
tends to increase VOUT ripple. Ceramic or tantalum capacitors are recommended for COUT if minimum ripple is
desired. The LTC1262 does not require a 0.1µF capacitor
between VCC and VOUT for stability.
Maximum Load Current
The LTC1262 will source up to 50mA continuously without
any damage to itself. Do not short the VOUT pin to ground.
If the VOUT pin is shorted to ground, irreversible damage
to the device will result.
5
LTC1262
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TYPICAL APPLICATI
5V to 3.3V/10A Converter
C7
0.22µF
C8
0.22µF
1
C1–
2
C1+
3
C2 –
4
C2+
SHDN
U2
LTC1262
GND
VOUT
VCC
8
7
6
+
C9
1µF
5
+
Q1
TP0610
U1
LTC1148-3.3
3
C6
10µF
25V
+
10
SHUTDOWN
6
R1
510Ω
C1
3300pF
4
C2
150pF
11
PDRIVE
SHDN
8
SENSE +
ITH
7
SENSE –
CT
NDRIVE
PGND
Q4
Si9410
L2
3µH/10A
1
VIN
SGND
Q3
Si9410
Q2
VN7002
R2
100Ω
C3
1000pF
+
R4
0.01Ω
2W
R3
100Ω
14
VOUT
3.3V
10A
+
Q5
Si9410
D1
MBRS120T3
+
C5
330µF
6.3V
×2
OS-CON
12
R6
TM
22k Burst Mode DEFEAT;
USE IF REQUIRED
Burst Mode is a trademark of Linear Technology Corporation.
6
+
VIN
5V
C4
220µF
8V
×3
PANASONIC
ECGCOKB220R
LTC1262 • TA02
LTC1262
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PACKAGE DESCRIPTION
Dimensions in inches (millimeters) unless otherwise noted.
N8 Package
8-Lead PDIP (Narrow 0.300)
(LTC DWG # 05-08-1510)
0.400*
(10.160)
MAX
8
7
6
5
1
2
3
4
0.255 ± 0.015*
(6.477 ± 0.381)
0.300 – 0.325
(7.620 – 8.255)
0.065
(1.651)
TYP
0.009 – 0.015
(0.229 – 0.381)
(
+0.035
0.325 –0.015
8.255
+0.889
–0.381
0.130 ± 0.005
(3.302 ± 0.127)
0.045 – 0.065
(1.143 – 1.651)
)
0.125
(3.175) 0.020
MIN (0.508)
MIN
0.018 ± 0.003
(0.457 ± 0.076)
N8 1197
0.100 ± 0.010
(2.540 ± 0.254)
*THESE DIMENSIONS DO NOT INCLUDE MOLD FLASH OR PROTRUSIONS.
MOLD FLASH OR PROTRUSIONS SHALL NOT EXCEED 0.010 INCH (0.254mm)
S8 Package
8-Lead Plastic Small Outline (Narrow 0.150)
(LTC DWG # 05-08-1610)
0.189 – 0.197*
(4.801 – 5.004)
8
7
6
5
0.150 – 0.157**
(3.810 – 3.988)
0.228 – 0.244
(5.791 – 6.197)
1
0.010 – 0.020
× 45°
(0.254 – 0.508)
0.008 – 0.010
(0.203 – 0.254)
0.053 – 0.069
(1.346 – 1.752)
0°– 8° TYP
0.016 – 0.050
0.406 – 1.270
0.014 – 0.019
(0.355 – 0.483)
2
3
4
0.004 – 0.010
(0.101 – 0.254)
0.050
(1.270)
TYP
*DIMENSION DOES NOT INCLUDE MOLD FLASH. MOLD FLASH
SHALL NOT EXCEED 0.006" (0.152mm) PER SIDE
**DIMENSION DOES NOT INCLUDE INTERLEAD FLASH. INTERLEAD
FLASH SHALL NOT EXCEED 0.010" (0.254mm) PER SIDE
Information furnished by Linear Technology Corporation is believed to be accurate and reliable.
However, no responsibility is assumed for its use. Linear Technology Corporation makes no representation that the interconnection of its circuits as described herein will not infringe on existing patent rights.
SO8 0996
7
LTC1262
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TYPICAL APPLICATI
Output Voltage vs Output Current for
Two Paralleled Devices
Paralleling Devices
C1–
2
+
SHDN
8
0.22µF
C1
GND
0.22µF
4
1
C2 –
VOUT
C2+
C1–
VCC
SHDN
C1+
GND
+
5
10µF
12V OUTPUT
+
10µF
VCC
4.75V TO
5.5V
8
7
0.22µF
C2 –
VOUT
4
C2+
VCC
11.8
VCC = 5.5V
11.6
11.4
VCC = 4.75V
11.2
11.0
10.8
10.6
LTC1262
3
VCC = 5V
12.2
12.0
6
0.22µF
2
12.4
7
LTC1262
3
TIE TO VCC OR FLOAT
TO SHUTDOWN BOTH
DEVICES
OUTPUT VOLTAGE (V)
1
10.4
6
0
10 20 30 40 50 60 70 80 90 100
OUTPUT CURRENT (mA)
5
NOTE: KEEP DEVICES CLOSE TOGETHER OR
USE SEPARATE 4.7µF TANTALUM
CAPACITORS IF THIS IS NOT POSSBILE.
1262 TA04
SEE FIGURE AT LEFT.
LTC1262 • TA03
RELATED PARTS
PART NUMBER
DESCRIPTION
COMMENTS
LT1106*
Micropower Step-Up DC/DC Converter for PCMCIA Card Flash Memory
PCMCIA Card Power Control, 9µA ISHDN, Small SMT
Components, Requires External Inductor
LT1109-12
Micropower Low Cost DC/DC Converter Adjustable and Fixed 12V
Three-Lead Z Package, Requires External Inductor
LT1109A-12
Micropower DC/DC Converter Flash Memory VPP Generator
Adjustable and Fixed 12V
Requires External Inductor
LT1301
Micropower High Efficiency 5V/12V Step-Up DC/DC
Converter for Flash Memory
7µA ISHDN, SMT Inductor and Capacitors
LT1309
500kHz Micropower DC/DC Converter for Flash Memory
Small SMT Inductor and Capacitors, 6µA ISHDN
* See also LT1312/LT1313 PCMCIA VPP drivers/regulators, LT1314/LT1315 PCMCIA switch matrix and the LTC1470/LTC1471/LTC1472 Protected VCC
and VPP switching matrices
8
Linear Technology Corporation
1630 McCarthy Blvd., Milpitas, CA 95035-7417● (408)432-1900
FAX: (408) 434-0507● TELEX: 499-3977 ● www.linear-tech.com
LT/TP 0298 REV A 2K • PRINTED IN USA
 LINEAR TECHNOLOGY CORPORATION 1994