MCP1256/7/8/9
Regulated 3.3V, Low-Ripple Charge Pump with Low-
Operating Current SLEEP Mode or BYPASS Mode
Features
• Inductorless 1.5x, 2x Boost DC/DC Converter
• Output Voltage: 3.3V
• High Output Voltage Accuracy:
- ±3.0% (V
OUT
Fixed)
• Output Current Up To 100 mA
• 20 mV
PP
Output Voltage Ripple
• Thermal Shutdown and Short Circuit Protection
• Uses Small Ceramic Capacitors
• Switching Frequency: 650 kHz
• Low-Power SLEEP Mode: MCP1256/7
• BYPASS Mode: MCP1258/9
• Low-Power Shutdown Mode: 0.1
μA
(Typical)
• Shutdown Input Compatible with 1.8V Logic
• V
IN
Range: 1.8V to 3.6V
• Soft-Start Circuitry to Minimize Inrush Current
• Temperature Range: -40°C to +125°C
• Packaging:
- 10-Pin, 3 mm x 3 mm DFN
- 10-Pin, MSOP
Description
The MCP1256, MCP1257, MCP1258 and MCP1259
are inductorless, positive regulated charge pump
DC/DC converters. The devices generate a regulated
3.3V output voltage from a 1.8V to 3.6V input. The
devices are specifically designed for applications
operating from 2-cell alkaline, Ni-Cd, or Ni-MH
batteries or by one primary lithium MnO2 (or similar)
coin cell battery.
The MCP1256, MCP1257, MCP1258 and MCP1259
provide high efficiency by automatically switching
between 1.5x and 2x boost operation. In addition, at
light output loads, the MCP1256 and MCP1257 can be
placed in a SLEEP mode, lowering the quiescent
current while maintaining the regulated output voltage.
Alternatively, the MCP1258 and MCP1259 provide a
BYPASS feature connecting the input voltage to the
output.
This
allows
for
real-time
clocks,
microcontrollers or other system devices to remain
biased with virtually no current being consumed by the
MCP1258 or MPC1259.
In normal operation, the output voltage ripple is below
20 mV
PP
at load currents up to 100 mA. Normal opera-
tion occurs at a fixed switching frequency of 650 kHz,
avoiding interference with sensitive IF bands.
The MCP1256 and MCP1258 feature a power-good
output that can be used to detect out-of-regulation
conditions. The MCP1257 and MCP1259 feature a low-
battery indication that issues a warning if the input
voltage drops below a preset voltage threshold.
Extremely low supply current and few external parts (4
capacitors) make these devices ideal for small, battery-
powered applications. A Shutdown mode is also
provided for further power reduction.
The devices incorporate thermal and short-circuit pro-
tection. Two package offerings are provided: 10-pin
MSOP and 10-lead 3 mm x 3 mm DFN. The devices
are completely characterized over the junction temper-
ature range of -40°C to +125°C.
Applications
•
•
•
•
Pagers
Portable Measurement Instruments
Home Automation Products
PICmicro
®
MCU Bias
Typical Application
INPUT
1.8V to 3.6V
C
IN
10
μF
MCP1256
7 V
IN
V
OUT
5
R
1
OUTPUT
3.3V
C
OUT
10
μF
Power-Good
Indication
10 SHDN
1
PGOOD
C
1
1
μF
4 C +
1
8 C -
1
C
2
+
C
2
-
6
3
C
2
1
μF
ON / OFF
2 SLEEP
GND
9
Typical Application with Power-Good Indication
©
2006 Microchip Technology Inc.
DS21989A-page 1
MCP1256/7/8/9
1.0
ELECTRICAL
CHARACTERISTICS
† Notice:
Stresses above those listed under “Maximum
Ratings” may cause permanent damage to the device. This is
a stress rating only and functional operation of the device at
those or any other conditions above those indicated in the
operational listings of this specification is not implied.
Exposure to maximum rating conditions for extended periods
may affect device reliability.
Absolute Maximum Ratings†
Power Supply Voltage, V
IN
...............................................3.8V
Voltage on Any Pin w.r.t. GND ................. -0.3V to (V
IN
+0.3V)
Output Short Circuit Duration ................................continuous
Storage Temperature Range .........................-65°C to +150°C
Ambient Temperature with Power Applied ....-55°C to +125°C
Maximum Junction Temperature ................................. +150°C
ESD protection on all pins
Human Body Model (1.5 kΩ in Series with 100 pF).......≥ 2 kV
Machine Model (200 pF, No Series Resistance) .............200V
DC CHARACTERISTICS
Electrical Specifications:
Unless otherwise indicated, all limits apply for V
IN
= 1.8V to 3.6V, SHDN = V
IN
, C
IN
= C
OUT
= 10
μF,
C
1
= C
2
= 1
μF,
I
OUT
= 10 mA, T
J
= -40°C to +125°C. Typical values are at T
J
= +25°C.
Parameters
ALL DEVICES
Supply Voltage
Output Voltage
Output Voltage Accuracy
Output Current
V
IN
V
OUT
V
OUT
I
OUT(MAX)
1.8
—
-3.0
30
70
100
Short Circuit Current
Power Efficiency
I
SC
η
—
—
—
—
—
—
—
—
—
—
—
—
—
—
Shutdown Input - SHDN
SHDN Input Voltage Low
SHDN Input Voltage High
SHDN Input Leakage
Current
SHDN Quiescent Current
Thermal Shutdown
Thermal Shutdown
Threshold
Thermal Shutdown
Hysteresis
T
J
T
J(HYS)
—
—
160
15
—
—
°C
°C
V
IL(SHDN)
V
IH(SHDN)
I
LK(SHDN)
I
Q
—
1.4
—
—
—
—
0.001
0.25
0.4
—
0.1
2
V
V
μA
μA
V
SHDN
= 0V, T
J
= +25°C
—
3.3
±0.5
—
—
—
150
84.5
84.5
76.4
80.1
64.0
67.1
67.5
69.7
76.0
76.7
65.0
71.0
71.6
3.6
—
+3.0
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
V
V
%
mA
mA
mA
mA
%
%
%
%
%
%
%
%
%
%
%
%
%
I
OUT
= 10 mA to I
OUT(MAX)
1.8V < V
IN
< 2.0V
2.0V < V
IN
< 2.2V
2.2V < V
IN
< 3.6V
V
OUT
= 0V, V
IN
= 1.8V to 3.6V
V
IN
= 1.8V, I
OUT
= 10 mA
V
IN
= 1.8V, I
OUT
= 50 mA
V
IN
= 2.0V, I
OUT
= 10 mA
V
IN
= 2.0V, I
OUT
= 50 mA
V
IN
= 2.4V, I
OUT
= 10 mA
V
IN
= 2.4V, I
OUT
= 50 mA
V
IN
= 2.4V, I
OUT
= 100 mA
V
IN
= 2.8V, I
OUT
= 10 mA
V
IN
= 2.8V, I
OUT
= 50 mA
V
IN
= 2.8V, I
OUT
= 100 mA
V
IN
= 3.0V, I
OUT
= 10 mA
V
IN
= 3.0V, I
OUT
= 50 mA
V
IN
= 3.0V, I
OUT
= 100 mA
Sym
Min
Typ
Max
Unit
s
Conditions
©
2006 Microchip Technology Inc.
DS21989A-page 3
MCP1256/7/8/9
AC CHARACTERISTICS
Electrical Specifications:
Unless otherwise indicated, all limits apply for V
IN
= 1.8V to 3.6V, SHDN = V
IN
, C
IN
= C
OUT
= 10
μF,
C
1
= C
2
= 1
μF,
I
OUT
= 10 mA, T
J
= -40°C to +125°C. Typical values are at T
J
= +25°C.
Parameters
ALL DEVICES
Internal Oscillator Frequency
Output Voltage Ripple,
Normal Operation
F
OSC
V
RIP
—
—
—
—
—
V
OUT
Wake-up Time From
Shutdown
T
WKUP
—
650
5
20
12
55
175
—
—
—
—
—
—
kHz
mVp-p
mVp-p
mVp-p
mVp-p
μs
C
OUT
= 10
μF,
I
OUT
= 10 mA
C
OUT
= 10
μF,
I
OUT
= 100 mA
C
OUT
= 2.2
μF,
I
OUT
= 10 mA
C
OUT
= 2.2
μF,
I
OUT
= 100 mA
V
IN
= 3.0V, I
OUT
= 10 mA,
SHDN = V
IH(MIN)
,
V
OUT
from 0 to 90% Nominal Regulated
Output Voltage
C
OUT
= 10
μF,
I
OUT
= 0.1 mA
C
OUT
= 10
μF,
I
OUT
= 4 mA
C
OUT
= 2.2
μF,
I
OUT
= 0.1 mA
C
OUT
= 2.2
μF,
I
OUT
= 4 mA
V
IN
= 3.0V, I
OUT
= 10 mA,
SHDN = V
IH(MIN)
,
V
OUT
from 0 to 90% Nominal Regulated
Output Voltage
Sym
Min
Typ
Max
Units
Conditions
MCP1256 and MCP1257
Output Voltage Ripple,
SLEEP Mode
V
RIP
—
—
—
—
MCP1258 and MCP1259
V
OUT
Wake-up Time From
BYPASS
T
WKUP
—
150
—
μs
40
60
40
60
—
—
—
—
mVp-p
mVp-p
mVp-p
mVp-p
TEMPERATURE SPECIFICATIONS
Electrical Specifications:
Unless otherwise indicated, all limits apply for V
IN
= 1.8V to 3.6V, SHDN = V
IN
, C
IN
= C
OUT
= 10
μF,
C
1
= C
2
= 1
μF,
I
OUT
= 10 mA, T
J
= -40°C to +125°C. Typical values are at T
J
= +25°C.
Parameters
Temperature Ranges
Specified Temperature Range
Operating Temperature Range
Storage Temperature Range
Thermal Package Resistances
Thermal Resistance, 10-Lead, MSOP
Thermal Resistance, 10-Lead, DFN
3 mm x 3 mm
θ
JA
θ
JA
—
—
200
57
—
—
°C/W
°C/W
4-Layer JC51-7 Standard Board,
Natural Convection
4-Layer JC51-7 Standard Board,
Natural Convection
T
J
T
J
T
A
-40
-40
-65
—
—
—
+125
+125
+150
°C
°C
°C
Sym
Min
Typ
Max
Units
Conditions
©
2006 Microchip Technology Inc.
DS21989A-page 5
51mcu
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