OMO ElectronicOMO Electronic
Expand menu
Hello, Sign inMy Account
0 Cart

MIC2177-5.0YWM

P1-P3P4-P6P7-P9P10-P12P13-P13
March 2005 1 M9999-031805
MIC2177 Micrel, Inc.MIC2177 Micrel
MIC2177
2.5A Synchronous Buck Regulator
General Description
The Micrel MIC2177 is a 200kHz synchronous buck (step-
down) switching regulator designed for high-efficiency, bat-
tery-powered applications.
The MIC2177 operates from a 4.5V to 16.5V input and
features internal power MOSFETs that can supply up to 2.5A
output current. It can operate with a maximum duty cycle of
100% for use in low-dropout conditions. It also features a
shutdown mode that reduces quiescent current to less than
5µA.
The MIC2177 achieves high efficiency over a wide output
current range by switching between PWM and skip mode.
Operating mode is automatically selected according to output
conditions. Switching frequency is preset to 200kHz and can
be synchronized to an external clock signal of up to 300kHz.
The MIC2177 uses current-mode control with internal current
sensing. Current-mode control provides superior line regula-
tion and makes the regulator control loop easy to compen-
sate. The output is protected with pulse-by-pulse current
limiting and thermal shutdown. Undervoltage lockout turns
the output off when the input voltage is less than 4.5V.
The MIC2177 is packaged in a 20-lead wide power SO
package with an operating temperature range of –40°C to
+85°C.
See the MIC2178 for externally selected PWM or skip-mode
operation.
Typical Application
Features
•4.5V to 16.5V input voltage range
• Dual-mode operation for high efficiency (up to 96%)
PWM mode for > 200mA load current
Skip mode for < 200mA load current
• 100mΩ internal power MOSFETs at 12V input
• 200kHz preset switching frequency
• Low quiescent current
1.0mA in PWM mode
500µA in skip mode
< 5µA in shutdown mode
• 100% duty cycle for low dropout operation
• Current-mode control
Simplified loop compensation
Superior line regulation
• Current limit
• Thermal shutdown
• Undervoltage lockout
Applications
•High-efficiency, battery-powered supplies
• Buck (step-down) dc-to-dc converters
• Cellular telephones
• Laptop computers
• Hand-held instruments
• Battery Charger
BIASSGND
EN
COMP
PGND
FB
OUT
VIN
C2
100µF
10V
V
OUT
5V/1A
L1, 50µH
C
C
6.8nF
C3
R1
0.01µF
10k
MIC
2177-5.0
AUTO
SYNC
R1
10k
V
IN
5.4V to 18V
C1
22µF
35V
U1
20
18
11
13 14–17 19
12
4–7
3,8
1,2,9
D1
MBRS130L
SW
10
ENABLE
SHUTDOWN
2.2
nF
70
75
80
85
90
95
100
10 100 1000 2500
EFFICIENCY (%)
OUTPUT CURRENT (mA)
5V Output
Efficiency
V
IN
= 6V
SKIP
PWM
Micrel, Inc. • 2180 Fortune Drive • San Jose, CA 95131 • USA • tel + 1 (408) 944-0800 • fax + 1 (408) 474-1000 • http://www.micrel.com
MIC2177 Micrel, Inc.
M9999-031805 2 March 2005
Ordering Information
Part Output Switching Temperature
Number Voltage Frequency Range Package Lead Finish
MIC2177-3.3BWM* 3.3V 200kHz –40°C to +85°C 20-lead WSOP Standard
MIC2177-5.0BWM* 5.0V 200kHz –40°C to +85°C 20-lead WSOP Standard
MIC2177BWM* adj. 200kHz –40°C to +85°C 20-lead WSOP Standard
MIC2177-3.3YWM 3.3V 200kHz –40°C to +85°C 20-lead WSOP Pb-Free
MIC2177-5.0YWM 5.0V 200kHz –40°C to +85°C 20-lead WSOP Pb-Free
MIC2177YWM adj. 200kHz –40°C to +85°C 20-lead WSOP Pb-Free
Pin Description
Pin Number Pin Name Pin Function
1, 2, 9 VIN Supply Input: Controller and switch supply. Unregulated supply input to
internal regulator, output switches, and control circuitry. Requires bypass
capacitor to PGND. All three pins must be connected to V
IN
.
3,8 SW Switch (Output): Internal power MOSFET switch output. Both pins must be
externally connected together.
4,5,6,7 PGND Power Ground: Output stage ground connections. Connect all pins to a
common ground plane.
10 OUT Output Voltage Sense (Input): Senses output voltage to determine minimum
switch current for PWM operation. Connect directly to V
OUT
.
11 AUTO Automatic Mode: Connect 2.2nF timing capacitor for automatic PWM-/skip-
mode switching. Regulator operates exclusively in PWM mode when pin is
pulled low.
12 FB Feedback (Input): Error amplifier inverting input. For adjustable output
version, connect FB to external resistive divider to set output voltage. For
3.3V and 5V fixed output versions, connect FB directly to output.
13 COMP Compensation: Internal error amplifier output. Connect to capacitor or series
RC network to compensate the regulator control loop.
14,15,16,17 SGND Signal Ground: Ground connection of control section. Connect all pins to
common ground plane.
18 SYNC Frequency Synchronization (Input): Optional clock input. Connect to
external clock signal to synchronize oscillator. Leading edge of signal above
1.7V terminates switching cycle. Connect to SGND if not used.
19 BIAS Bias Supply: Internal 3.3V bias supply output. Decouple with 0.01µF
bypass capacitor and 10kΩ to SGND. Do not apply any external load.
20 EN Enable (Input): Logic high enables operation. Logic low shuts down
regulator. Do not allow pin to float.
Pin Configuration
2VIN
3SW
4PGND
5PGND
6PGND
7PGND
1VIN
8SW
9
VIN
EN20
BIAS19
SYNC18
SGND17
SGND16
SGND15
10
OUT
14
13
12
11
AUTO
FB
COMP
SGND
20-Lead Wide SOP
* Standard product will be supported as Pb-Free IAW PPCN #040004 effective 1-1-2005 pending residual depletion.,
March 2005 3 M9999-031805
MIC2177 Micrel, Inc.
Absolute Maximum Ratings
Supply Voltage [100ms transient] (V
IN
) ......................... 18V
Output Switch Voltage (V
SW
) ........................................ 18V
Output Switch Current (I
SW
) ......................................... 6.0A
Enable, Output-Sense Voltage (V
EN
, V
OUT
) ................. 18V
Sync Voltage (V
SYNC
) ..................................................... 6V
Operating Ratings
Supply Voltage (V
IN
) ..................................... 4.5V to 16.5V
Junction Temperature Range (T
J
) ........... –40°C to +125°C
Electrical Characteristics
V
IN
= 7.0V; T
A
= 25°C, bold indicates –40°C ≤ T
A
≤ 85°C; unless noted.
Symbol Parameter Condition Min Typ Max Units
I
SS
Input Supply Current PWM mode, output not switching, 1.0 1.5 mA
4.5V ≤ V
IN
≤ 16.5V
skip mode, output not switching, 500 650 µA
4.5V ≤ V
IN
≤ 16.5V
V
EN
= 0V, 4.5V ≤ V
IN
≤ 16.5V 1 25 µA
V
BIAS
Bias Regulator Output Voltage V
IN
= 16.5V 3.10 3.30 3.4 V
V
FB
Feedback Voltage MIC2177 [adj.]: V
OUT
= 3.3V, I
LOAD
= 0 1.22 1.245 1.27 V
V
OUT
Output Voltage MIC2177 [adj.]: V
OUT
= 3.3V, 3.20 3.3 3.40 V
5V ≤ V
IN
≤ 16V, 10mA ≤ I
LOAD
≤ 2A 3.14 3.46 V
MIC2177-5.0: I
LOAD
= 0 4.85 5.0 5.15 V
MIC2177-5.0: 4.85 5.0 5.15
6V ≤ V
IN
≤ 16V, 10mA ≤ I
LOAD
≤ 2A 4.75 5.25 V
MIC2177-3.3: I
LOAD
= 0 3.20 3.3 3.40 V
MIC2177-3.3: 3.20 3.3 3.40 V
5V ≤ V
IN
≤ 16V, 10mA ≤ I
LOAD
≤ 2A 3.14 3.46 V
V
TH
Undervoltage Lockout upper threshold 4.25 4.35 V
V
TL
lower threshold 3.9 4.15 V
I
FB
Feedback Bias Current MIC2177 [adj.] 60 150 nA
MIC2177-5.0, MIC2177-3.3 20 40 µA
A
VOL
Error Amplifier Gain 0.6V ≤ V
COMP
≤ 0.8V 15 18 20
Error Amplifier Output Swing upper limit 0.9 1.5 V
lower limit 0.05 0.1 V
Error Amplifier Output Current source and sink 15 25 35 µA
f
O
Oscillator Frequency 160 200 240 kHz
D
MAX
Maximum Duty Cycle V
FB
= 1.0V 100 %
t
ON min
Minimum On-Time V
FB
= 1.5V 300 400 ns
SYNC Frequency Range 220 300 kHz
SYNC Threshold 0.8 1.6 2.2 V
SYNC Minimum Pulse Width 500 ns
I
SYNC
SYNC Leakage V
SYNC
= 0V to 5.5V –1 0.01 1 µA
I
LIM
Current Limit PWM mode, V
IN
= 12V 3.8 4.7 5.7 A
skip mode 600 mA
R
ON
Switch On-Resistance high-side switch, V
IN
= 12V 90 250 mΩ
low-side switch, V
IN
= 12V 110 250 mΩ
I
SW
Output Switch Leakage V
SW
= 16.5V 1 10 µA
P1-P3P4-P6P7-P9P10-P12P13-P13

MIC2177-5.0YWM

Mfr. #:
Buy MIC2177-5.0YWM
Manufacturer:
Microchip Technology / Micrel
Description:
Switching Voltage Regulators 2.5A 200kHz Synchronous Switcher
Lifecycle:
New from this manufacturer.
Delivery:
DHL FedEx Ups TNT EMS
Payment:
T/T Paypal Visa MoneyGram Western Union

Products related to this Datasheet