MIC1557BM5 MICREL [Micrel Semiconductor], MIC1557BM5 Datasheet - Page 8

• Manufacturer Part Number: MIC1557BM5
• Manufacturer: MICREL [Micrel Semiconductor]

MIC1555/1557
connected to a higher voltage, through a high-side load. A
TTL high signal applied to CS enables a 10kHz oscillator,
which quickly develops 15V at the gate of the MOSFET,
clamped by a zener diode. A resistor from the gate to ground
ensures that the FET will turn off quickly when the MIC1557
is turned off.
Package Information
MIC1555/1557
This information is believed to be accurate and reliable, however no responsibility is assumed by Micrel for its use nor for any infringement of patents or
to 10µF
100pF
other rights of third parties resulting from its use. No license is granted by implication or otherwise under any patent or patent right of Micrel Inc.
C1
+5V
4
1
2
T/T
Figure 8. Charge-Pump
GND
VS
R
T
MIC1557
1.90 (0.075) REF
0.95 (0.037) REF
1k to 1M
3.02 (0.119)
2.80 (0.110)
OUT
MICREL INC. 1849 FORTUNE DRIVE SAN JOSE, CA 95131 USA
CS
TTL High = ON
TEL
3
5
+ 1 [phone]
R
100k
0.50 (0.020)
0.35 (0.014)
E
15V
N-Channel
MOSFET
(IRF540)
FAX
© 1998 Micrel Incorporated
1.75 (0.069)
1.50 (0.059)
1.30 (0.051)
0.90 (0.035)
+ 1 [phone]
SOT-23-5 (M5)
+12V
0.15 (0.006)
0.00 (0.000)
R
L
8
Audible Voltmeter
If an additional charge or discharge source is connected to
the timing capacitor, the frequency may be shifted by turning
the source on or off. An MIC1555 oscillator, powered by the
circuit under test, may be used to drive a small loudspeaker
or piezo-electric transducer to provide a medium frequency
for an open or high impedance state at the probe. A high tone
is generated for a high level, and a lower frequency for a logic
low on the probe.
3.00 (0.118)
2.60 (0.102)
10
0
WEB
1N914
10k
http://www.micrel.com
0.01µF
C
47k
DIMENSIONS:
Figure 9. Audible Voltmeter
T
MM (INCH)
0.60 (0.024)
0.10 (0.004)
5
4
2
THR
TRG
GND
MIC1555
0.20 (0.008)
0.09 (0.004)
R
T
10k
OUT
VS
1
3
0.001µF
10k
+5V to +18V
October 1998
100
Micrel